federal register - United States Department of Labor · Mine Ventilation; Final Rule. 9764 Federal Register/Vol. 61, No. 48/Monday, March 11, 1996/Rules and Regulations DEPARTMENT

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Part III

Department of LaborMine Safety and Health Administration

30 CFR Part 75Safety Standards for Underground CoalMine Ventilation; Final Rule

9764 Federal Register / Vol. 61, No. 48 / Monday, March 11, 1996 / Rules and Regulations

DEPARTMENT OF LABOR

Mine Safety and Health Administration

30 CFR Part 75

RIN 1219–AA11

Safety Standards for UndergroundCoal Mine Ventilation

AGENCY: Mine Safety and HealthAdministration, (MSHA) Labor.ACTION: Final rule.

SUMMARY: This final rule revises theMine Safety and HealthAdministration’s (MSHA’s) existingsafety standards for ventilation ofunderground coal mines. Afterpublication of the existing standards,the U.S. Court of Appeals in the D.C.Circuit stayed the application of onestandard and MSHA stayed twostandards. The rule revises these stayedprovisions, revises or clarifies otherprovisions in the rule and includessome new provisions. The provisions ofthe final rule are expected to decreasethe potential for fatalities, particularlyaccidents which can result in multipledeaths, and to reduce the risk of injuriesand illnesses in underground coalmines. For the convenience of thereader, MSHA has published the fulltext of the ventilation standards forunderground coal mines in thisdocument.EFFECTIVE DATE: The final rule iseffective June 10, 1996.FOR FURTHER INFORMATION CONTACT:Patricia W. Silvey, Director, Office ofStandards, Regulations and Variances,MSHA, phone 703/ 235–1910; fax 703/235–5551.

SUPPLEMENTARY INFORMATION:

I. Background

The mining of coal underground hashistorically been recognized as one ofthe more hazardous occupations in theworld. It is a universally recognizedprinciple of underground coal minesafety that there must be properventilation of the mine. Indeed, noaspect of safety in underground coalmining is more fundamental thanproper ventilation. A basic tenet ofmining safety states that ventilationmust be sufficient: (1) To dilute, renderharmless and carry away the hazardouscomponents of mine air, such aspotentially explosive methane; and (2)to provide necessary levels of oxygen tothe miners’ working environment.Ventilation safety programs aredesigned around this philosophy. Thehistory of mining is replete with tragicincidents where one aspect or another of

a necessary ventilation safety protectionwas either not in place or not followed,with disastrous results. Examplesinclude the explosion at the Monogahmine in 1907 in which 362 minersperished, the worst mining disaster inthe history of the United States. Othermore recent examples include theFarmington disaster in 1968 in which 78miners died, the Scotia mine in 1976where 26 died, Grundy No. 17 in 1981where 13 died, Wilberg in 1984 where27 died, Pyro in 1989 with 10 deathsand Southmountain in 1992 where 8miners died. In 1969 and again in 1977,Congress recognized the hazards ofimproper ventilation and established arole for the government in addressingventilation hazards. MSHA, with thecooperation of labor and industry, hasmet with a large measure of success inreducing the accidents, injuries andfatalities that have resulted from poorventilation practices. For example,explosions and fires in a 29 year periodfrom 1940 to 1968 resulted in the deathsof 491 miners. Since the passage of theFederal Coal Mine Health and SafetyAct of 1969, 178 explosion and firerelated deaths have occurred. WhileMSHA recognizes that this number isstill unacceptable, the significantreduction in loss of life cannot beignored. To a great extent, theframework for this success has been theimplementation of effective ventilationstandards.

Preventing recurrence of disasters likethose of the past remains the toppriority of MSHA. MSHA believes thata serious commitment by management,labor, and government is necessary todevelop effective, yet reasonable andpractical regulations that protect thesafety and health of our nation’s miners.MSHA anticipates that this rulemaking,which revises portions of thecomprehensive ventilation rulepublished in 1992 (57 FR 20868, May15, 1992) and adds new provisions, willbring the coal mining industry closer tothat objective.

The comprehensive 1992 ventilationrulemaking was closely followed byinterested industry and labor groups,who frequently expressed divergentviews on approaches to resolvingventilation issues. Certain commentersexercised their right to challenge therule and the U.S. Court of Appeals forthe D.C. Circuit Court stayed oneprovision relating to oxygen and carbondioxide in the bleeder entries. MSHAheld a series of informational meetingsaround the country during which itexplained the application of the rule. Inso doing, MSHA listened to manyquestions about the implementation ofthe rule. MSHA was sensitive to the

views expressed at these meetings andgave serious consideration to theseissues. Some of these comments becamethe basis for portions of this rulemaking.Internal discussions of MSHA’sexperience with the implementation ofthe rule led MSHA to include still otherissues in this rulemaking. In fact, MSHAstayed the application of two additionalprovisions in response to potentialproblems pointed out by interestedparties. These stayed provisions relateto actions following the stoppage of themain mine fan with personsunderground and to a potential firehazard from the enclosure ofcompressors in a noncombustiblestructure. MSHA addresses these issuesin the rulemaking. Once MSHA decidedthat it was going to proceed with arulemaking to address these issues, itadded other provisions to the package toallow all parties an opportunity tocomment where they expressed theview that they had insufficientopportunity to comment on the existingrule (The comprehensive rule that waspublished in the Federal Register onMay 15, 1992). The rule MSHAproposed also included issues raised byparties in litigation challenging theexisting rule. MSHA anticipates that thefinal rule should resolve mattersincluded in the challenge raised by thelitigation of the existing rule. Finally, inan effort to address confusion thatseemed to exist with certain provisionsof the existing ventilation rulepromulgated in May of 1992, MSHAeither proposed clarifications to theexisting rule or discussed the affectedprovisions in the preambles to theproposed and final rules in an effort toclarify them.

The issues in the rulemaking arecomplex and highly technical.Comments to the proposal (publishedon May 19, 1994, 59 FR 26536) andcomments following the public hearings(held in September and October 1994, inPrice, Utah, Logan, West Virginia, andWashington, Pennsylvania) wereextensive. One party alone submittedover two thousand pages of writtencomments and over 275 exhibits. Notonly were the safety issues involvedcomplex, but in many cases, MSHA’stask was made more difficult by hearingdiametrically opposed viewpoints.

Major Improvements in the Final RuleThe final rule provides a number of

significant improvements to the existingventilation regulations. For example, thefinal rule provides for the electronicstorage of records. A major portion ofthe mining industry has this capabilityat the present time through computertechnology at the mine site. Electronic

9765Federal Register / Vol. 61, No. 48 / Monday, March 11, 1996 / Rules and Regulations

record retention can reduce the cost ofstorage and maintenance of records andprovide for ease in access and transferof information without reducing theprotection afforded miners.Additionally, having recordselectronically stored can facilitate trendanalysis, allowing for earlier detectionand correction of potential hazards.

The final rule also requires pressurerecorders or an option of the use of a fanmonitoring system on main mine fans atall mines. This represents a major steptoward monitoring the mine fanscontrolling the ventilation at the minesand helps assure that the miners haveuncontaminated air at all times. Thefinal rule also provides for methanetesting at the face during miningoperations. This technology isespecially useful for taking methanetests during extended cut miningoperations. The methane testingevaluates air flow to the face todetermine that methane is sufficientlydiluted, rendered harmless, and carriedaway so as to reduce or eliminate thehazards associated with methaneliberated during mining operations.

Other improvements in the ruleinclude revisions to the three stayedprovisions in the existing rule. Airquality levels for oxygen and carbondioxide in bleeders are established toprotect mine examiners who arerequired to travel to determine if thebleeders are functioning properly. Asecond stayed provision is revised tolimit the use of transportationequipment during the withdrawal ofminers after an unintentional fanstoppage. This revision to the existingrule reduces the likelihood of anignition from methane that canaccumulate during the fan stoppage.The third stayed provision is revised toallow the option of attending rather thanhousing compressors in anoncombustible enclosure. The hazardsassociated with the operation ofcompressors in underground mineswere demonstrated at the Wilberg minedisaster, where 27 people lost their livesas a result of a compressor fire.

This final rule provides for an alertand alarm device to be located outsideof noncombustible structures housingelectrical installations. The alert andalarm assures that miners are madeaware of a problem in time to extinguisha fire or safely evacuate an area or themine as necessary for safety. Anotherchange to the existing rule involvesminers or their representatives in themine ventilation plan approval processbefore the plan is submitted forapproval. This provides for theopportunity for input from those havingfirst hand knowledge in the particular

mining conditions and practices thatimpact the plan approval.

Other safety enhancements from theexisting rule include: requiring the useof extendable probes to conductmethane tests at deep cuts; requiring on-shift examinations on other than coalproducing shifts; and accepting aperformance test to determine minimumdimensions at certain locations inescapeways.

Finally, the final rule clarifies existingregulations that were considered vagueby some parties or were misunderstood.For example, the final rule provides thatcertified pumpers can conduct theirown examination rather than requiringthe examination to be conducted duringthe preshift segment of the miningoperation.

To serve the interests of the miningcommunity, MSHA has republished thefull text of subpart D of 30 CFR part 75as it will read upon promulgation of thisrule.

II. Discussion of the Final Rule

A. General Discussion

In developing the final rule, MSHAhas made every effort to address thecomments received during therulemaking, and to develop practicalrequirements for real safety problems.Both the costs and the benefits of eachstandard were also considered. Inaddition, each standard, as well asrevisions and deletions, was carefullyconsidered against the statutoryrequirement that nothing in the finalrule shall reduce the protection affordedminers by an existing mandatory healthor safety standard. Where appropriate,MSHA has provided for a phase inperiod to allow mine operators time toeffectively plan and implement thenecessary changes.

MSHA carefully analyzed thecomments received and responded inmany instances by revising theproposed requirements. For example,unlike the proposal, the final rule doesnot require the second levelcountersigning of records; allows theuse of nonpermissible equipment whenconducting an examination upon restartof a fan following unintentional fanstoppages, and requires pressurerecording devices or an option of theuse of a fan monitoring system to beused on all main mine fans.

Several commenters strongly urgedMSHA to proceed in this rulemaking onthe issue of using air coursed throughthe belt entries (‘‘belt air’’) to ventilatethe working face. MSHA has completedits consideration of the Report of theSecretary’s Advisory Committee Reporton Belt Air and has placed the issue of

using belt air to ventilate the workingface on the rulemaking agenda fordevelopment of a proposed rule. Thus,‘‘belt air’’ is not addressed in thisrulemaking.

MSHA has also received commentsand recommendations on a number ofother issues that are outside the scopeof this rulemaking. For example, muchof the extensive testimony directedtoward the use of atmosphericmonitoring systems was beyond theissues dealt with in this rulemaking.Also, recommendations for the use oftransparent or translucent material forcheck curtains exceed the scope of thisrulemaking. The final rule, therefore,does not include theserecommendations.

Commenters to the proposalfrequently included a discussion ofvarious accident reports, most writtenby MSHA. In addition, there werediscussions of other documents relatedto specific incidents or mines, such asMSHA Internal Review Reports orspecific mine plans. In some cases, thedocuments were submitted for inclusionin the record. In other cases, thedocuments were merely referenced.

MSHA is independently aware of theextensive history of ventilation relatedexplosions, and has considered thisinformation. Where appropriate, thisinformation is discussed in the section-by-section analysis in the preamble ofthis rule. MSHA is aware that accidentscan result from or be contributed to bythe violation of one or more of theexisting standards. In that context,MSHA has found that the solution is notnecessarily to promulgate anotherstandard. (The offender may be as likelyto ignore it as well.) Instead, fordemonstrated noncompliance withexisting standards, the solution is oftenfound in increased emphasis, training,or enforcement, rather than in thepromulgation of additional rules.

Several sections of the final rule dealwith requirements for sections and areaswhere mechanized mining equipment isbeing installed or removed. Theseprovisions, which were included in theexisting standard published in May1992, were reproposed without changefor the purpose of receiving additionalcomments from all interested parties.One commenter cited the WilliamStation mine explosion as evidence ofthe need for these requirements. Othercommenters reiterated an earlierobjection that the standards wereprocedurally flawed. MSHA does notagree that these provisions areprocedurally flawed and notes that eachof these standards was reproposed andnot simply restated as part of thisrulemaking. Comments relative to the


technical merits of an individualstandard are addressed in the section-by-section portion of this preamble.

Recordkeeping Requirements in theFinal Rule

The final rule revises therecordkeeping requirements for severalstandards. The standards affected are§ 75.310, Installation of main mine fans;§ 75.312, Main mine fan examinationsand records; § 75.342, Methanemonitors; § 75.360, Preshiftexamination; § 75.362, On-shiftexamination; § 75.363, Hazardousconditions; posting, correcting andrecording; § 75.364, Weeklyexaminations; and § 75.370, Mineventilation plan; contents.

Generally, the final rule requiresexaminers to record the results ofmethane tests as a percent of methanedetected; records must be made in abook that is secure and not susceptibleto alteration, or electronically in such amanner as to be secure and notsusceptible to alteration; and recordsmust be countersigned by the mineforeman by the end of the mineforeman’s next regularly scheduledworking shift. These rules are intendedto assure that examination results aremaintained and made available, andthat the appropriate level of minemanagement is made aware ofconditions or problems requiringattention. The revisions also help assurethe integrity of records and enable minemanagement to review the quality of theexaminations. MSHA intends the term‘‘secure and not susceptible toalteration’’ when applied to electronicstorage to mean that the stored recordcannot be modified. One example ofacceptable storage would be a ‘‘writeonce, read many’’ drive.

Numerous comments were receivedboth supporting and opposing theproposed recordkeeping requirements.MSHA reviewed and fully consideredeach of these comments. The proposalwould have required that records bekept in either state-approved books or inbound books with sequential machine-numbered pages. Commenters arguedthat under the existing rule records maybe falsified or altered. Commenters alsostated that accident investigations havedemonstrated the need for improvedrecords. Other commenters asserted thatthe proposed requirement for boundbooks with sequential machine-numbered pages adds an economicburden for the majority of compliantoperators and another way should befound, ‘‘to foil the very few who arerecalcitrant.’’ Other commenters statedthat since all records currently include

dates and times, machine-numberedpages are unnecessary.

Some record books that are currentlyin use and acceptable under the existingstandards are vulnerable to misuse ormanipulation. For example, under theexisting rule, records could be kept ina spiral notebook or even a loose leafbinder. The final rule addresses thisissue by requiring that records be madein books that are secure and notsusceptible to alteration. Examples ofbooks that are considered by MSHA tobe secure and not susceptible toalteration include, but are not limitedto, record books that are currentlyapproved by state mine safety agencies,and permanently bound books.Examples of books that would not beconsidered books that are secure andnot susceptible to alteration includeloose leaf binders and spiral note books.

Several commenters advocated theuse of computers for the storage andretrieval of records. In support of thisapproach, the commenters citedcomputer records as being highlyaccurate, requiring less storage spaceand facilitating data retrieval. Othercommenters expressed concern for thesecurity of records stored electronically,and offered examples of breaches ofsecurity in record systems at banks andnational security installations asevidence to support this concern.

Electronic storage of information andassessing it through computers is moreand more a common business practicegenerally and in the mining industry.Recognizing this trend, the final rulepermits the use of electronically storedrecords provided they are secure andnot susceptible to alteration, are able tocapture the information and signaturesrequired, and are accessible to therepresentative of the miners and therepresentatives of the Secretary. Basedon the rulemaking record, MSHAbelieves that electronic records meetingthese criteria are practical and asreliable as traditional records.

In the preamble to the proposal,MSHA expressed its intent to require ahard copy printout of the informationstored electronically to be availablewithin 1 hour of a request, and torequire backing up of the informationwithin 24 hours. Commenters objectedto making the records available within1 hour as being too stringent andunnecessarily requiring a person to beon duty at all times. MSHA agrees thatthe requirement would be overlyburdensome and has not included it inthe final rule. Similarly, MSHA has notincluded a specific requirement forbacking up the computer data. The finalrule requires that the records be secure.This encompasses backing up the data

as appropriate to the conditions andelectronic storage system used at themine. Upon reconsideration, MSHA hasconcluded that an additional specificrequirement would be an unnecessaryburden and has not included it in therule.

A variety of comments were receivedregarding the countersigning of certainrecords by the mine foreman, and thetime frame permitted for countersigning.The final rule adopts the proposal thatthe mine foreman must countersign therecord by the end of the mine foreman’snext regularly scheduled working shift.The mine foreman is the person mostresponsible for the day-to-day operationof the mine. It is essential for the healthand safety of the miners that the mineforeman be fully aware of theinformation contained in examinationreports so as to be able to allocateresources to correct safety problems asthey develop. Allowing until the end ofthe mine foreman’s next regularlyscheduled working shift to countersignthe reports assures that the mineforeman is aware of the results of theexamination in sufficient time to initiatecorrective actions. In response tocommenters, the final rule allows amine official equivalent to a mineforeman to countersign the records.

Some commenters suggested that thetime for countersigning is unnecessarilylong, and that the final rule shouldrestore a previous requirement thatcountersigning be completed‘‘promptly.’’ The term ‘‘promptly’’involves a level of ambiguity that iseliminated by specifying the time forcountersigning records. The record doesnot show that the time set by the finalrule would expose miners to safety orhealth risks. Also, hazardous conditionsare required to be correctedimmediately.

Commenters suggested that the term‘‘mine foreman’’ be replaced by a‘‘certified person responsible forventilation of the mine or his designee.’’Another commenter suggested that therecord could be countersigned by themine foreman or any other mine officialresponsible for the day-to-day operationof the mine. Commenters stated thatsome operations no longer use the terms‘‘mine foreman’’, ‘‘mine manager,’’ or‘‘superintendent.’’ To provide foralternative management titles, the finalrule incorporates the phrase ‘‘orequivalent mine official.’’

Numerous comments were receivedregarding the requirement of theproposal for second level countersigningby the mine superintendent, minemanager, or other mine official to whomthe mine foreman is directlyaccountable within 2 scheduled


production days thereafter. Commentersobjecting to the proposal stated thathigher level management should be ableto delegate responsibility, noting thatoften this level of official has more thanone mine to oversee and may notnecessarily be available within theproposed two days. One commentersuggested allowing three days forsecond level countersigning in order torecognize that such an official often hasnumerous obligations and to allow fornormal absences. Other commenterssimply recommended that the secondlevel countersigning be deleted.

Another commenter stated that somestates hold the mine foreman legallyresponsible, that the mine foremanshould correct hazardous conditionsimmediately and withdraw miners asappropriate, and that the second levelcountersigning would add no measureof safety. One commenter noted that inmany cases the mine manager orsuperintendent is not a certifiedindividual and long periods may elapseduring which this person does not gounderground. In these instances, theperson countersigning would have littleor no understanding or first handknowledge of the conditions in themine. Commenters stated thatcountersigning by the mine foreman isadequate notification to the operator ofany deficiency and that the mineforeman has the necessary resources andresponsibility to correct any situationnoted in the records.

Other commenters supported theproposal noting that second levelcountersigning would provide anadditional level of accountability. Thesecommenters also suggested that in theevent of a major accident, the secondlevel countersigning requirement wouldbe important in fully assessing thecontributing causes.

MSHA has determined thatcountersigning by the mine foreman orequivalent mine official, as specified inthe final rule, provides the meansnecessary to detect and correctdeveloping hazards in a mine.Countersigning by the mine foremanassures the necessary notification to anofficial with the knowledge of the day-to-day operation of the mine having theauthority to maintain the mine in a safeoperating condition. Agency experiencehas demonstrated that higher level mineofficials commonly lack hands-oninvolvement or in-depth knowledge ofthe specific conditions underground orhow the highly detailed ventilationrules impact upon those conditions.Therefore, countersigning by a mineofficial at a higher level does not assureany additional level of safety andimposes an unnecessary burden.

B. Section-by-Section Discussion

The following section-by-sectionportion of the preamble discusses eachprovision affected. The text of the finalrule is included at the end of thedocument.

Section 75.301 Definitions

The final rule revises the definition ofreturn air to permit operators todesignate certain air courses as returnair courses for the purpose of ventilatingstructures, areas or installations that arerequired to be ventilated to return aircourses and for ventilating seals whenthe air in the air course will not be usedto ventilate working places. Thus, anoperator wishing to split air off of anintake for the purpose of ventilatingshops, electrical installations, or forother purposes, could designate the aircourse into which the split is directedas a return provided the air in the aircourse would not be used to ventilateworking places or other locations,structures, installations or areasrequired to be ventilated with intake air.Commenters generally agreed with thechange. However, one commenterexpressed the concern that air currentsventilating electrical installations couldbe coursed to the conveyor belt entrybefore being coursed to a redesignatedreturn air course, and thus not venteddirectly to a return. The commenterexpressed the opinion that because theair is not vented directly to a returnunder this scenario, the rule would notpermit this practice. MSHA does notagree with the commenter’sinterpretation and the final rule,consistent with § 75.340, permits thispractice.

MSHA does not anticipate thatoperators will need to redesignate aircourses on a routine basis. Whenquestions arise as to the need toredesignate an intake as a return, theoperator should contact the local MSHAoffice. In order that all interestedpersons are made aware when an aircourse is redesignated, the final rulerequires in § 75.372, Mine ventilationmap, that such redesignated air coursesbe shown on the mine’s ventilationmap.

Section 75.310 Installation of MainMine Fans

The main mine fans serve a vital rolein providing ventilation to preventmethane accumulations and possibleexplosions as well as providing minerswith a healthful working environment.Section 75.310 is primarily directed atprotecting the main mine fans from firesand damage in the event of anunderground explosion so that

necessary ventilation can bemaintained. Monitoring of the fans toassure that they are operating properlyis an element of this protection. Thefinal rule for § 75.310 revises paragraphs(a) and (c) of the existing rule. Therevisions address: (1) automatic signalsfor fan stoppage, (2) pressure recordingdevices, and (3) main mine fanmonitoring systems.

Paragraph (a)(3) of § 75.310, like theproposal, requires each main mine fanto be equipped with an automaticdevice that gives a signal at the minewhen the fan either slows or stops. Theexisting rule does not specify where thesignal is to be given. Commenterssupported the proposal stating that asignal alarming at a location away fromthe mine site would rely on overlandcommunication lines to transmit thesignal, with the person receiving thesignal then notifying the mine. Theseoverland communication lines aresubject to weather and other potentialsources of damage, which could resultin a disruption of the communication.Other commenters objected to theproposal, however, stating that theability of a mine operator to consolidatemonitoring of several mines at onesingle location is a very efficient andcost-effective practice and should not bearbitrarily prohibited. Further, theystated that there would be absolutely nodelay in contacting the miners from thiscentral location should a fanmalfunction occur. For clarity and forincreased safety, the final rule requiresthat the signal be given at the mine.MSHA believes that in the case of a fanstoppage, this will assure more timelynotice to miners, and hence, a moreeffective safety response. Therequirement that the signal be given ata surface location at the mine does notpreclude the signal from also beinggiven elsewhere, such as at a centraloffice, as long as it is given at the mine.

Paragraph (a)(3) of § 75.310 requiresthat a responsible person, designated bythe operator, shall always be at a surfacelocation at the mine where the signalcan be seen or heard while anyone isunderground. In addition, theresponsible person must be providedwith two-way communication withworking sections and with otherestablished locations where persons arenormally assigned to work. Commenterssupported the proposal stating that thechanges provide clarification andspecificity. Other commenters agreedwith the proposed concept of two-waycommunication but felt that thewording, ‘‘established locations wherepersons are normally assigned to work’’is ambiguous and subject tomisinterpretation. Some commenters


objected to the proposed requirementstating that (1) it is redundant of§ 75.1600 Communications; (2) properlythe subject of a separate rulemakingunder § 75.1600 or; (3) it is vague,ambiguous, or subjective. Section75.1600 only requires two-waycommunication between the surface andworking sections and does not identifythat this communication must beprovided to a location where a personcan see or hear the fan alarm signal.Commenters suggested that therequirement be revised to morespecifically quantify locations wherepersons are normally assigned to work.MSHA recognizes that, as proposed, thestandard might result inmisinterpretation and the final rule hasbeen reworded to read, ‘‘* * * two-waycommunication with working sectionsand work stations where person(s) areroutinely assigned to work for themajority of a shift.’’

Some, but not all, outby areas wheretwo-way communication would berequired by the final rule include;shops, attended belt transfer points,attended rail car loading points, andattended underground coal storage binsand hoppers. It is not intended that thiscommunications capability be providedin areas where secondary roof support isbeing installed or where rock dust isbeing applied, or at unattendedunderground pumps, or in areas such asreturn air courses, bleeder entries andconveyor belt haulageways other than atbelt transfer points. The requirementthat two-way communication beprovided to work stations wherepersons are routinely assigned to workfor the majority of a shift is intended tohelp assure that these persons receiveprompt notification of fan stoppages.Because these work stations are off theworking section, a lack ofcommunication capabilities could resultin delays in notification and thereforedelays in egress from the mine.

Paragraph (a)(4) of the existing rulerequires that main mine fans beequipped with a pressure recordingdevice or with a main mine fanmonitoring system but exempts fromthis requirement mines permitted toshut down main mine fans under§ 75.311.

The final rule eliminates thisexemption and requires that all mainmine fans be equipped with a pressurerecording device or a main mine fanmonitoring device. For mines notcurrently required to have such adevice, MSHA has provided for a 1 yearphase in period to allow mine operatorstime to effectively plan and implementthe necessary changes. One commentersuggested that all main mine fans at all

mines be required to operate continuallyand further suggested that all main minefans be equipped with pressurerecording devices and main mine fanmonitoring systems. In support of thissuggestion, the commenter stated thatcontinuous fan pressure recordingdevices would have a positive impacton safety at these operations. Suchdevices will provide necessaryinformation to operators and miners atoperations affected by this change.MSHA has not included onecommenter’s suggestion that main minefan monitoring systems be required forall main mine fans. While MSHAsupports and encourages the use of thisadvanced technology the Agency doesnot believe that it is appropriate tomandate it for all mines because dailyfan examinations coupled with pressurerecording devices have proved to beadequate over the years. Also, MSHAdoes not adopt a suggestion that mainmine fans at all mines be required tooperate continuously.

Paragraph (a)(4) of the final rulerequires that when a pressuremonitoring device is used in lieu of apressure recording device, it mustproduce a continuous graph or chart ofthe fan pressure. A hard copy of thecontinuous graph or chart must beprinted at regular intervals of not morethan 7 days. This provision permits theuse of relatively recent advances intechnology for monitoring main minefan pressure provided a continuousrecord of the fan pressure is provided.In the proposal, MSHA specificallysolicited comments as to an appropriatepolling frequency that would provide arecord that is substantially continuous.In response to this request, onecommenter proposed that a pollingfrequency of two seconds is necessary totake full advantage of availabletechnology. This commenter stated thatcontinuously means constant orunbroken and that a continuous recordshould require a polling frequency ofnot greater than 2 seconds. Anothercommenter, an instrumentmanufacturer, suggested that a oneminute sampling interval is definitelyfeasible. Main mine fan monitoring,when used, is often part of a morecomprehensive mine-wide atmosphericmonitoring system (AMS), and torequire that the fan be polled every twoseconds could delay the polling of otherimportant sensors. Additionally,because these pressure monitoringdevices are intended to be used in lieuof the traditional circular pressurerecorder they must provide asubstantially equivalent record.Experience by MSHA engineers

following mine explosions and duringmore routine ventilation survey workhas shown that the accuracy to which a7-day, circular recording chart of thetype normally used can be read is on theorder of several minutes. MSHA wouldexpect that the polling frequency for apressure recording device used in lieuof a pressure recorder would be no morethan one (1) minute.

MSHA received a number ofcomments in response to the proposedrequirement in paragraph (a)(4) thatwhen a pressure recording device otherthan a circular pressure recorder isused, a hard copy of the continuousgraph or chart be generated at not morethan 7-day intervals. Comments rangedfrom requiring daily printouts to notrequiring any printout except whenrequested by an AuthorizedRepresentative of the Secretary. Inresponse to these comments, the finalrule retains the requirement for a hardcopy of the continuous graph or chart begenerated at not more than 7-dayintervals. In light of MSHA’s statedposition to permit records ofexaminations to be stored electronically,the final rule permits the record of mainmine fan pressure to be storedelectronically provided the record issecure and not susceptible to alteration.

Paragraph (c) of § 75.310 specifiesrequirements for main mine fanmonitoring systems if used under§ 75.312. Commenters suggested that therequirements were repetitive, confusing,and would discourage mine operatorsfrom using monitoring systems whichcould provide more protection. MSHAbelieves that the requirements inparagraph (c) are necessary to effectivelymonitor a fan, particularly when thesesystems are used in lieu of daily fanexaminations.

Paragraph (c)(3) of § 75.310 of theproposal would have required that mainmine fan monitoring systems provide,on demand, a printout of the monitoredparameters, including the mineventilating pressure. Severalcommenters objected to the requirementthat a printout be provided ‘‘ondemand.’’ As interpreted by thesecommenters, this standard wouldrequire that the operator provide aprintout at any time it is requested. Asexplained in the preamble to theproposal, ‘‘* * * the monitoring systemwould be required to have the capabilityof providing (emphasis added), ondemand, a printout of the informationbeing monitored. This capability isintended to facilitate the review of theinformation by mine managementrequired in § 75.312(b).’’ Thecommenters misinterpreted the purposefor the standard. MSHA recognizes,


however, the merits of being able toobtain a printout within a reasonableperiod of time. Therefore, the final rulerequires that a main mine fanmonitoring system used to satisfy therequirements of § 75.312 provide aprintout of the monitored parameters,including the mine ventilating pressure,within a reasonable period, not toexceed the end of the next scheduledshift during which miners areunderground.

Paragraph (c)(5) of § 75.310 requiresthat two-way communication beprovided between a surface location atthe mine where the signals from the fanmonitoring system can be seen or heardand working sections and otherestablished locations where persons arenormally assigned to work for themajority of the shift. Except for minoreditorial changes, this requirement isthe same as the proposal. Comments onthis proposal were the same ascomments on proposed paragraph (a)(3).Several commenters supported theproposal stating that the changesprovide clarification and specificity.Other commenters agreed with theproposed concept of two-waycommunication but felt that thewording, ‘‘established locations wherepersons are normally assigned to work’’is ambiguous and subject tomisinterpretation. Some commentersobjected to the proposed requirementstating that (1) it is redundant of§ 75.1600 Communications; (2) properlythe subject of a separate rulemakingunder § 75.1600 or; (3) it is vague,ambiguous, or subjective. Section75.1600 only requires two-waycommunication between the surface andworking sections and does not identifythat this communication must beprovided to a location where a personcan see or hear the fan alarm signal.Commenters suggested that therequirement be revised to morespecifically quantify locations wherepersons are normally assigned to work.MSHA recognizes that, as proposed, thestandard might result inmisinterpretation and the final rule hasreworded the proposal to read, ‘‘* * *two-way communication with workingsections and work stations whereperson(s) are routinely assigned to workfor the majority of a shift.’’

Some, but not all, outby areas wheretwo-way communication would berequired by the final rule include;shops, attended belt transfer points,attended rail car loading points, andattended underground coal storage binsand hoppers. It is not intended that thiscommunications capability be providedin areas where secondary roof support isbeing installed or where rock dust is

being applied, or at unattendedunderground pumps, or in areas such asreturn air courses, bleeder entries andconveyor belt haulageways other than atbelt transfer points. The requirementthat two-way communication beprovided to work stations wherepersons are routinely assigned to workfor the majority of a shift is intended tohelp assure that these persons receiveprompt notification of fan stoppages orother problems with the fan that mightrequire withdrawal of miners. Becausethese work stations are off the workingsection, a lack of communicationcapabilities could result in delays innotification and therefore delays inegress from the mine.

Section 75.311 Main Mine FanOperation

The main mine fan provides thepressure that causes air to move throughthe mine to dilute and carry awayexplosive and toxic gases, dusts andfumes. As such it is the most importantpart of the ventilation system. Section75.311 requires fans to be continuouslyoperated to provide constant ventilationto underground areas and specifiesprecautions for planned fan stoppages.It also addresses the repair of main minefans, monitoring of fan signal devices onthe surface, and protection against firesaround fans and intake air openings.

The final rule revises paragraph (d) of§ 75.311, which addresses thenotification of mine officials of anyunusual variance in mine ventilationpressure and requires the prompt repairof electrical or mechanical deficiencies.The final rule requires immediatenotification and the prompt institutionof corrective action or repairs.

Commenters suggested deletion of theword ‘‘unusual’’ maintaining that thisterm makes the requirement vague andsubject to different interpretations.These commenters suggestedsubstituting the phrase, ‘‘that couldmaterially affect the safety and health ofpersons in the mine’’ to describe thetype of pressure variance that wouldrequire action. In making thisrecommendation, the commenters citedsimilar language in existing§ 75.324(a)(1) that, according to thecommenters, is understood throughoutthe coal mining community. Section75.324(a)(1) concerns alterations of themain ventilation air current or any splitof the main air current. The final ruledoes not adopt this recommendation.Minor fluctuations in fan operatingpressure are normal; however, unusualchanges can be indications of changes infan operation or changes underground,such as roof falls or loss of ventilationcontrols, that require prompt attention

and corrective action. In addition,MSHA has 25 years of experience withthe phrase ‘‘unusual variances in mineventilation pressure’’ and is unaware ofsignificant difficulties with thisterminology.

Commenters questioned whatconstitutes an ‘‘electrical or mechanicaldeficiency’’ for the purposes of § 75.311.The purpose of the standard is to assurethat a problem with main mine fans iscorrected promptly and that the properpersons are notified that the problemexists. The types of electrical ormechanical deficiencies requiring actionunder paragraph (d) are those that caninterfere with mine ventilation. Inaddition, MSHA has 25 years ofexperience with the phrase ‘‘electricaland mechanical deficiencies’’ and is,again, unaware of any significantdifficulties with the use of thisterminology during this time frame.

Commenters also addressed theproposal that the ‘‘mine superintendent,assistant mine superintendent, or mineforeman’’ be notified immediately whenan unusual variance in mine ventilationpressure is observed, or when anelectrical or mechanical deficiency in amain mine fan is detected. The finalrule does not retain the minesuperintendent or the assistant minesuperintendent as mine officials to benotified. Commenters stated that thisprovision provides a measure of safetyto the miners by requiring that specificmine managers be notified of possiblemain mine fan problems, while theexisting standard specifies that such asituation must be investigated. Othercommenters, however, suggested thatthe persons identified for notificationunder the proposal may not be the mostqualified to handle the problem. Theyalso indicated that the notificationrequirement could unnecessarily delayappropriate action by other responsiblepersons. The commenters further statedthat the mine superintendent orassistant mine superintendent may notbe at the mine and that a certifiedperson would be in charge who shouldbe permitted to take the appropriateaction. The proposed requirement thatcertain mine managers be notifiedimmediately was not intended torequire that these individuals personallytake the necessary actions to respond tothe problem with the main mine fan.Neither was it intended that they benotified of such a problem, to theexclusion of all others. The objective ofthe rule is to assure that the appropriateactions are taken as soon as possible.Additionally, notification of specifiedmine officials is intended to assure thatthose persons who are responsible forthe mine are aware of the problem. The


final rule, therefore, retains therequirement that certain mine managersbe notified of any unusual variance inthe mine ventilation pressure or if anelectrical or mechanical deficiency of amain mine fan is detected.

The final rule does, however, deletereference to notification of the minesuperintendent or assistant minesuperintendent. As discussed in relationto the countersigning of records, themine superintendent is quite often nota certified person and is onlyperiodically present at the mine. Inaddition, consistent with other sectionsof the final rule and recognizing that theterm mine foreman is not used at somemines, the final rule requires that if anunusual variance in the mineventilation pressure is observed, or if anelectrical or mechanical deficiency of amain mine fan is detected, the mineforeman or equivalent mine official, orin the absence of the mine foreman orequivalent mine official, a designatedcertified person acting for the mineforeman or equivalent mine officialshall be notified immediately. As withthe proposal, the final rule requires thatappropriate action or repairs shall beinstituted promptly. It is not intendedthat the appropriate action or repairs bedelayed until the mine foreman orequivalent mine official is notified.

During a series of informationalmeetings held by MSHA followingpublication of the existing rule,questions arose concerning theoperation of back-up fans. Forinformational purposes, the preamble tothe proposal included a detaileddiscussion of questions about theoperation of back-up fans under theventilation regulations and solicitedcomments. MSHA did not propose anyrule changes, nor does the final rulecontain specific provisions for back-upfans. When a back-up fan operates inplace of the main mine fan, the back-upfan is considered to be a main mine fanand all subpart D requirements for mainmine fans are applicable.

Section 75.312 Main Mine FanExaminations and Records

Proper operation of main mine fans iscritical to mine ventilation and theprevention of methane accumulationsand possibly methane explosions.Recognizing the importance of the mainmine fan, § 75.312 requires that eachmain mine fan be examined at leastonce each day that the fan operatesunless the fan is continuouslymonitored with a main mine fanmonitoring system. Through dailyexaminations or continuous monitoringof critical parameters, the operator candetermine if problems with the fan are

developing and correct these problemsbefore ventilation is affected.

The final rule removes existingparagraph (g)(2), revises existingparagraphs (a), (b)(1), (c), (d), (g)(1) and(h), redesignates existing paragraph (f)as (f)(1), and adds new paragraphs (f)(2)and (g)(2). Paragraph (a) of the final rule,like the existing rule, requires dailyexamination of main mine fans unless afan monitoring system is used. Inaddition, paragraph (a) specifies that anexamination of the main mine fan is notrequired on days when no person goesunderground. An examination of thefan, however, is required prior toanyone entering the mine. The purposeof this examination, as stated inparagraph (a), is to assure the electricaland mechanical reliability of the fan.

When a fan monitoring system isused, the final rule requires a dailyreview of the data from the monitoringsystem to be made, except on days whenno person goes underground. A reviewof the data from the monitoring systemmust be completed, however, prior toanyone entering the mine.

Fan examinations or review of fanmonitoring system data are required tobe performed by a trained persondesignated by the operator.

Commenters questioned the use of theterm ‘‘assure’’ in paragraph (a) whenreferring to the electrical andmechanical reliability of main minefans. MSHA uses the term ‘‘assure’’ inthis context as defined in Webster’sThird New International Dictionary,Unabridged, 1993 edition, to mean, ‘‘tomake safe, to give confidence to.’’ Thesense of this definition is consistentwith the intended purpose of theexamination. The term does not mean to‘‘guarantee’’ safety, as suggested by onecommenter.

Commenters suggested that the finalrule require the examination of mainmine fans for proper operation beconducted by an individual trained aspart of the mine operator’s training planrequired by MSHA’s comprehensivetraining regulation in part 48 of 30 CFR.Other commenters understood theproposal to require training of fanexaminers under part 48, and objectedto such a requirement. Thesecommenters suggested that the personconducting the fan examination be onewho has received training throughexperience or has been trained by anexperienced person, or by the fanmanufacturer. The final rule does notrequire fan examiners to be trained aspart of the operator’s part 48 trainingplan. Instead, the final rule specifiesthat fan examiners must be trainedsufficiently to have the skill andknowledge to ascertain whether the fan

is in proper working order,mechanically and electrically.

Paragraph (a) requires a daily physicalexamination of the main mine fan,unless a fan monitoring system is used.If a fan monitoring system is used,paragraph (b) requires a weekly physicalexamination of the main mine fan, aweekly test of the monitoring system,and a daily review of the main mine fanmonitoring data. Commenters suggestedthat even if a main mine fan is equippedwith a monitoring system, the fanshould still be subject to daily physicalexaminations because a fan monitoringsystem is not capable of disclosing allconditions that a physical inspectioncould disclose. The final rule does notadopt this suggestion. A weeklyphysical examination of the fan and atest of the monitoring system coupledwith a daily review of the monitoringdata provides reasonable assurance thata mine fan is operating reliably.Commenters suggested that theproposed requirement of paragraph(b)(1) requiring a daily review of mainmine fan monitoring system data isunnecessary and redundant. Thesecommenters suggested that the systemneed only be capable of producing aprintout because the systems wouldautomatically alarm anytime anelectrical or mechanical deficiencyexists. Requiring a daily review of themonitoring system data, according tothese commenters, could discourage theuse of improved technology. Othercommenters noted that operatorscurrently using fan monitoring systemsconduct a daily review of the data at thepresent time and that the requirementsto review the data would provide anadditional measure of safety for theminers. MSHA believes that a dailyreview of data from fan monitoringsystems is needed to assure that minemanagement is made aware of anyoperational changes or trends inmonitored parameters. Main mine fansprovide the source for mine ventilationand, therefore, are critical to miners’safety. As discussed earlier, these dailyreviews of data are designed tocomplement the physical examinationsof the fan.

The final rule adopts the requirementsof proposed paragraphs (b)(1)(ii) (A) and(B) and requires that when a fanmonitoring system is used as providedunder paragraph (a), a trained persondesignated by the operator must test thesystem for proper operation at leastevery 7 days. Commenters objected thatit is redundant because a fan monitoringsystem is capable of monitoring itselfand can automatically provide awarning when a fan malfunction occurs.These commenters also stated that if the


system is continuously operated, thesystem is self-tested for properoperation several times a minute andthat the 7-day test is unnecessary. Thecommenters suggested that the 7-daytest only be conducted if the fanmonitoring system is not continuouslyoperated. For continuously operatingfans an examination of the fan shouldmore appropriately be conductedmonthly, according to thesecommenters. Requiring more frequentchecks the commenters maintain woulddiscourage the use of fan monitoringsystems.

The final rule does not adopt thesesuggestions. While MSHA encouragesthe use of fan monitoring systems,excessive reliance on the self-monitoring features of these systems isincompatible with the importance ofreliable operation of main mine fans.MSHA does not anticipate that the finalrules for examination requirements willdiscourage the use of fan monitoringsystems. Main mine fans without amonitoring system are required to beexamined daily, while fans withmonitoring systems are required to beexamined every seven days.

Paragraphs (c) and (d) of § 75.312 ofthe final rule continue in effect therequirements that tests of the automaticfan signal device and automatic closingdoors, when these doors are required, beconducted at intervals not to exceed 31days. The specified means of testingthese devices and doors is by stoppingthe fan. The proposal would havepermitted an alternative test notinvolving stopping the fan if thealternative method provided the samelevel of assurance that the signal deviceor door would function as intendedduring fan stoppages. Two commentersfavored the proposal and suggested thatthere is no need to approve alternatemeans of testing fan signal devices inthe mine ventilation plan. Thesecommenters expressed the opinion thateach authorized representative shouldbe capable of ascertaining the validity ofthe alternative method. The commentersdid not make a similar suggestionrelative to the alternative meansprovision proposed in paragraph (d) forautomatic closing doors. Anothercommenter opposed the use ofalternative tests stating that it would bepremature to adopt a provision for analternative test to stopping the fan whensuch a test has not as yet beendeveloped. MSHA has reconsidered theproposal and the final rule continues torequire that the tests of fan signaldevices and automatic closing doors beconducted by stopping the fan. Shouldan operator develop an alternativemethod that provides the same level of

protection as stopping the fan, thepetition for modification process isavailable for an operator to obtainapproval.

Paragraphs (c) and (d) permitunderground power to remain energizedduring fan signal and automatic closingdoor testing, notwithstanding therequirements of § 75.311. If the fan isnot restarted within 15 minutes, thefinal rule requires that undergroundpower be deenergized and no one ispermitted to enter any undergroundportion of the mine until the fan isrestarted and an examination isconducted. Additionally, paragraphs (c)and (d) require that only personsnecessary to evaluate the effect of thefan stoppage or restart, or to performmaintenance or repair work that cannototherwise be done while the fan isoperating, are permitted underground.

Some commenters objected to limitingthe persons who can be undergroundduring fan signal and closing door tests.Other commenters objected to anyonebeing permitted underground during thestoppage of a fan to conduct therequired tests. These commentersexpressed the opinion that all necessarywork can be performed with the fanoperating and therefore, when a fan isshut down to test the fan signal deviceor the automatic closing doors no oneshould be underground.

Some work, such as workingimmediately inby a blowing fan, couldplace workers at risk by exposing themto extreme temperatures, effects of thehigh velocity air stream, or excessivenoise levels when the fan is operating.In addition, repair work within a shaftcan more safely be done when a fan isstopped. The rule, therefore, retains theexception that permits personsunderground during intentional fanstoppages to evaluate the effect of thefan stoppage or restart, or to performmaintenance or repair work that cannototherwise be done while the fan isoperating.

Paragraphs (c) and (d) of the final ruleare reworded to clarify that during therequired tests, power circuits mayremain energized only if no person isunderground. Therefore, if an operatorelects to evaluate the effect of the fanstoppage or restart, or to performmaintenance or repair work that cannototherwise be done while the fan isoperating, simultaneous with the testsrequired, power circuits must bedeenergized in accordance with§ 75.311(b)(3). Additionally, inaccordance with § 75.311(b)(2), allmechanized equipment must be shutoff.

Paragraph (f)(1) of the final ruleretains the longstanding requirement

that the person performing main minefan examinations certify by initials anddate at the fan or another locationspecified by the operator that theexaminations were made. Eachcertification is required to identify themain mine fan that was examined.When daily fan examinations areconducted, daily certification isrequired. When a main mine fanmonitoring system is used and fanexaminations are conducted at 7 dayintervals, certification is required eachtime the fan is examined.

One commenter offered suggestedwording that would eliminate theoption of certifying that the examinationwas completed at a location other thanthe fan being examined. This suggestionhas not been adopted and the final ruleretains the flexibility for certifications tobe made away from the fan.

Paragraph (f)(2) of the final rulerequires that when a main mine fanmonitoring system is used, a dailyprintout of the system’s data must becertified to indicate that the dailyreview was completed. While somecommenters generally agreed with thisrequirement other commenterssuggested that an alternative should beprovided for systems which arecontinuously operated and supervised.In such cases, the commenters suggestedthat immediate notification of the mineforeman when a deficiency arises wouldbe appropriate, together withmaintaining the internal records of datagathered by the systems for one year.

The suggested alternative is notincluded in the final rule. MSHAbelieves that documentation thatmonitoring system data is beingreviewed is necessary to providereasonable assurance that minemanagement is aware, on a timely basis,of the operating condition of the fanbeing monitored. However, to reducethe burden of this requirement, the finalrule in paragraph (f)(2) does permit theelectronic certification of the review ofthe data generated by a fan monitoringsystem. As with electronically keptrecords, the rule would require that theelectronic certification includehandwritten initials and dates. Adiscussion of comments concerning theuse of computers to maintain recordscan be found in the General Discussionof this preamble.

Paragraph (g)(1) of § 75.312 requiresthat by the end of the shift on which theexamination is made, persons makingmain mine fan examinations mustrecord all uncorrected defects foundduring the examination that may affectthe operation of the fan. The rule alsospecifies that records be maintained ina book that is secure and not susceptible


to alteration, or electronically in such amanner as to be secure and notsusceptible to alteration. The proposalwould have required all defects foundduring the main mine fan examinationthat may affect the operation of the fanto be recorded whether corrected oruncorrected.

Some commenters objected torecording defects that ‘‘may’’ affect theoperation of the main mine fan, andsuggested only defects that do affect theoperation of the main mine fan and thatare not corrected by the end of the shift,need to be recorded.

Some commenters asserted that arecord of ‘‘all’’ defects should berequired in order to identify recurringproblems that may lead to biggerproblems. These commentersinterpreted the proposal to require sucha record. The final rule is intended toaddress problems found during fanexaminations that may indicate moreserious defects and ultimately lead to afan failure and that cannot be correctedby the end of the shift. The objective isto record defects of a nature andseriousness that could result in a fanfailure, but not to record defects that areso minor that it would be unreasonableto expect fan failure to result. Anothercommenter stated that recording alldefects that may affect fan operationwould result in excessive paperwork oflittle value. This commenter alsosuggested that if mine ventilation doesbecome ineffective, the workers are tobe withdrawn from the mine. MSHA issensitive to concerns aboutrecordkeeping. Therefore, the final rulerequires that all uncorrected defectswhich are found during the examinationthat may affect fan operation berecorded. In this manner, miners on theoncoming shift are aware of problemswith the fan that potentially couldimpact underground ventilation.

Commenters supported the use ofelectronic media as a substitute forspecific types of record books.Commenters pointed out that almost allsuch systems incorporate recordkeepingfunctions and that significant variancesfrom the norm are easily noted. Theyconcluded that the computer monitoringsystems provide superior protection forthe miners. The final rule permits, inparagraph (g)(1), the use ofelectronically stored records for mainmine fan examinations provided therecords are secure, are able to capturethe information and signatures required,and are accessible to the representativeof the miners and the representatives ofthe Secretary.

As with other records required by thisrule, paragraphs (g)(2) and (g)(3) requirethat records required by § 75.312 must

be made in books that are secure andnot susceptible to alteration, orelectronically in such a manner as to besecure and not susceptible to alteration.A detailed discussion of record booksand the use of computers to maintainrecords can be found in the GeneralDiscussion of this preamble.

Paragraph (g)(2) of the existing rulerequires that at mines permitted to shutdown main mine fans under § 75.311, ifa pressure recording device is not used,a record shall be made, in a bookmaintained for that purpose, of the timeand fan pressure immediately before thefan is stopped, and after the fan isrestarted and the fan pressure stabilizes.The final rule does not retain thisrequirement in light of the newrequirement of § 75.310(a)(4) that allmain mine fans be provided with apressure recording device or an optionof the use of a fan monitoring system.This new requirement eliminates theneed for an additional record of the timeand fan pressure made immediatelybefore the fan is stopped and after thefan is restarted and the fan pressurestabilizes. This information is obtainedfrom the pressure recording chart,which records the pressurecontinuously and automatically, thusmaintaining the protection afforded theminers.

Paragraph (h) of the final rule requiresthat the records required by § 75.312 bemaintained at a surface location at themine for one year and be made availablefor inspection by authorizedrepresentatives of the Secretary and therepresentative of miners. Commentswere generally favorable on thisproposal. A discussion of commentsconcerning the use of computers tomaintain records can be found in theGeneral Discussion of this preamble.

As with the other provisions of thefinal rule allowing electroniccertification or recordkeeping, sufficientprotections have been included so thatthere is no reduction in protection fromthe existing standards.

Section 75.313 Main Mine FanStoppage With Persons Underground

Section 75.313 was stayed by MSHAas explained in the introductory sectionof this preamble. Generally, thisstandard is concerned with protectingminers from the danger introducedwhen the main mine fan stops, such aswhen there is a loss of power. Underthese circumstances, mine ventilation isinterrupted, permitting gases such asmethane to accumulate. Theseconditions can lead to an explosionignited by electric circuits or theoperation of equipment.

Paragraph (a)(3) of the final rulerequires that if a main mine fan stops,everyone shall be withdrawn from theworking sections and from areas wheremechanized mining equipment is beinginstalled or removed. The language ofthe final rule is identical to the wordingof stayed § 75.313 (a)(3). An in-depthdiscussion of provisions concerning theinstallation and removal of mechanizedmining equipment is presented in theGeneral Discussion section of thispreamble.

The final rule revises paragraphs(c)(2), (c)(3), (d)(1)(i) and, (d)(1)(ii) of thestayed standard. Paragraphs (c)(2) and(c)(3) require that when a main mine fanstops with persons underground, theunderground electric power circuitsshall be deenergized and mechanizedequipment shall be shut off. These rulesfurther recognize an exception tofacilitate miners’ evacuation from themine. The exception temporarilypermits some circuits to remainenergized and some mechanizedequipment to not be shut off, providedthese circuits and mechanizedequipment are necessary to withdrawpersons from the mine and are locatedin areas where methane is not likely tomigrate to or accumulate. These circuitsmust be deenergized and themechanized equipment must be shut offas persons are withdrawn. The final rulediffers from the stayed standard bylimiting the exception permitting theuse of these circuits or equipment toareas where methane is not likely tomigrate to or accumulate.

Paragraph (d)(1)(i) requires that whena fan stoppage lasts for more than 15minutes a preshift-type examinationmust be conducted before persons otherthan designated examiners, arepermitted to enter any underground areaof the mine. Examiners are permitted tore-enter the underground area of themine from which miners have beenwithdrawn only after the fan hasoperated for at least 15 minutes unlessa longer period of time is specified inthe mine ventilation plan. Paragraph(d)(1)(ii) requires that when a fanstoppage lasts for more than 15 minutes,underground power circuits are not tobe energized and nonpermissiblemechanized equipment is not to bestarted until a preshift-type examinationis conducted, except that designatedcertified examiners may usenonpermissible transportationequipment in intake airways to facilitatethe conduct of the requiredexamination.

Some commenters suggested thatactions following fan stoppages are besthandled on a mine-by-mine basisthrough a plan approval process. Along


these lines, commenters suggested thatthe fan stoppage plan approval processpreviously used by MSHA should beused with only minor modification toassure that plans do not becomestandardized, that is, model the rule ona past standard with criteria forapproval of fan stoppage plans. Othercommenters, while supporting theconcept of fan stoppage plans, proposedto tie the submission and approval ofsuch plans to total mine ventilationsurveys and computer simulationsconducted by the operator every threemonths. According to one commenterthe data provided by these surveyswould be used to determine theadequacy of a fan stoppage plan.

The final rule does not adopt thesuggestions of the commenters for minefan stoppage plans. One objective in thisrulemaking is to reduce the need forpaperwork, such as plans, wherereasonable, uniform requirements canbe developed. The final rule establishesthe general requirement that after a fanstoppage lasting more than 15 minutes,mine power and equipment is to be shutdown. However, experience shows thatusing transportation equipment tofacilitate mine evacuation is oftennecessary, provided this is done wheregas is not likely to accumulate, andcircuits are deenergized on the way outof the mine.

Some commenters suggested that therequirements in paragraphs (c)(2) and(c)(3) limiting the use of transportationequipment to areas and haulageways‘‘where methane is not likely to migrateto or accumulate’’ are inconsistent withcertain state laws. As support for thisassertion, the commenters gave theexample of the state of Illinois’requirements for evacuating minesfollowing an interruption in ventilation,which does not expressly recognizelimited use of power and equipment tofacilitate evacuation. State mine safetylaws, including Illinois’, are similar tothe final rule provisions for evacuationafter a mine fan stoppage. As a generalrule, state mine safety regulations thatare more stringent than MSHAstandards are not considered to be inconflict with federal regulations, andthe more stringent safety requirementapplies. In this case, if the Illinoisregulation would not permit temporaryuse of power and equipment to facilitateevacuation, then the state law would notbe inconsistent with MSHA.

Several commenters objected to thewording, ‘‘where methane is not likelyto migrate to or accumulate,’’ inparagraphs (c)(2) and (c)(3), as beingvague. Other commenters stated that therule’s requirement was simply goodpractice that would be heeded by

prudent mine managers. MSHA agreesthat the terms and objectives of the finalrule are understood in the miningcommunity, and believes that thedetermination of whether methane maymigrate from adjacent areas and entertravelways and haulageways used byminers during withdrawal should bemade on a mine-by-mine basis.Therefore, the final rule retains theexception that power circuits mayremain energized and mechanizedequipment may be operated only iflocated in areas where methane is notlikely to migrate to or accumulate.

Some commenters stated that historydoes not support the need for therequirements of paragraphs (c)(2) and(c)(3). Mine fan stoppagesunquestionably result in the existence ofunventilated areas and may result inhighly hazardous methaneaccumulations. Although there havebeen a limited number of ignitions/explosions directly attributable to theoperation of transportation equipmentduring a fan stoppage, the true measureof the potential hazard addressed by thisstandard can be seen in the ignitionsand explosions that were the result ofthe operation of transportationequipment in unventilated areas.Examples of such types of accidentsinclude: The 1972 Itmann No. 3explosion, in which 5 miners died; the1976 Scotia Mine explosion, in which15 miners died; the 1982 VirginiaPocahontas No. 6 Mine explosion inwhich 1 miner was injured; the 1983McClure No. 1 Mine explosion, inwhich 7 miners died; the 1983 HomerCity Mine explosion in which a mineexaminer was killed; the 1983Greenwich Collieries No. 1 Mineexplosion in which 3 miners were killedand 4 miners were injured and; the 1993explosion at the Buck Mountain No. 2Mine in which 3 miners were injured.Given this history of explosions, itwould not be prudent to permit electriccircuits to remain energized andmechanized equipment to be operatedin areas or haulageways where methaneis likely to migrate to or accumulateduring a fan stoppage.

One commenter stated that the in-mine test necessary to determine thelikelihood of methane migration couldonly be done with the fan stopped. Thecommenter questioned whether minerswould be permitted underground duringthe tests. To the extent the tests requirethe main mine fan to be turned off,persons would be allowed undergroundto evaluate the effect of the fan stoppageor restart.

Paragraphs (d)(1)(i) and (ii) addresssafety precautions for reentering themine after ventilation is restored. Key

objectives of these standards are theprotection of the examiners and thesafety of miners returning to work.

As proposed, paragraph (d)(1)(i)would have required that when a fanstoppage lasts for more than 15 minutesa preshift- type examination beconducted covering the requirements of§ 75.360(b) through (e) before persons,other than designated examiners, enterany underground area of the mine.Commenters suggested that to providethe level of protection desired, acomplete preshift examination,including the certification andrecordkeeping requirements of§ 75.360(f) through (g), should berequired. Commenters pointed to theneed for miners reentering evacuatedareas to be able to determine if the areahad been examined and urged that thefinal rule require the examiner to certifyby initial, date and time the areasexamined.

MSHA agrees that clear notice tominers about which areas have beenexamined is necessary and consistentwith the objectives of the rule. The finalrule, therefore, adopts the proposal. Arecord of the hazardous conditionsfound by examiners is required under§ 75.363 of the final rule. This recordserves the purpose of providing minemanagement with the informationnecessary relative to the existence andcorrection of hazardous conditions inthe mine. The final rule incorporatesthese requirements by specifying thatthe scope of the examination beconducted as described in § 75.360(b)through (e).

Under paragraph (d)(1)(i) no one otherthan designated certified examinerswould re-enter any underground area ofthe mine until the entire examination iscompleted. Commenters suggested thatparagraph (d)(1)(i) be revised to permitpartial examinations following fanstoppages and restarts under certainconditions. Under this suggestedapproach, the examination would focuson the effectiveness of the mine’sventilation system and methaneaccumulations in travelways, workplaces or other areas where miners willwork following the interruption ofventilation. One commenter furthersuggested that an exception to thisexamination be provided for noncoalproducing shifts, where persons are towork in the shaft, slope, drift, or on theimmediate shaft or slope bottom area.The commenter suggested theexamination following a fan stoppagecould be limited to this area.

The final rule does not adopt thisapproach. Limiting the scope ofexaminations following an interruptionin mine ventilation to general


ventilation effectiveness and methaneaccumulation would not focus on likelyareas of concern. For example, noexamination for hazards would berequired, and no air measurements todetermine if the air is moving in itsproper direction and at its normalvolume would be required. As to thearea of the mine required to beexamined, only those places whereminers will return to work and the routeof travel used to reach these places mustbe examined. Thus, the final rule issufficiently flexible to meet thecommenter’s concerns about noncoalproducing shifts.

A question arose during publicmeetings as to the meaning of the termon-coming shift in § 75.360 whenapplied to § 75.313. For the purposes of§ 75.313(d)(1)(i) and (ii) the term‘‘persons on the on-coming shift’’ isinterpreted as meaning persons on theshift on which the fan is restarted. If afan outage extends from one shift intoanother, a preshift examination asrequired by § 75.360 must be completedbefore any person, except certifiedexaminers designated to conduct theexamination, enters the mine.

Commenters also suggested that thefinal rule specify a minimum time forthe fan to run before examiners re-enterthe mine so that examiners are notunduly exposed to danger. Severalcommenters observed that this is ageneral practice in the industry.

MSHA agrees that an importantmeasure of safety is gained by allowingthe mine fan to run sufficiently long tobegin reventilating the mine beforeanyone enters. The final rule, therefore,provides designated certified examinersshall enter the underground area of themine from which miners have beenwithdrawn only after the fan hasoperated for at least 15 minutes unlessa longer period of time is specified inthe approved mine ventilation plan. The15 minute provision will permit re-ventilation of entries in whichexaminers will travel to take place andthe examiners will then be traveling intothe mine in fresh air.

Proposed paragraph (d)(1)(ii) wouldhave required that when a fan stoppagelasts more than 15 minutes undergroundpower circuits are not to be energizedand nonpermissible equipment is not tobe started until a preshift-typeexamination is completed. Commentersobjected to the proposal for variousreasons. One commenter suggested thatbefore power is permitted to beenergized a complete ventilation surveyshould be required. Other commentersfocused on the practical considerationsinvolved in conducting examinationsand urged that use of nonpermissible

equipment for the transportation ofexaminers be permitted.

As revised, paragraph (d)(1)(i)requires that the main fan whenrestarted run for at least 15 minutes sothat restoration of mine ventilation isunderway before anyone enters themine. Once this is accomplished,electrical circuits in shafts and slopescan be energized safely as these areasare the first places to be reventilated byfresh air. Accordingly, the final rulepermits these circuits to be re-energizedafter the mine fan has run for at least 15minutes.

The final rule also permits examinersto use nonpermissible equipment fortransportation during the examination.The proposal would have prohibitedthis practice. Some commenterssupported the proposed prohibitionciting two mining accidents involvingnonpermissible equipment inunventilated areas. Other commentersobjected to the proposal not to allow theuse of nonpermissible equipment tofacilitate examinations following therestart of a main mine fan. Thesecommenters stated that travelways andequipment roadways can be examinedand tested for the presence of methane,the results of the examination calledout, and typical nonpermissibletransportation equipment placed intooperation to expedite the examination ofthe mine.

After considering all of the comments,MSHA has revised the proposal and thefinal rule permits the use ofnonpermissible transportationequipment, in intake airways, tofacilitate making the examinations afteran interruption in mine ventilation.Using nonpermissible equipment in thisfashion, in nonventilated areas, hasbeen a demonstrably safe practice formany years in the industry. In addition,the requirement of running the fan for15 minutes before reentering the mine,together with keeping the transportationequipment in the intake airways wherethe main ventilating current travels first,provides the desired level of safety.

Under proposed paragraph (d)(2), ifventilation was restored to the minebefore miners reached the surface, allminers would have been required tocontinue traveling to the surface. Asproposed, designated certifiedexaminers would have been permittedto remain underground for the purposeof beginning the required examination.The final rule does not adopt theproposal and retains the language of theexisting standard.

While supporting the requirementthat miners continue to the surface aftera fan is restarted, some commentersobjected to permitting certified persons

to remain underground. Thesecommenters also took the position thatonce a fan has been off for more than 15minutes, all efforts to restart the fanshould be suspended, unless it is knownthat it is safe to restart the fan. Othercommenters expressed significantlydifferent views on both issues. Anumber of commenters supportedrestarting the fan as soon as possiblebecause the longer it is off, the greaterthe potential hazard. MSHA concurswith this reasoning and the final ruleadopts this approach.

On the issue of requiring theevacuation to continue once it hasbegun until the fan is restarted, evenwhen ventilation is restored, a numberof commenters objected that such arequirement would result inunnecessary delays and may result inadditional safety risks. One commenterstated that the proposal would not allowfor the variables that exist from mine tomine. Several commenters suggestedthat if the operator has reason to believethat the time frame of the fan stoppagewould be less than the travel time orequivalent, the dangers of travelingoutby into possible pockets ofdangerous gas buildup (or other travelhazards) far outweigh the dangers ofstaying on the section in intake air backfrom the face. This would also allow theminers to remain on the section andproceed to the working places after thefan has restarted and the working placeshave been examined by a certifiedperson.

MSHA disagrees with this position. Insome mines, the time to travel from theoutside to the working sections canapproach 1 hour. Following theapproach suggested, miners wouldremain on the section in an unventilatedmine for up to 1 hour. If at the end ofthis time ventilation is still not restored,it is unclear whether the miners thenproceed to the surface, traveling throughthe same area the commenter suggestedmight be hazardous some 45 minutesbefore.

The commenters stated further that,‘‘Forcing miners to walk out of the minecould take hours and unnecessarilydelay the restoration of ventilation andresumption of operations.’’ While theremay be instances where the timerequired to withdraw miners isincreased, the requirements inparagraphs (c)(2) and (c)(3) have noimpact on the restoration of ventilation.In fact, MSHA’s position is thatventilation should be restored as soon aspossible following a fan stoppage.

Lastly, a number of commenterssuggested that when ventilation isrestored during evacuation, minersshould be permitted to remain where


they are and return to working areasafter an examination of inby areas iscompleted. These commenters statedthat no additional measure of safety isgained by requiring miners to continueto the surface if ventilation has beenrestored and the area in which theminers are located is free of hazards.MSHA agrees and has retained thelanguage of the existing rule. Byretaining the existing language, thegeneral practice of miners stopping theirevacuation and waiting for examiners tocomplete their work will continue.Under this approach, miners remain ina safe location while ventilation of themine is restored. They do not return toany area of the mine until it has beendetermined to be safe. The final ruledoes not prevent mine operators fromhaving miners continue to the surface ifthey so choose. Regardless of whetherminers remain where they are orcontinue to the surface, paragraph(d)(1)(i) of the final rule requires that thefan operate for at least 15 minutes beforethe examination of the areas from whichminers have withdrawn is examined.

Section 75.320 Air Quality Detectorsand Measurement Devices

Section 75.320 establishes thestandards for the devices relied upon totest for the presence of methane andother dangerous gases that canaccumulate in a mine. It generallyrequires that these devices be approvedand maintained in permissible andproper operating condition.

The final rule adds a new paragraph(e). It requires that maintenance ofinstruments required by paragraphs (a)through (d) of § 75.320 to detect andmeasure air quality be done by a trainedperson. The final rule does not includethe proposal that before each shift careshall be taken to assure the permissiblecondition of the air quality detectorsand other measurement devices to beused during the shift. MSHA hasconcluded that this requirement wouldhave been redundant with paragraph (a)and is unnecessary. The final rulepermits an operator to send instrumentsto a repair facility or to themanufacturer for regular servicing.Commenters at the informationalmeetings and in later discussions on theexisting rule stated that maintenance bytrained persons should be specified andthat requiring only that air qualitydetectors and other measurementdevices be maintained in permissiblecondition would not be sufficient. Theystated that without a requirement formaintenance to be done by a trainedperson, similar to that which existed inthe previous standard, a person withless than the necessary understanding of

the instrument and the permissibilityrequirements might be assigned the task.

Several commenters suggested thatthe requirements of paragraph (e) areredundant with general requirementsfound elsewhere in the standards andare unnecessary. Other commenters feltthat the current performance standard isadequate, but that the meaning of‘‘assure’’ is unclear. Still othercommenters indicated that theassurance of permissibility is properlythe responsibility of the user. Onecommenter noted that the instrumentsare intrinsically safe and that themanufacturer’s instructions aresufficient. MSHA agrees that the generalrequirement under paragraph (a),together with requiring trained persons,is adequate.

Another commenter suggested that aformal written maintenance program berequired. Under this suggestion, theprogram would be subject to MSHAapproval and would include records ofall maintenance and calibrations to bemade by the end of the shift. Thiscommenter also suggested that existingparagraph (a) be revised to provide formore frequent calibration by insertingthe phrase ‘‘* * * or more often ifnecessary * * *.’’ This suggestion hasnot been adopted since compliance withthe proper operating and permissibilityprovisions of paragraph (a) would resultin more frequent calibration, ifnecessary. MSHA notes that under theprevious standard, there was no writtenmaintenance program required nor wererecords required. MSHA believes thatexperience under both the previous andexisting standards demonstrates that,with the addition of paragraph (e),maintenance and calibration isappropriately addressed in the final ruleand safety is not reduced.

Several commenters agreed with theproposal for a ‘‘trained’’ person tomaintain air quality detectors andmeasurement devices. Thesecommenters suggested that the trainedperson be defined as a persondesignated by the operator who hasreceived training through experience inmaintenance of the instrument, has beentrained by an experienced person, orone who has received training by orthrough the instrument manufacturer.MSHA has not adopted this suggestionsince the operator should have someflexibility as to the mode of training.The requirement that the personperforming the maintenance must betrained is intended to mean that theperson be capable of doing the requiredmaintenance, not that they receive aspecific course of instruction in what todo.

Commenters suggested thatmaintenance and calibrationrequirements should parallel thoseproposed under § 75.342 for machine-mounted methane monitors. Theysuggested that, because the detectorsand monitors perform similar functions,the requirements should be similar. Thefinal rule does not adopt this suggestion.The methane monitoring instrumentsunder this standard and those governedby § 75.342 are subject to differentmining conditions. For example,machine-mounted monitors must becalibrated and maintained underground,on the equipment on which they areinstalled and on working sections. Thiscalibration must also be scheduledwithin production timetables. Handhelddetectors and measurement devices,however, are removed from the mineand are maintained and calibrated insurface environments. Calibration andmaintenance of handheld detectors isusually done during shifts when theinstruments are rotated out of service.Thus machine-mounted monitors arecalibrated and maintained under morestrenuous conditions than handhelddetectors.

One commenter suggested thatwritten records of all maintenance andcalibration should be required. Thecommenter further suggested that: Eachoperator submit a written maintenanceprogram to MSHA for approval andprovide a copy to the miner’srepresentative; the written programspecify training to be provided; recordsbe completed by the person performingmaintenance and be countersigned bythe mine foreman within 24 hours; andthat records be maintained for one yearand be made available to MSHA and therepresentative of the miners. Theseadditional requirements were notincluded in the proposal and are notadopted in the final rule. Therequirements contained in the final ruleadequately address and areappropriately related to the concernsrelative to maintenance, calibration,permissibility, and the generalcondition of air quality detectors andmeasurement devices.

Section 75.321 Air QualityThe primary function of a mine

ventilation system is twofold, to removehazardous gases such as methane, andto provide miners with an respirableenvironment in areas where they arerequired to work or travel. As discussedin the introductory section of thispreamble, § 75.321 of the existingstandard was stayed by the UnitedStates Court of Appeals for the Districtof Columbia Circuit as it pertains tobleeder entries. The final rule, in


§ 75.321, addresses acceptable levels ofoxygen and carbon dioxide in areas ofa mine, including areas of a bleederentry, where persons are required towork or travel.

Paragraph (a)(1) continues a basic airquality requirement that has been inplace since 1970 that air in areas wherepersons work or travel contain at least19.5 percent oxygen and not more than0.5 percent carbon dioxide, and thevolume and velocity of the air currentin these areas be sufficient to dilute,render harmless, and carry awayflammable, explosive, noxious, andharmful gases, dusts, smoke, and fumes.Paragraph (a)(2) applies the samerequirement for oxygen, 19.5 percent,for the air in areas of bleeder entries andworked-out areas where persons work ortravel. The final rule does not requirethe carbon dioxide level of 0.5 percentto be applied to bleeder entries andworked-out areas. Rather paragraph(a)(2) requires that the carbon dioxidelevels in the air in bleeder entries andworked-out areas where persons work ortravel not exceed 0.5 percent time-weighted average (TWA) and 3.0percent short-term exposure limit(STEL).

MSHA interpreted former § 75.301 torequire at least 19.5 percent oxygen andno greater than 0.5 percent carbondioxide in bleeder systems wherepersons work or travel. It was MSHA’sintent that existing § 75.321 wouldnecessitate compliance with these levelswhere persons would be exposed inbleeder entries and in worked-out areas.However, the application of thisprovision to bleeders and worked-outareas was stayed by the United StatesCourt of Appeals pending the outcomeof litigation addressing thepromulgation of the existing rule.MSHA continues to believe thatproviding necessary air quality isessential to protect miners andexaminers whenever they work or travelin bleeder entries and worked-out areas.Therefore, the final rule includes a newprovision specifying that the air inbleeder entries and worked-out areaswhere persons work or travel contain atleast 19.5 percent oxygen, and thatcarbon dioxide not exceed 0.5 percentTWA and 3.0 percent STEL. A TWA isthe time-weighted average concentrationfor a normal 8-hour workday and a 40-hour workweek. A STEL is themaximum time-weighted averageconcentration to which miners can beexposed for a continuous period of upto 15 minutes. Commenters noted anerror in the preamble to the proposalwith respect to the time an individualcan be exposed to concentrationsbetween the TWA and the STEL. MSHA

intends to apply TWA and STEL levelsin a manner consistent with the AirQuality rulemaking. The levels forcarbon dioxide in the final rule for areaswhere persons work or travel in bleederentries and worked-out areas areidentical to the levels contained inMSHA’s proposed Air Quality standardsfor coal and metal and nonmetal minesand the 1992 Threshold Limit Values(TLVs) as specified by the AmericanConference of Governmental IndustrialHygienists (ACGIH).

Some commenters suggested thatother changes be included in the finalrule. First, they recommended that thepermissible minimum oxygen level forbleeders and worked-out areas belowered from 19.5 percent to 18 percent.Second, they suggested that therequirements that apply to bleeders andworked-out areas be expanded toinclude airways associated withbleederless mining areas. The rationalegiven for this second recommendationwas that the conditions in these airwaysare similar to bleeders. In light of theongoing Air Quality rulemaking, MSHAis not at this time clarifying existing AirQuality standards except those forworked-out areas and bleeder entries.

Commenters for the most part agreedwith the change relative to carbondioxide although one commenterindicated that there was no need for anystandard. Bleeder entries and worked-out areas are required to be traveled orevaluated at least weekly. Generally,this is done by a person traveling alonewho is often required to be in thebleeder entries or worked-out areas foran extended period. The purpose of thisstandard is to protect miners, not toregulate air quality where persons arenot exposed. Therefore, if examinationsare performed remotely or if personsmaking the examination can otherwiseremain in air that meets therequirements of the standard, oxygenand carbon dioxide levels at bleederconnectors and bleeder evaluationpoints would not have to meet theconcentrations required by the finalrule.

According to the National Institute forOccupational Safety and Health(NIOSH) of the U.S. Department ofHealth and Human Services (NIOSHRespirator Decision Logic, May 1987),19.5 percent oxygen provides anadequate amount of oxygen for mostwork assignments and incorporates asafety factor. Also according to NIOSH,the safety factor is needed becauseoxygen-deficient atmospheres offer littlewarning of danger. In the NIOSHpublication, ‘‘A Guide to Safety inConfined Spaces,’’ (page 4), a chart ispresented that indicates that 19.5

percent oxygen is the minimum level forsafe entry into an area, and that at alevel of 16 percent, judgement andbreathing are impaired. The AmericanNational Standards Institute (ANSI), inANSI Z88.2–1992, ‘‘American NationalStandard for Respiratory Protection’’recognizes that at 16 percent oxygenthere is an impairment in the ability tothink and pay attention, and a reductionin coordination. ANSI recognizes that at19 percent oxygen there are someadverse physiological effects.

The need for regulating the oxygenlevel where persons work or travel inbleeder entries is illustrated by twomining accidents. One of theseaccidents resulted in the death of a mineexaminer and the second resulted in thenear death of two individuals, one ofwhom was a mine examiner. Mineexaminers are, through training andexperience, the individuals best able toidentify the hazards associated withirrespirable atmospheres. The firstaccident occurred at the Arclar Mine inEquality, Illinois in 1989. Prior toimplementation of the existing standard,a mine examiner entered a worked-outarea that was posted with a danger signand was asphyxiated. Under the existingregulation, ventilation or sealing of thisarea, rather than posting, would berequired. Because the area was notsealed, the existing regulation wouldrequire the area to be examined duringthe weekly examination. The final rulewould require that the route of travel forthe examiner contain at least 19.5percent oxygen. Had the final rule beenin place when the examiner entered theworked-out area, the accident may havebeen avoided.

The second accident, although not ina bleeder entry or worked-out area, isillustrative of what can happen whenindividuals, including mine examiners,are subjected to oxygen deficient air. In1983 at the Bird No. 3 Mine inRiverside, Pennsylvania, an assistantmine foreman, a certified person,entered the mine for the purpose ofconducting an examination. Aftertraveling approximately 1100 feet, theexaminer became dizzy, noticed that hisflame safety lamp had extinguished andwithdrew approximately 200 feet wherehe sat down and apparently becameunconscious. A second individual uponentering the area in search of theexaminer also became dizzy but wasable to withdraw to a location that wasnot oxygen deficient. When the mineexaminer regained consciousness, hiscap lamp battery had discharged and hetraveled in total darkness until heencountered a mine rescue team. Airsamples collected in the area where themine examiner first became dizzy


indicated an oxygen level of about 16.8percent, while other samples collectednearby indicated oxygen concentrationsof nearly 20 percent.

Because mine examiners are requiredto work or travel in areas where oxygen-deficient air could occur withoutwarning, and they normally travel andwork alone, there must be a requirementthat provides them the protectionnecessary for the performance of theirduties under these conditions. It isimportant that the level for oxygen beestablished above that identified asresulting in impaired judgementbecause it is essential that individualstraveling in these areas remain highlyalert. The hazards that can exist inbleeder entries and worked-out areasinclude elevated methane levels, poorfooting, loose and unstable roof, andwater accumulations. For this reason,the final rule adopts a minimum levelof oxygen of 19.5 percent asrecommended by NIOSH.

MSHA is also concerned with theeffects of other gases often found inbleeder entries. Section 75.322 of theexisting regulation limits theconcentration of noxious or poisonousgases to the current (1971) TLV’s asadopted and applied by the ACGIH.Section 75.322 specifically excludescarbon dioxide since it is covered by§ 75.321. However, so the mining publicwill clearly understand the applicationof the regulation, the final ruleestablishes a separate standard forcarbon dioxide levels for areas wherepersons work or travel in bleeder entriesand worked-out areas. The levels set bythe final rule, 0.5 percent TWA and 3.0percent STEL, when considered inconjunction with the requirements of§ 75.322 and the requirement foroxygen, will provide persons working ortraveling in these areas with a safe andhealthful working environment. MSHArecognizes that the effects of carbondioxide are both chronic and acute and,therefore, sets both a TWA and a STEL.NIOSH, in recommending a standard forcarbon dioxide, also recognized this andrecommended a similar approach. TheNIOSH recommendation, made in aCriteria Document published in 1976,proposed a TWA concentration of 1.0percent and a ceiling value of 3.0percent not to exceed 10 minutes. Inmaking this recommendation, NIOSHrecognized that there are additive stresseffects of increased carbon dioxideconcentrations and exercise. As supportfor this, the NIOSH document citesresearch that showed that healthy,trained subjects exposed to 2.8 to 5.2percent carbon dioxide at maximumexercise levels experienced respiratorydifficulty, impaired vision, severe

headache, and mental confusion; threesubjects collapsed.

During rulemaking on the proposedair quality standard, NIOSHrecommended a 0.5 percent TWA and a3.0 percent STEL. NIOSH made asimilar recommendation to theOccupational Safety and HealthAdministration during that Agency’spermissible exposure limit rulemaking.Given the work environment in bleederentries and worked-out areas, asdescribed earlier, MSHA believes thatthe regulatory approach to bleeders andworked-out areas provided by the finalrule is necessary and appropriate. Inaddition to examiners, other miners maybe required to work in the bleederentries and worked-out areas,performing duties such as installing roofsupport, pumping water, recoveringmaterials or adjusting ventilation. Thelevels established in the final rulewould provide these miners with thenecessary protection.

Section 75.323 Actions for ExcessiveMethane

Section 75.323 establishes the actionsthat must be taken when methanereaches certain levels. Methane is themost dangerous gas encountered byminers working underground. When thelevel of methane reaches 5.0 percent itis explosive. Section 75.323 generallyestablishes action levels below thislower explosive limit to permitappropriate actions to be taken by mineoperators in order to prevent anexplosion.

The final rule adopts the proposal for§ 75.323. In doing so, it revisesparagraphs (b)(1)(ii), (c)(1), and (d)(2)(i)of the existing standard. The ruleclarifies that corrective actions atspecified methane levels must be taken‘‘at once’’ and provides that actions forexcessive methane include areas wheremechanized mining equipment is beinginstalled or removed. MSHA believesthat final rule § 75.323 increases theprotection afforded by the existingstandard.

Initially, the need for clarification wasraised during informational meetingsand subsequent discussions afterpublication of the existing rule. Asdiscussed below, the final rule retainsthe language of the proposal which isidentical to the wording of the previousstandard.

Some commenters indicated thatdelays in remedial actions to reducemethane were being experienced atsome mines. These commentersattributed delays to the deletion of thephrase ‘‘at once’’ in the existingstandard. These commenters alsosuggested that the phrase ‘‘at once’’

conveys the proper sense of urgency tocorrect the condition. Other commentersstated that the addition of the phrase ‘‘atonce’’ does nothing to improve health orsafety. MSHA has included the phrasein the final rule for clarity.

Methane poses a significant hazard tominers when it is permitted toaccumulate without corrective actionbeing taken quickly. MSHA has alwaysintended that corrective changes bemade at once. The final rule revisesparagraphs (b)(1)(ii), (c)(1) and (d)(2)(i)to require that these changes be made‘‘at once,’’ the phrase used in former§§ 75.308 and 75.309.

Some commenters stated that theproposal, if literally enforced, wouldnecessitate changes to be made beforethe cause or source of the increase inmethane can be investigated. Othercommenters stated that approvals mustbe obtained for many ventilationchanges and that some changes requireextended periods of time to complete.Operators may take those actionsnecessary to abate imminent dangers orhazardous conditions, or to safeguardpersons and equipment. A part of thisaction would be a determination of thecause of the problem. MSHA knows ofno case where an operator has beenprohibited from a necessary correctionfor a methane problem pending a planapproval. However, in cases whereintentional changes are made whichcould materially affect the safety andhealth of miners, approval is requiredbefore resumption of normal work if thechanges affect the information approvedin the mine ventilation plan. MSHArecognizes that some ventilationchanges take time to accomplish andinterprets the phrase ‘‘at once’’ asmeaning that the work of making thenecessary change to reduce methanelevels begins immediately.

One commenter questioned how thephrase ‘‘at once’’ would apply to amethane feeder which is encountereddespite an appropriate and well thoughtout ventilation change. MSHArecognizes that methane feeders may beencountered unexpectedly. As long as amine operators takes action as requiredby the standard, they will be incompliance.

One commenter suggested that someMSHA personnel were improperlyinterpreting methane excursions above1.0 percent to be violations of thestandard. The commenter seemed tosuggest the regulations should providethat the actions specified in § 75.323 forexcessive methane do not apply toconcentrations detected on machine-mounted methane monitors. Othercommenters indicated that the standardrequires unnecessary ventilation


changes in response to instantaneousincreases caused by excessive methaneliberation. MSHA recognizes thatinstantaneous methane monitorreadings for machine mounted monitorsmay occasionally reach or exceed 1.0percent. Usually, these are short-livedand the monitor reading quickly fallsbelow 1.0 percent, even before themachine operator can react. However,consistent monitor readings of 1.0percent or more indicate a problem andshould cause appropriate changes andadjustments. Repeated short durationincreases above 1.0 per cent should alsobe cause for concern and maynecessitate changes or adjustments toventilation.

With respect to paragraphs (b)(1),(b)(2), and (c)(1) some commentersstated that the mere presence ofmethane does not constitute a violationof a mandatory health and safetystandard. MSHA agrees. In this context,one commenter suggested replacing theword ‘‘present’’ with ‘‘detected.’’ Thecommenter continued that an operatorcannot possibly correct a methaneproblem until it has been detected, thatthe rule should reflect realisticexpectations, and that the current term‘‘present’’ is meaningless. MSHA agreesthat a methane problem cannot becorrected unless it has been detectedand that the mere presence of methanedoes not constitute a violation. Only thefailure to properly respond once beingmade aware of the presence of methanein excess of allowable levels is aviolation. The standard requires that anoperator properly conduct anexamination; and if methane over 1.0percent or 1.5 percent is found, asapplicable, corrective action must betaken at once.

When 1.0 percent or more methane ispresent in a working place, an intake aircourse, or an area where mechanizedmining equipment is being installed orremoved, paragraph (b)(1)(i) of the finalrule requires all electrical, diesel, andbattery- powered equipment in theaffected working place, intake aircourse, or other area, except forintrinsically safe AMS, to bedeenergized or shut off. Deenergizing orshutting off of this equipment protectsminers by preventing this equipmentfrom providing ignition sources.

One commenter suggested that non-intrinsically safe AMS equipmentshould be permitted to run underbattery power when 1.0 percent or moremethane is encountered. Thecommenter stated that the benefitderived through the system’s operationoutweighs the hazard of the non-intrinsically safe system. Thecommenter continued that since the

batteries will deplete quickly, littlehazard would result, or in thealternative, each battery outstationcould be monitored for methane andautomatically trip at some set methanelevel. The final rule does not includethis suggestion. Where excessivemethane concentrations necessitate thatpower be deenergized, information fromcontinued operation of the non-intrinsically safe system would notoutweigh the potential ignition hazard.To permit operation of a non-intrinsically safe system in areas knownto contain excessive levels of methanewould be a departure from accepted,effective, and long standing safetypractice.

Several commenters objected to therequirement in paragraph (b)(1)(iii) thatprohibits any work in the affected areauntil the methane is reduced to lessthan 1.0 percent. Commentersquestioned whether the standard wouldprohibit an operator from taking steps toreduce the methane. The language mustbe given a reasonable interpretation andshould be considered in context of thepreceding requirement in paragraph (ii)that ‘‘changes or adjustments shall bemade at once * * * ’’

These requirements are virtuallyidentical to those found in the previousstandard which was in effect for over 20years. MSHA is unaware of any instancewhere an operator was prohibited fromcorrecting methane problems by such anapplication of the standard.

Some commenters suggested adding aphrase to paragraph (b)(1)(iii) to read,‘‘No work other than removal of theaccumulation shall be permitted * * * ’’Similarly, MSHA believes that thesuggested change is unnecessary andhas not adopted it. MSHA experienceindicates that the rule is wellunderstood and has been properlyapplied.

Other commenters thought that thestandard, as proposed, would causehasty, ill-advised changes to be madeand would prohibit an investigation intothe cause or source of the methaneproblem which could result in phased-in corrections. MSHA agrees thatoperators should seek long termsolutions and should fully investigatethe cause or source of methaneaccumulations. Investigation and longterm corrections are not prohibited bythe rule. However, the final rule doesrequire that certain actions beundertaken at once to correct the shortterm or acute safety hazards resultingfrom accumulations of methane.

If 1.5 percent or more of methane ispresent in a working place, an intake aircourse, or an area where mechanizedmining equipment is being installed or

removed, paragraph (b)(2) of the finalrule requires persons to be withdrawnfrom the affected area. The presence ofmethane in these areas can pose asignificant risk to miners and thereforetheir withdrawal from the affected areais essential to their safety. Paragraph(b)(2) also requires that all electricpower to equipment in affected areas bedisconnected at the power source. Thisprevents accidental energization ofequipment and removes power fromcables and circuits which may also beignition sources. No other work ispermitted in the affected area until theconcentration of methane is less than1.0 percent. A conforming change is alsomade to paragraph (b)(2) by adding‘‘mechanized’’ before mining equipmentfor consistency with other provisions ofthe rule.

Comments were received whichobjected to the (b)(2)(ii) requirementthat except for intrinsically safe AMS,electrically powered equipment in theaffected area shall be disconnected atthe power source. Some commenterssuggested that this equipment should besimply ‘‘deenergized.’’ Thesecommenters stated that there was noneed to disconnect the power source,that this could require belt drives,pumps, etc. to be physicallydisconnected where permanentconnections have been made, whichcould result in a major unnecessaryoperation. MSHA has not adopted thissuggested revision. MSHA issuesnumerous citations and orders fordamaged power cables, trailing cables,and splices where the conductors arebadly damaged or exposed. Each ofthese citations and orders represents thepresence of a potential ignition source.Power cables would remain energizedunder these conditions as would be thecase if the commenters’ suggestion wereadopted.

There are several aspects of § 75.323which were not proposed for revision,but for which comments were received.Comments were received relative to the1.0 percent action level in intake aircourses. Commenters contended thatCongress established an immutablemethane limitation of 0.25 percent inintakes. Commenters stated that becauseCongress had expressly limited intakespassing openings to abandoned areas to0.25 percent methane, that implicitly,all intakes were limited to 0.25 percentmethane. However, the commenter thensuggested adopting an intake actionlevel for methane of 0.5 percent. MSHAnotes that the methane levels were notproposed for revision and are not beingrevised under the final rule. Thecommenters, however, should refer to adiscussion of this issue included in the


preamble to the existing rule dated May15, 1992.

If 1.5 percent or more methane ispresent in return air, paragraph (d)(2)(i)would require changes or adjustmentsbe made ‘‘at once’’ to the ventilationsystem to reduce the concentration ofmethane. Because of the hazardspresented by accumulations of methane,MSHA believes that changes oradjustments should be madeimmediately and be made independentof the mine ventilation plan in theinterest of safety. MSHA recognizes thatsome changes take time to complete. Ifoperators begin ‘‘at once’’ to make thenecessary changes and adjustments,they will be in compliance with thestandard.

MSHA received comments relative to§ 75.323 which, although were outsidethe scope of the rulemaking,demonstrate an incorrect understandingof the existing rule. The limitations onmethane content and the associatedactions required when excessivemethane is encountered are importantcomponents of a safety program toprotect underground miners. Therefore,several of these comments will beaddressed so that the miningcommunity will better understand thesestandards.

First, one commenter objected to theexisting requirements in § 75.323(d).The commenter incorrectly stated thatparagraph (d) permits normal operationswith 1.5 percent methane in workingplaces. Methane limits in workingplaces and intake air courses is limitedby § 75.323(b). Paragraph (b) specifiesactions if 1.0 percent methane ispresent, and withdrawal if 1.5 percent ispresent. Similarly, § 75.323(c) limitsmethane between the last working placeon a working section and where thatsplit of air meets another split of air to1.0 percent and requires withdrawal at1.5 percent. Paragraph (d) modifies therequirement for that portion of thereturn split outby the section loadingpoint and has no effect on methaneeither in working places or between thelast working place and the point in thereturn opposite the loading point.

One commenter indicated apreference for the language used in aprevious MSHA regulation, § 75.308–1.The previous standard restricted thechanges or adjustments to increasing thequantity or improving the distributionof air in the affected working place to anextent sufficient to reduce and maintainthe methane to less than 1.0 percent.The existing rule establishes aperformance standard that allows forseveral methods of compliance. Oneacceptable method of compliance is tolimit the rate of production of coal to

permit the existing ventilation system tomaintain the level of methane below 1.0percent. In all cases, however,increasing the quantity or distribution ofair continues to be an accepted meansof reducing methane levels. No safetybenefit would be derived fromdisallowing reduced coal extractionrates as a means of maintaining methanelevels under 1.0 percent.

The final rule retains the language ofproposed §§ 75.323(b)(1)(i),75.323(b)(1)(iii), and 75.323 (b)(2)(i) and(b)(2)(ii) which is identical to thewording of the existing standards. Anin-depth discussion of the reproposal ofprovisions concerning the installationand removal of mechanized miningequipment is presented in the GeneralDiscussion section of this preamble.

Section 75.324 Intentional Changes inthe Ventilation System

This section addresses theprecautions that must be taken when asignificant change is made to theventilation system. MSHA did notpropose any change to existing § 75.324and is not making any revisions in thefinal rule.

Questions had been raised concerningthe language, ‘‘materially affect thesafety or health of persons in the mine’’that appears in the existing standard.The phrase is important in that itidentifies those ventilation changes thatrequire approval of the MSHA districtmanager under § 75.370(c). MSHAregards it as impractical to follow a‘‘cookbook’’ approach to identifyingwhat will or will not require approval.Each particular circumstance is to bereviewed by the operator on its ownmerits. To illustrate the Agency’sexpectations, the following is a list ofsome examples of what MSHAconsiders intentional changes thatwould materially affect the safety orhealth of miners. These examples arenot meant to include all possibilities,but are meant to provide some generalguidance: adding a new shaft; bringinga new fan on line; changing thedirection of air in an air course;changing the direction of air in a bleedersystem; shutting down one fan in amultiple fan system; starting a newoperating section with ventilatingquantities redistributed from othersections of the mine; changing entriesfrom intakes to returns and vice versa;and any change that affects theinformation required by § 75.371, Mineventilation plan; contents.

Comments were specifically solicitedon issues raised in the preamblediscussion to the proposal. In response,written comments were received fromone commenter. These comments were

reinforced by several speakers at thepublic hearings. Other commentersindirectly referred to § 75.324 and statedthat the phrase, ‘‘materially affect thesafety or health of persons in the mine’’is accepted and understood by themining community.

One commenter suggested that theperson designated by the operator tosupervise ventilation changes should bea certified person that is knowledgeableof the mine’s ventilation system. Theresults of changes to a complexventilation system are not always easyto predict, and for that reason cautionmust be used when making significantchanges to one air split or several airsplits. The balance of splits can beaffected and may result in air reversals,dead air spaces, or insufficient air flowin critical areas. For this reason, suchchanges must be evaluated by a certifiedperson examining the affected areas todetermine that the areas are safe beforeproduction is resumed. Therefore, theAgency believes that it is to be anunnecessary burden to also haveventilation changes supervised by acertified person. Thus, the suggestion ofthe commenter has not been adopted inthe final rule.

This commenter also suggested thatthe provisions of § 75.324 should applyto all intentional changes which alterthe air current in any section or area ofthe mine by 10 percent or more, or by9,000 cfm or more, whichever is lessand that such change be considered toaffect the entire mine. The commenterrecommended the miners’representative be afforded the right toaccompany the certified person toevaluate the effects of the ventilationchange and that a preshift examinationof the mine be conducted to assure thatthe mine is safe before electric power isrestored.

The commenter also suggested that arecord be maintained of all ventilationchanges to include the names of allpersons involved with the change, thedate and time of the change, and resultsand locations of air quality and quantitymeasurements taken both before andafter the change. The commenter statedthat the record should be made in anapproved book within 24 hours of thechange and that the record should besigned and countersigned. Finally, thecommenter recommended that the mineventilation map should be updatedimmediately after the ventilation changeis made and that within 24 hours of thechange, the updated map should bemade available to the miners’representative and a copy sent to thedistrict manager. Section 75.370(c)requires that any change to theventilation system that alters the main


air current or any split of the main aircurrent in a manner that couldmaterially affect the safety or health ofthe miners, or any change to theinformation required in § 75.371 shallbe provided to and approved by thedistrict manager before implementation.The final rule requires that thisinformation be provided to the miners’representative at least 5 days beforesubmittal to the district manager (See§ 75.370 for full discussion). MSHAbelieves that this provision providesnecessary protection for miners.

One commenter stated that thestandard is reactive and that MSHAroutinely cites mine operators after amethane explosion or ignition. MSHAbelieves that the standard is designed toassure that operators are proactive anddevelop plans that prevent hazardousconditions. The Agency anticipates thatwith the clarification provided throughthis rulemaking, operators will obtainMSHA approval prior to makingintentional ventilation changes thatmaterially affect the safety and health ofminers, thereby preventing potentiallyhazardous conditions. When questionsarise as to whether an anticipatedchange requires prior approval, MSHAis available to provide guidance as towhether approval is necessary.

Section 75.325 Air Quantity

The quantity of air in cubic feet perminute (cfm) is an important measure ofunderground coal mine ventilation. It isessential for miners’ health and safetythat each working face be ventilated bya sufficient quantity of air to dilute,render harmless, and carry awayflammable and harmful dusts and gasesproduced during mining. Aninsufficient quantity of air at a workingface could permit methane toaccumulate and lead to an explosion.Section 75.325 generally establishes thequantities of air that must be providedand the locations underground wherethese quantities must be provided.

Section 75.325(d) requires that areaswhere mechanized mining equipment isbeing installed or removed be ventilatedand that the minimum quantity of airand the ventilation controls necessary toprovide these quantities be specified inthe approved mine ventilation plan. Thefinal rule adds the word ‘‘minimum’’ tothe phrase, ‘‘quantity of air’’ thatappears in the existing standard and theproposal. The existing standard wasreproposed without change. An in-depth discussion of the reproposal ofprovisions concerning the installationand removal of mechanized miningequipment is presented in the GeneralDiscussion section of this preamble.

Only a few comments were receivedthat were specific to paragraph (d). Onecommenter discussing § 75.371(r)suggested that the quantity of airrequired by § 75.325(d) to be specifiedin the plan should represent the‘‘minimum’’ quantity to be providedand that the location specified shouldbe identified as typical so as to give themine the flexibility to adapt toconditions. This comment is consistentwith MSHA’s intent for the proposaland helps to clarify it. Therefore, theword ‘‘minimum’’ has been insertedinto the final rule in both § 75.371(r)and paragraph (d) of § 75.325.Obviously, mine operators can have airquantities which exceed the minimumspecified in the mine ventilation plan.MSHA agrees conceptually with acomment that the ventilation schemeshown in the plan should berepresentative of the method ofventilation to be used. However, MSHAdoes not adopt this comment becausethe plan must also be specific enough sothat the operator, the miners, therepresentative of miners, and MSHA areassured that the areas are beingadequately ventilated.

Other commenters suggested that thetotal quantity of air to be delivered to alongwall needs to be specified in themine ventilation plan. In support of thesuggestion the commenter stated thatthe inclusion of the word ‘‘total’’recognizes that some mines may use beltair at the set up or tear down phasewhile some intake air may be divertedto ventilate bleeders, battery chargers orcompressors and, therefore, the totalquantity of air being delivered to thelongwall face should be the figure withwhich MSHA is concerned. Thecommenter stated further that therecommendation recognizes thatconditions vary greatly from mine tomine, coal seam to coal seam, even fromone longwall panel to the next panel ofthe same mine. The commenter addedthat while a specified amount of air canbe delivered to a recovery face, andpressure can be placed on the gob, it isimpossible to guarantee a specifiedvolume or velocity of air at the recoverypoint.

MSHA agrees that the total airquantity provided to a recovery face isof importance; however, the distributionof this air is also important. The volumeof air being delivered to the longwallface during equipment removal isimportant because of the types ofactivities that occur (e.g. cutting andwelding and the operation in some casesof considerable numbers of dieselpowered vehicles) and the fact that it isalong the face that the majority ofminers work and where an ignition

hazard exists. It is important to knowexactly how areas where mechanizedequipment is being installed or removedwill be ventilated. Therefore, thissuggestion has not been included andthe rule.

Commenters were concerned aboutthe ventilation of a longwall face priorto the first gob fall. This type of concernshould be handled through the mineventilation plan. Paragraph (d) onlydeals with areas were mechanizedmining equipment is being installed orremoved and not where mining is inprogress.

Section 75.330 Face VentilationControl Devices

The final rule adds a new paragraph(c) adopting the proposal language. Thenew paragraph (c) requires that whenline brattice or any other faceventilation control device is damaged toan extent that ventilation of the workingface is inadequate, production activitiesin the working place are required tocease until necessary repairs are madeand adequate ventilation is restored.MSHA notes that before issuing acitation for a violation of this provision,an inspector would normally beexpected to measure the air quantity todetermine whether adequate ventilationis being maintained.

Some commenters considered theproposed regulation redundant sinceoperators must already maintainminimum air quantities at the face,thereby making repairs necessary tomaintain the required quantity. Faceventilation controls are a critical featureof reliable ventilation. As such,maintaining these controls in goodcondition and making repairs necessaryto restore ventilation is sound safetypractice. To do less invites increasedrisk of a methane ignition and elevatedrespirable dust. Also on a practical levelmost miners on a working section donot have a means of measuring airquantities. However, miners candetermine when ventilation controls aredamaged appreciably and are likely toadversely affect the air quantity.

One commenter indicated that entireworking sections might be shut down torepair a ventilation control at any oneface with no corresponding safetybenefit. The final rule provides that‘‘production activities in the workingplace shall cease’’ until adequateventilation is restored. Unless elevatedmethane levels or some other problemexisted, the entire section would not beshut down for repair of a ventilationcontrol.

Some commenters asserted thatcontrols may be slightly damaged whilestill maintaining quantities in excess of


the requirements at the face. Similarly,commenters worried that numerouscitations would be issued based solelyon the appearance of the controls, eventhough the minimum required face airquantities are exceeded. Thesecommenters stated that the only reliableindicator is an air measurement.

MSHA agrees that the only preciseindicator of air quantity is ameasurement. Accordingly, MSHAanticipates that noncompliancedecisions will be based on airmeasurements which show ‘‘ventilationof the working place is inadequate.’’However, ventilation controls which arein poor condition are likely to cue aninspector to conduct an airmeasurement.

Other commenters generallyexpressed the view that therequirements of § 75.330, evenconsidering the proposed revision, areinadequate to fully address the issue offace ventilation. According to thesecommenters, additional requirementsare needed, including: properinstallation and maintenance criteria forface ventilation control devices,requirements for providing devicescontinuously from the last opencrosscut to the working face, immediaterepair of these devices if damaged by afall or otherwise, providing sufficientspace between the line curtain and therib and maintaining the area free ofobstructions, and minimizing leakagewhile providing installations whichpermit traffic to pass without adverselyaffecting ventilation. Further, thecommenters asserted that onlycumulatively can the desired result beobtained through these requirementsand that additional requirements wouldempower individual miners to takecorrective actions when needed.

Each of these suggestions is adesirable ventilation practice whichMSHA supports. However, the final ruleis not intended to set detailed standardsfor the installation of ventilation controldevices. Instead, the rule addressesminimum requirements for face airquantities and requires the faceventilation system used to deliver thesequantities to be maintained.

Some commenters indicated aconcern about so-called ‘‘deep-cut’’mining wherein continuous miners, byremote control, develop cuts from 25 to60 feet inby permanent roof support.Commenters questioned the adequacy offace ventilation where ventilationcontrols may be 30 to 50 feet from theface. Specifically, questions were raisedabout: whether adequate ventilationactually reaches the face in ‘‘deep cuts’’to dilute methane; whether morefrequent air measurements are needed;

whether methane checks arerepresentative of face concentrations;maximum feasible cut depth andventilation device distance; respirabledust in ‘‘deep cuts;’’ propermaintenance of ventilation controldevices; how ventilation is maintainedafter the continuous miner is withdrawnfrom the cut; roof bolter ventilation; anddifferences between scrubber systemsand sprayfan systems. Anothercommenter noted that historically mostroof fall fatalities have occurred within25 feet of the face. This commenterasserted that the deep-cut miningsystem helps to resolve this problemand reduce exposure. The commentercontinues that to prohibit any variationfrom the 10 foot line curtain distancerequirement would adversely affectsafety of the miners working in the area.

MSHA agrees that each of these issuesis important. The appropriate vehicle toaddress these specific concerns is themine ventilation plan required byexisting § 75.370. The mine ventilationplan provides the necessary latitude toaddress the diversity of miningconditions found throughout thecountry. Details of each system must beshown in the plan and must be specificto the conditions at each mine wheresuch a system is employed. Also,MSHA’s review and approval of mineplans includes an onsite investigation toevaluate the system and to assess theadequacy of the specified planparameters. In addition, inspectorsroutinely evaluate the suitability of themine ventilation plan during regularmine inspections.

The commenter’s concerns aboutmethane checks in ‘‘deep cuts’’ isaddressed by the final rule§ 75.362(d)(2) which requires thatmethane tests be made ‘‘at the face.’’This new requirement will assure thatmeasurements are taken at the locationwhere the hazard is most likely to occur.Testimony received at the publicrulemaking hearings indicated thattechnology exists in the form ofextendable probes that can be used totake these measurements, withoutputting miners at additional risk fromfall of ground.

Section 75.332 Working Sections andWorking Places

Working sections and working placesare the areas of a coal mine with thegreatest amount of activity and thelargest concentration of workers. Theyare the location of the greatest numberof potential ignition sources. Theytherefore harbor the greatest risk ofaccidents such as methane ignitions andexplosions and equipment fires. Section75.332 addresses the ways these areas

are ventilated to reduce the likelihoodof an accident on one section impactinganother section, with deadlyconsequences. Generally, § 75.332provides that each of these areas mustbe ventilated with a separate split offresh air that has not been used toventilate another working area or anarea where mining has ceased if thisarea cannot be examined. Whenventilated in this manner, the productsfrom a fire on one section will notcontaminate another section andmethane in worked-out areas will not becarried to working sections by theventilating air stream.

The final rule provides that eachworking section and each area wheremechanized mining equipment is beinginstalled or removed, shall be ventilatedby a separate split of intake air directedby overcasts, undercasts or otherpermanent ventilation controls. Thefinal rule adopts the language ofproposed § 75.332(a)(1), which isidentical to existing § 75.332(a)(1). Anin-depth discussion of the reproposal ofprovisions concerning the installationand removal of mechanized miningequipment is presented in the GeneralDiscussion section of this preamble.

Several commenters responded to§ 75.332(a)(1). Some commenterssuggested that the standard be revised topermit the installation of mechanizedmining equipment in either the returnor intake air courses of working sectionsprovided the air had not been used toventilate any worked-out areas, areaswhere pillars have been recovered, orbleeder systems. The commentersmaintained that prohibiting theinstallation of longwall equipment onthe same split of air as a developing unitdelays the installation of a miningsystem. The commenters furtherobserved that this mining equipmentconsists mainly of steel conveyorsections and roof supports that containa 95 percent water-based hydraulic fluidwhich does not burn. Therefore,according to these commenters,longwall mining equipment can safelybe installed on the intake side of anactive mining unit and, withmonitoring, in the return air course ofan active mining unit.

The safety benefits of using separatesplits of air to provide ventilation arewell established. A primary benefit ofsuch a provision is to protect workersdown-wind from being put at risk byevents up-wind from their location.Among the most serious of these risksis miners being overcome by theproducts of combustion or an explosion.

In Miner’s Circular 50, ‘‘Explosionsand Fires in Bituminous-Coal Mines’’published by the Bureau of Mines in


1954, the authors state that when airtravels a long path through a mine, itgradually becomes depleted of oxygenand may become so contaminated withother gases that it no longer is healthful,or it may accumulate enough explosivegas to present an explosion hazard. Theauthors go on to state that when the airis divided into several splits, eachtraveling a short path, better air can befurnished to each group of persons inthe mine. Further, if a local explosion orfire should occur, the poisonous gasesevolved may be confined to one sectionand the force of the explosion and thegases may kill all the persons in thatparticular section but may not affectother sections of the mine. According tothe authors, when a mine is ventilatedby a continuous current of air, theminers on the return side of anexplosion or fire probably will be killedor overcome by the poisonous gases andthat judicious splitting of the air is asafeguard against this eventuality.

Similarly, Stefanko states in the 1973edition of the Society of MiningEngineers (SME) Engineering Handbookthat splitting the air is recognized asbeing necessary for safety and presentsonly minimal power cost.

The commenters implied that becauselongwall mining equipment is largelynoncombustible, this danger isminimized for workers down-wind onan active mining section. This reasoningoverlooks the fact, however, that theinstallation of a longwall is labor-intensive, involving cutting and weldingin the presence of methane and coal, aswell as machinery operating under load.These conditions add contaminants tothe ventilating current, and increase thepossibility of a fire or explosion.Likewise, a longwall being installed onthe return side of an active miningsection would expose the miners doingthe installation to the dust and gases,and the results of a fire or explosion,from the section. Even with monitoring,miners would be put at risk as theiropportunities for escape would belimited. For these reasons, the final ruledoes not adopt the commenters’’suggestion.

One commenter also suggested that‘‘approved ventilation controls’’ berequired instead of specifying thatovercasts, undercasts or otherpermanent ventilation controls be usedto direct intake air. The commenterexplained that this would allowoperators the flexibility of submittingplans that allow the use of temporarycontrols in some instances.

Temporary controls to split air are notas reliable as permanent controls. Thefirst explosion at the Scotia Mine in1976 which killed 15 miners, was due

in part to the improper use of atemporary ventilation control where apermanent control (i.e., an overcast)should have been used. More recently,the explosion that occurred during theset up of a longwall at the Golden EagleMine in 1991 which injured 11 minersinvolved the removal of two permanentventilation controls and the replacementof these controls with temporarycontrols. As these and other accidentsillustrate, the ventilation controls thatdeliver air to working areas are vitallyimportant to miners’’ safety. Therefore,the final rule requires that these controlsbe permanent in nature and nottemporary.

Another commenter indicated that theuse of temporary controls would lowerworker exposure to hazards by notrequiring repeated handling ofpermanent control materials which canbe heavy. Proper handling practices andmodern materials can reduce the risk ofinjuries associated with handlingconstruction materials. MSHA considersthese risks lower than the dangers ofusing temporary controls in lieu ofpermanent controls.

Section 75.333 Ventilation Controls

The primary means for directing airfrom the outside, through the mineopenings, to the working areas and backto the surface is through the use ofventilation controls: either permanentcontrols, such as stoppings (walls),overcasts or undercasts (air bridges),and doors, or temporary controls, suchas line brattice (curtains). Permanentventilation controls are designed forlong term use while temporary controlsare intended for use on a short termbasis. In general, § 75.333 specifieswhere each type of control can be usedand how each permanent control is tobe constructed. It is essential thatventilation controls be correctlyconstructed, maintained, and properlylocated to provide ventilation toworking sections and other areas whereit is needed to dilute methane,respirable coal mine dust and othercontaminants, and provide miners witha safe and healthful work environment.

The final rule revises paragraphs (a),(b)(1), (b)(3), (b)(4) and (e)(1) of existing§ 75.333, and adds a new paragraph (h).Revisions to paragraphs (a) and (e)(1)address the durability of stoppings,while the revisions to (b)(1), (b)(3) and(b)(4) address ventilation controlsrequired when continuous haulagesystems are used. New paragraph (h)requires all permanent ventilationcontrols, including seals, to bemaintained to serve the purpose forwhich they were built.

The use of continuous haulagesystems, particularly in low seam coalmines, is becoming more common. Thefinal rule specifically addressescontinuous haulage systems inparagraphs (b)(1), (b)(3) and (b)(4) of therule and clarifies where temporarycontrols are an acceptable means ofventilation control when these systemsare used. Continuous haulage systemsutilize mobile bridge conveyors orsimilar mechanisms to transport coaldirectly from a continuous miningmachine to a low profile belt. As thecontinuous mining machine moves fromplace to place, the continuous haulagesystem slides back and forth along a lowprofile conveyor belt using a ‘‘dolly’’ orother travel mechanism. The low profileconveyor belt then transports the coal tothe section conveyor belt.

The existing rule permits the use oftemporary ventilation controls in lieu ofpermanent ventilation controls toseparate continuous face haulagesystems from return, intake, andprimary escapeway entries in roomsdeveloped 600 feet or less from thecenterline of the entry from which therooms were developed. This practice isconsistent with longstanding MSHApolicy, which recognizes that theserooms are used for a short duration andthe minimum air quantity must bemaintained regardless of the controlsused.

Existing paragraph (b)(1) allowstemporary controls to separate intakeand return air courses in rooms driven600 feet or less from the centerline ofthe entry from which the room wasdeveloped. The final rule adds toexisting paragraph (b)(1) the proposedlanguage clarifying that the use oftemporary controls in these rooms isalso acceptable when continuoushaulage systems are used. This changeresponds to commenters who point outthat the rooms in which the continuoushaulage systems are installed arecontinuously attended by the operatorsof the system and an immediateresponse to any safety related problemwith the system or the ventilationcontrols would be expected.Commenters also noted that two or threerooms are often concurrently developedusing a continuous haulage system andthe life of the actively developing roomsis often less than three days. As a resultof this short life, mining in these roomsis often completed before constructionof permanent controls is finished. Also,access to the continuous haulage systemis required through crosscuts formaintenance and operation of thesystem.

Under paragraphs (b)(3) and (b)(4) theproposal would have required belt and


intake separation to the outby travelpoint of the dolly and belt and primaryescapeway separation to the inby mosttravel point. Commenters indicatedconfusion because of the distinctionbetween intake and primary escapewayseparation and believed that conflictswould exist. Commenters also suggestedthat the language proposed to addressthe use of temporary ventilationcontrols for continuous haulage systemswas confusing and contradictory. Thefinal rule revises the requirements ofproposed paragraphs (b)(3) and (b)(4) torespond to these comments.

Paragraph (b)(3) of the final ruleretains the requirement that permanentcontrols be provided to separate beltconveyor haulageways from intake aircourses when the air in the intake aircourse is used to provide air to activeworking places. The final rule alsoretains the proposed provision thatwhen continuous haulage systems areused in rooms less than 600 feet fromthe centerline of the entry from whichthe rooms were developed, temporarystoppings or other temporary ventilationcontrols may be built and maintained toprovide the required separation.

Commenters stated that newtechnology may result in continuoushaulage systems with the outby point oftravel of the dolly extendingconsiderably beyond the 600 feetdistance. The commenters noted thatsuch an extended length of temporarycontrols could result in unanticipatedadverse consequences for the ventilationsystem, and suggested that a maximumdistance of 300 feet outby the inby pointof travel of the dolly be established forthe use of temporary ventilationcontrols. MSHA agrees that extensiveuse of temporary ventilation controlscan create problems, includingexcessive leakage and the possible shortcircuiting of air. The final rule,therefore, limits the distance thattemporary controls may be used toseparate continuous haulage systemsfrom intake air courses, including theprimary escapeway. The final rulepermits temporary controls to be usedfrom the point of deepest penetration ofthe conveyor belt entry to the mostoutby point of travel of the dolly or 600feet, whichever distance is the less. Asa result, 600 feet is the maximum lineardistance of entry in which temporarycontrols may be used for separation ofair courses. The 600 feet would bemeasured as a straight-line distancefrom the point of deepest penetration inthe conveyor belt haulage entry. Thisapproach comports with the 600 footlimit for the use of temporary stoppingsin rooms and allows a reasonable use oftemporary ventilation controls with

continuous haulage systems, whilepreserving the integrity of theventilation system. At present, MSHAwould expect that the most outby pointof travel of the dolly would govern sinceMSHA is not aware of any continuoushaulage systems which travel more than600 feet outby the point of deepestpenetration.

Paragraph (b)(4) of the final rulecontinues to require permanentstoppings or other permanentventilation control devices to separatethe primary escapeway from the beltand trolley haulage entries, as requiredby § 75.380(g). Commenters suggestedthat for the purposes of § 75.380(g), thedefinition of loading point in proposedparagraph (b)(4) be revised to be theoutby point of travel of the dolly asopposed to the inby point of travel. Thefinal rule adopts this suggestion andrequires separation by permanentstoppings to be maintained to the outbypoint of travel of the dolly or 600 feetfrom the point of deepest penetration,whichever distance is less, to separatethe haulage entry from the primaryescapeway. The provisions of§ 75.380(g) continue to allow the districtmanager to require a greater or lesserdistance for this separation.

In response to questions aboutacceptable construction methods andmaterials for permanent ventilationcontrols (excluding seals) MSHAproposed eliminating the definition of‘‘durable’’ in paragraph (a) and tomodify paragraph (e)(1). The proposalwould have required these controls tobe constructed in a manner and ofmaterials that result in a constructionthat has been tested and shown to havea minimum strength of 39 pounds persquare foot as tested under ASTM E72–80 Section 12—Transverse Load-Specimen Vertical, load only (ASTME72–80). The 8-inch hollow-coreconcrete block stopping with mortaredjoints, to which all other constructionswere tied under the definition ofdurable in the existing standard, hasbeen tested and shown to have aminimum strength of 39 pounds persquare foot.

MSHA received numerous commentsquestioning the validity of the ASTME72–80 test for determiningacceptability of underground ventilationcontrols. Commenters questioned theappropriateness of a strengthrequirement of 39 pounds per squarefoot and the relevance of this value tothe in-mine conditions. After review,MSHA continues to believe that use ofthe ASTM E72–80 test to determine thatthe relative strength of a ventilationcontrol construction is appropriate andthe final rule retains this standard.

However, MSHA sees merit in some ofthe suggestions made by commenters.Commenters suggested that someconstructions can not be testedaccording to the ASTM test, someconstructions that are widely used incoal mines do not meet the 39 poundper square foot threshold, and theASTM test can only be run at a limitednumber of locations nationwide.

After reviewing all of the commentsreceived and based on experience withvarious construction methods andmaterials used for permanentventilation controls since the inceptionof the Mine Act, the final rulerecognizes traditionally acceptedconstruction methods for permanentventilation controls, and retains theASTM test for new materials andmethods. Controls made with newmaterials or methods must becomparable in strength to controls madewith traditionally accepted materials ormethods.

Since the inception of the Mine Act,a number of traditionally acceptedconstruction methods have performedadequately and have served theirintended function of separating aircourses. These traditionally acceptedconstruction methods are: 8-inch and 6-inch concrete blocks (both hollow-coreand solid) with mortared joints; 8-inchand 6-inch concrete blocks dry-stackedand coated on both sides with a strengthenhancing sealant suitable for dry-stacked stoppings; 8-inch and 6-inchconcrete blocks dry-stacked and coatedon the high pressure side with astrength enhancing sealant suitable fordry-stacked stoppings; steel stoppings(minimum 20-gauge) with seams sealedusing manufacturer’s recommendedtape and with the tape and perimeter ofthe metal stopping coated with asuitable mine sealant; and lightweightincombustible cementatious masonryblocks coated on the joints andperimeter with a strength enhancingsealant suitable for dry-stackedstoppings. In addition, 4-inch concreteblocks may be used in the aboveapplications in seam heights less than48 inches. Tongue and groove 4-inchconcrete blocks coated on both sideswith a strength enhancing sealantsuitable for dry-stacked stoppings maybe used in coal seams of any height. Thesealants referred to in this paragraphwould be applied in the thicknessrecommended by the manufacturer.MSHA maintains a list of sealantswhich may be used for the aboveapplications. This list is available ateach MSHA District Office. The finalrule would continue to permit thesetraditionally accepted construction


methods to be acceptable for theconstruction of ventilation controls.

For new construction methods ormaterials other than those used for thetraditionally accepted constructionsidentified above, the final rule requiresthat the strength be equal to or greaterthan the traditionally accepted in-minecontrols. Tests may be performed underASTM E72–80 Section 12—TransverseLoad-Specimen Vertical, load only, orthe operator may conduct comparativein-mine tests. In-mine tests must bedesigned to demonstrate thecomparative strength of the proposedconstruction and a traditionallyaccepted in-mine control.

As with the existing rule, the finalrule would require, in paragraph(e)(1)(ii), that all overcasts, undercasts,shaft partitions, permanent stoppings,and regulators, installed after November15, 1992, be constructed ofnoncombustible material. Also, like theexisting standard, the final rule listsmaterials that would be suitable forthese controls. The final rule would alsocontinue to prohibit ventilation controlsinstalled after November 15, 1992, frombeing constructed of aluminum.

Paragraph (h) of the proposal wouldhave required that all permanentventilation controls, including seals, bemaintained to serve the purpose forwhich they were built. The final ruleretains proposed paragraph (h) with onerevision. One commenter stated that theparagraph should require all ventilationcontrols, including temporary controls,to be maintained to serve the purposefor which they were built. Given theimportance of temporary controlsdevices in providing for adequateventilation, the final rule requires allventilation controls, both permanentand temporary, including all doors andseals, to be maintained to serve thepurpose for which they were built. Thisstandard applies to all ventilationcontrols, regardless of the constructiondate.

Relative to seal maintenance, MSHAdoes not intend that the maintenancerequirement be applied to seals locatedwithin another sealed area.Additionally, the rule does not apply toseals which have become consumedwithin a gob area which is ventilatedand evaluated in a manner approved inthe mine ventilation plan.

One commenter raised severalquestions concerning what MSHAwould consider to be an acceptabletemporary stopping. MSHA has notdefined the term ‘‘temporary ventilationcontrol’’ in the rule. The commenterstated that, in the preamble to theproposal, MSHA refers to ‘‘properlyconstructed’’ temporary stoppings but

does not include a standard forconstruction or installation andmaintenance of temporary stoppings.The commenter adds that temporaryventilation controls are a source ofpotential leakage and are oftensusceptible to damage from roof and ribfalls and from mobile equipment. Thecommenter also refers to severalaccidents where failure to maintainpermanent or temporary ventilationcontrols was a critical factor in theaccident.

MSHA agrees that to properly directthe flow of air and provide for adequateface ventilation, temporary controls, aswell as all permanent ventilationcontrols, must be installed andmaintained in an adequate manner tocontrol leakage. MSHA has accepted astemporary controls, check curtains orother flame- resistant material approvedby MSHA that are constructed andinstalled in such a manner to minimizeleakage. As required by paragraph (h) ofthis section of the final rule, thesecontrols must be maintained to serve thepurpose for which they were built.

Section 75.334 Worked-Out Areas andAreas Where Pillars Are BeingRecovered

Worked-out areas, areas where coalextraction has been completed, can posedeadly hazards to miners, including anexplosive methane accumulation,irrespirable atmosphere, and thepossibility of fire from spontaneouscombustion. Section 75.334 establishesthe requirements for ventilation of theseareas to mitigate these hazards. Ingeneral, § 75.334 requires that followingmining, these areas are to be sealed orventilated. Section 75.334 also specifiesthe requirements for evaluating theeffectiveness of the ventilation ofworked-out areas so operators candetermine that the ventilation system isfunctioning as intended.

The final rule revises paragraph (e) ofthe existing § 75.334. Existing paragraph(e) requires that each mining system bedesigned so that worked-out areas canbe sealed. The final rule adds toparagraph (e) the proposed requirementthat the location and sequence ofconstruction of proposed seals bespecified in the approved mineventilation plan. Improper location andsequencing of seal construction canhave a dangerous effect on mine airquality and ventilation. As the properlocation and sequence of construction ofseals is a mine-by-mine determination,the mine ventilation plan provides themost workable mechanism by which toassure proper air quality and ventilationof the mine.

Several commenters objected toincluding seal construction sequence aspart of the information to be submittedfor approval in the mine ventilationplan. Their rationale was that miningconditions change and could result in achange in the sequence of sealconstruction. The construction mightthen be delayed while approval for thechange is obtained. These commenterssuggested that in some cases, delays inseal construction could result in ahazard to miners. Other commentersstated that the sequence of constructionof seals is more appropriately and moreeasily shown on the mine ventilationmap required by § 75.372. Anothercommenter stated that the sequence ofconstruction should be subject toapproval because the placement of sealsif improperly installed can causeadverse effects on the ventilation systemand gob gases. MSHA is sensitive to theconcern that a delay in approval couldresult in a hazard to miners and, asexplained in the preamble discussion of§ 75.370, if a delay in seal constructionwould result in a hazard to miners thereview and approval of the plan can beexpedited.

MSHA agrees with the commenterthat the location and sequence of sealconstruction may be more easily, that is,more clearly shown on the mine maprequired by § 75.372 than in the writtentext of the plan submitted under§ 75.371. The existing standard permitsappropriate information required under§ 75.371 to be shown on the maprequired by § 75.372. The effect is thatthe information both appears on theventilation map and in the ventilationplan and is subject to approval. Thediscussion of § 75.371(bb) furtheraddresses this point.

Spontaneous combustion is theprocess through which coal or othermaterials self heat by the absorption ofoxygen. Paragraph (f) of § 75.334addresses mines with a demonstratedhistory of spontaneous combustion andthose located in coal seams determinedto be susceptible to spontaneouscombustion. Paragraph (f) requires thatthe approved mine ventilation plan forthese mines specify the measures thatwill be used to detect methane, carbonmonoxide, and oxygen concentrationsduring and after pillar recovery, and inworked-out areas where no pillars havebeen recovered; the actions that will betaken to protect miners from the hazardsof spontaneous combustion; and, if ableeder system will not be used, themethods that will be used to controlspontaneous combustion,accumulations of methane-air mixtures,and other gases, dusts, and fumes in theworked-out area.


Through meetings with varioussegments of the mining community,MSHA became aware of a concern thatparagraph (f) of existing § 75.334 mayhave been promulgated without thepublic being provided the opportunityto adequately comment. AlthoughMSHA believes that existing paragraph(f) was promulgated properly, theAgency reproposed paragraph (f) withwording identical to that used inexisting § 75.334. The purpose of thereproposal was to assure MSHAreceived and considered all pertinentcomments.

Several commenters to the existingrule suggested that bleeder systemsshould not be required for all mines.These commenters stated that in somemines the practice of ventilatingworked-out areas increases the risk ofspontaneous combustion by supplyingoxygen to combustion-prone materialsin these areas. They also requested thatthe final rule promulgated in 1992include provisions to addressspontaneous combustion. MSHAacknowledged the need to reduce theflow of oxygen to areas where there isa likelihood of spontaneous combustion,and included in the 1992 rulerequirements for mine ventilation plansto address spontaneous combustion inmines with a demonstrated history ofthis hazard or mines that are located incoal seams determined to be susceptibleto spontaneous combustion.

Experience gained throughapplication of the existing standard hasdemonstrated that a limited number ofmines have experienced spontaneouscombustion problems. Studies by theBureau of Mines have identified thevolatile properties of coal seams andhave determined that certain seams aresusceptible to spontaneous combustion.The final rule is directed to mines inthese seams.

MSHA is not suggesting that all coalmines will meet the test to showsusceptibility to spontaneouscombustion. A demonstrated history orthe determination of susceptibility tospontaneous combustion is aprerequisite to the applicability ofparagraph (f). While it is true that allcoal oxidizes when exposed to air, thisfact is not sufficient to make thedetermination that a coal seam issusceptible to spontaneous combustion.MSHA would expect that absent ademonstrated history of spontaneouscombustion in a mine, an operatorwould provide the necessary data todemonstrate that the mine is susceptibleto spontaneous combustion so that theprovisions of paragraph (f) shouldapply. A number of methods are used to

determine the self heating tendency ofa coal.

However, MSHA is also mindful thatsome mines that have a spontaneouscombustion problem may be unable toreduce the oxygen content to asufficiently low level to mitigatespontaneous combustion. For thesemines, a bleederless system may not beappropriate. To illustrate, it is wellknown that the oxygen level in a gobvaries depending on the location wherethe measurement is made. For example,the periphery of a gob normally willhave higher oxygen levels than theinterior of the gob. The oxygen level inthe interior of the gob is critical whendealing with spontaneous combustion.If conditions are such that the oxygencontent in critical areas within a gobcannot be reduced below that necessaryfor a methane ignition to occur, ableeder system may provide the mostsafety. MSHA specifically solicitedcomment on this subject; however, nonewas received.

Under paragraph (f)(1), the approvedventilation plans for mines that have orare susceptible to spontaneouscombustion must specify measures todetect methane, carbon monoxide, andoxygen concentrations in worked-outareas. These measures must be takenduring and after pillar recovery and inworked-out areas where no pillars havebeen recovered. The purpose of thesemeasures is to determine if worked-outareas will be ventilated or sealed. If themethane concentration or other hazardsin the worked-out area cannot becontrolled while the mine is limitingairflow to avoid spontaneouscombustion, it may be necessary to sealor to ventilate the worked-out area usinga bleeder system. These measures alsohelp to determine the extent to whichthe worked-out areas can be ventilatedwithout increasing the spontaneouscombustion hazard.

Under the provisions of paragraph(f)(2) the operator is required to specifyin the mine ventilation plan the actionsthat will be taken to protect miners fromthe hazards of spontaneous combustion.Protections from the hazards ofspontaneous combustion might include:Additional continuous monitoring offire gases at strategic locationsunderground, increased air samplecollection and analysis, trending of aircontaminant data, increasedexaminations, and changes to the mineventilation system such asredistribution of air or pressurebalancing. This requirement would betriggered if the mine has a demonstratedhistory of spontaneous combustion, or,if an evaluation of the susceptibility ofthe coal seam to spontaneous

combustion leads to a mine operatordetermination that a bleeder systemshould not be used.

One commenter stated that this rule isunnecessary because only a limitednumber of mines actually have ademonstrated spontaneous combustionproblem. The commenter suggested thatthe petition for modification (variance)process should be used to address thisissue, which would allow minersrepresentatives to participate. The finalrule does not adopt this approach. Tothe extent practicable, an objective ofthis rulemaking is to reduce the need forexceptions and paperwork. In this case,the existing mine ventilation planprocess provides a ready-mademechanism for establishing theprecautions necessary, on a mine-by-mine basis, to protect miners from thehazards of spontaneous combustion in atimely manner. In addition, under thefinal rule, miners representatives areafforded input into the mine ventilationplan.

Another commenter stated thatparagraph (f) should be directed more tothe detection and control ofspontaneous combustion and not solelyat its prevention. The commenteroffered examples of detection andcontrol techniques that could be used.

MSHA agrees that spontaneouscombustion prevention, detection andcontrol are all important when dealingwith spontaneous combustion. The finalrule recognizes, however, that whileprevention is the goal, instances ofspontaneous combustion will occur.

Another commenter stated that thepreamble to the proposal was notcorrect in that it implied a need to limitairflow to avoid spontaneouscombustion. The commenter states that,to avoid spontaneous combustion,miners must create a near-zero pressuredifferential across most areas ofconcern. MSHA agrees that creating a‘‘near-zero pressure differential’’ willhave the desired effect of limiting theairflow. In a paper entitled‘‘Examination of Bleederless VentilationPractices for Spontaneous CombustionControl in U. S. Coal Mines’’ presentedat the 7th U.S. Mine VentilationSymposium in June 1995, the authorsreport that their study revealed thatrestricting airflow into mined-out areasis recognized world-wide as aspontaneous combustion controlmeasure and that when designing ableederless ventilation system criticalattention must be given to mine layout,seal construction, methane drainage,regulations, monitoring, and emergencyprocedures. In discussing the subject ofair leakage, Koenning in a paper entitled‘‘Spontaneous Combustion in Coal


Mines’’ presented at the 4th U.S. MineVentilation Symposium in June 1989,identified air leakage as the most oftencited cause of spontaneous combustion.In both of these papers, the authorsemphasize the need to properly designa bleederless ventilation system toreduce the likelihood of spontaneouscombustion and achieve the level ofworker safety desired. MSHA agreeswith these authors that a bleederlessventilation system must be designed toencompass all of the factors identified.It was suggested by one commenter thatmeasurement of carbon dioxide shouldbe included in the requirements ofparagraph (f). In discussing the gasesrequired to be measured (methane,oxygen, and carbon monoxide), thecommenter stated that these gases alonewill not aid in the detection ofspontaneous combustion in its incipientor developed stage. The commentersuggested that miners be required tomonitor for carbon dioxide because, inthe opinion of the commenter, the trendin the ratio CO/CO2 is the only viablepredictor.

MSHA sees merit in the measurementof carbon dioxide as well as otherproducts of combustion to assist in thedetection of spontaneous combustion.However, the ratio CO/CO2 is not theonly viable predictor of spontaneouscombustion. One researcher suggestedthat carbon monoxide production is theearliest, detectable effect of spontaneousheating. Others have suggested,following a series of tests, that four gasratios clearly indicated the developmentof thermal runaway, but only the CO2¥>O2 ratio gave an early warning of theheating in the coalbed.

As can be seen, a number of methodsof predicting the onset of spontaneouscombustion have been suggested. Whileparagraph (f)(1) requires only themeasurement of methane, oxygen, andcarbon monoxide, MSHA would notdiscourage operators fromincorporating, as part of the mineventilation plan, any or all of thesemethods as well as other appropriatemethods to aid in the early detection ofspontaneous combustion.

Section 75.340 Underground ElectricalInstallations

Electrical installations can provide anignition source for methane and canrepresent a serious fire hazardunderground. Typical electricalinstallations are battery chargingstations, substations, rectifiers andcertain water pumps. Section 75.340requires that these installations beventilated and protected against fire.These installations must also be housedin noncombustible structures or areas or

protected with fire suppressionssystems, and be ventilated or monitoredto protect miners working down streamfrom the products of combustion.

MSHA proposed to revise paragraph(a) of existing § 75.340 to clarify thestandard and to add requirementsconcerning alarms and sensors. Thefinal rule adopts the language in theproposal with one modification. Itreplaces the word ‘‘located’’ with theword ‘‘housed.’’

Existing 75.340(a) requires thatcertain underground electricalequipment be either located in anoncombustible structure or area orequipped with a fire suppressionsystem. Section 75.340 (a) also requiresthat the equipment be ventilated byintake air, and lists alternatives ways todo so in paragraphs (a)(1),(a)(2), and(a)(3). The final rule adds language toparagraph (a)(3), the alternative whichestablishes an acceptable means formonitoring the underground electricalinstallations using sensors other than a§ 75.351 atmospheric monitoringsystem.

MSHA sought in the proposal toclarify the application of existing§ 75.340(a)(3). Paragraph (a)(3) of theexisting rule provides for the activationof doors upon the presence of certainindications of a possible fire. Theparagraph was appropriate for enclosedstructures or areas; but questions atinformational meetings challenged itsapplicability to the alternative where afire suppression system was usedwithout an enclosure. To address thequestions, the proposal placed therequirements for noncombustiblestructures or areas and for firesuppression systems into separateparagraphs. MSHA proposed that one ofthe alternatives for ventilating withintake air (monitoring the undergroundelectrical installations using sensorsother than a § 75.351 atmosphericmonitoring system) was acceptable onlyif the equipment was located in anoncombustible structure or area andnot acceptable if only a fire suppressionsystem was used. This revisioneliminates the confusion that existedwith the existing rule. It should benoted that if an operator elects to locatethis equipment in a noncombustiblestructure or area, the operator would notbe precluded from also installing a firesuppression system.

One commenter questioned the reasonfor separating fire suppression andnoncombustible structures, noting thatthere was no need for the distinction inthe rule. In objecting to the proposal, thecommenter stated that there should beseveral cumulative layers of protection,including both fireproof enclosures and

fire suppression systems. Thecommenter includes several examples offires involving compressors to illustratethis point. MSHA has addressedconcerns relative to compressor fires inthe final rule section dealing withcompressors, § 75.344. Other examplescited by the commenter includedexplosions caused by mobile equipmentand a fire that occurred on a powercenter located at the working section.The instances cited by the commenterare not relevant to § 75.340. Thecommenter argued that fire suppressionsystems have not worked and uses thecompressor fires previously mentionedto illustrate the point. MSHA notes thatthere are numerous instances where thesystems have worked. However, in thevast majority of these cases there is nodocumentation because there is norequirement for reporting fires that areextinguished within 30 minutes.

The final rule in paragraph (a)(1)(iii)revises existing paragraph (a)(3) of§ 75.340 by adding 2 requirements. Itadds a requirement that a visual andaudible alarm be provided oninstallations if the (a)(1)(iii) alternativeis selected. Also, when operating underthis alternative, monitoring of intake airthat ventilates battery charging stationsmust be done with sensors not affectedby hydrogen.

Some commenters noted theiragreement with these proposed changes.Noting that no single system is failsafe,one commenter suggested that all therequirements of § 75.340 be combinedand made applicable in all cases. Therequirements would include;noncombustible structures, firesuppression, ventilation directly to thereturn, additional communications,continuous AMS monitoring for carbonmonoxide, methane, and hydrogen,along with automatic closing doors andtemperature protection. Afterconsideration of the comments and theunderlying rationale, MSHA concludesthat to require that the alternatives beapplied cumulatively in every casewould be infeasible or impractical. Inaddition, MSHA does not believe thatthese overly restrictive requirements arenecessary in all circumstances.

Paragraph (a)(1)(iii) addresseselectrical installations that are equippedwith doors that automatically closewhen sensor readings reach certainlevels. One of these action levels is alevel for the optical density of smoke. In§ 75.340 (a)(1)(iii)(B) of the proposal andthe preamble discussion on page 26371,MSHA refers to the optical density ofsmoke of 0.05 per meter to characterizethe sensitivity of smoke detectors. Asdiscussed in MSHA’s opening statementto the ventilation rulemaking hearings,


the value used for the optical density ofsmoke is based on information providedfrom the Bureau of Mines. MSHApointed out that based on commentsreceived from the Bureau of Mines, thisnumber is incorrect and should bedivided by 2.303 to conform to theinternationally accepted term of opticaldensity. No commenter took issue withthis point. MSHA has made thecorrection in the final rule. Onecommenter suggested that opticaldensities be increased and based on anambient to account for background dust.In contrast, another commentersuggested that the specified opticaldensity should be reduced by half.MSHA has found insufficientjustification to adopt either of thesesuggestions and believes that thespecified 0.05, corrected to 0.022 basedon comments from the Bureau of Mines,is the appropriate level for opticaldensity used in § 75.340. Existing§ 75.351 Atmospheric monitoringsystem (AMS), uses a level for opticaldensity of smoke of 0.05 per meter.MSHA recognizes that the level in§ 75.351 should also be corrected.MSHA intends to correct the level foroptical density used in § 75.351 in afuture rulemaking. In the meantime,MSHA will use an optical density of0.022 per meter for purposes of § 75.340.

The visual and audible alarm requiredin paragraph (a)(1)(iii) must be situatedso that it can be seen or heard bypersons traveling in the intake entryimmediately adjacent to the installation.It was suggested to MSHA that theseelectrical installations may besusceptible to fire and the fire could goundetected. The visual and audiblealarms would provide additional safetyat these installations by alerting minersin the area.

One commenter suggested that analternative should be added to carbonmonoxide or smoke detection. Thesuggested alternative would be to permitanother means that would be approvedby the district manager. This suggestionhas not been adopted since both carbonmonoxide monitoring and smokedetection have been shown to beeffective and reliable and can be used.

One commenter stated that batterychargers located on working sections donot present the same hazards as thoselocated outby, along the intake. Thecommenter suggested that chargerslocated on working sections should beexempted from § 75.340. MSHAdisagrees. MSHA believes that batterychargers present the same safety hazardsassociated with other electricalequipment plus the charging of batteriesresults in the liberation of hydrogen.There is a demonstrated history of fires

caused by battery chargers. Therequirements are necessary to safelyoperate chargers, regardless of thelocation of the charger.

One commenter suggested that allwater pumps should be exempted from§ 75.340 because fire history is limited.The standard already exempts pumpsthat have limited fire hazard potential inparagraphs (b)(2) through (b)(6). Pumpsoutside of the listed categories dopresent hazards. As an example, a 200horsepower pump exploded at a mine inVirginia after an extended period ofbeing overheated. An example of apump posing a limited hazard is anemulsion pump located at or near thesection that is moved as the sectionadvances or retreats. Emulsion pumpsare considered for the purpose of§ 75.340 to be water pumps.

Also, one commenter called attentionto MSHA’s omission of the word ‘‘or’’ intwo places in § 75.340, UndergroundElectrical Installations. MSHA agreesthat the omission was inadvertent andso stated in its opening statement at theventilation hearings. In § 75.340, theword ‘‘or’’ has been inserted betweenparagraphs (a)(1) (i) and (ii) dealing withalternative ventilation requirements fornoncombustible structures or areas andbetween paragraphs (a)(1)(iii) (A) and(B) setting out criteria that would governthe activation of automatic closingdoors.

Another commenter suggested thatthe signal from the visual and audiblealarms required by existing paragraph(a)(3) should be sent to a surfacelocation at the mine rather than beinglocated outside the installation. Thecommenter supported the suggestion byindicating that a quicker responsewould thus be provided since the alarmwould be immediately noticed. In orderto achieve an effective level of safety,MSHA has provided in paragraph(a)(1)(iii) that the visual and audiblealarm be located outside of and on theintake side of the enclosure. Thislocation will permit persons traveling inthe intake entry immediately adjacent tothe installation to see or hear the alarm.Paragraph (a)(2) allows the use of analternative system using an AMS whichwould provide an alarm at the surfaceof the mine.

Finally, one commenter objected tothe use of the word ‘‘located’’ in thephrase ‘‘located in noncombustiblestructures or areas’’. The commenterargued that MSHA should use the word‘‘housed’’ and that the use of the word‘‘located’’ actually reduces theprotection intended by Congress. MSHAdoes not agree with that interpretationand maintains that in the context inwhich the word is used there is no

meaningful distinction between the twowords. However, because the wordsuggested by the commenter will notreduce safety and may add to the clarityof the rule for some readers, it has beenadopted in the final rule.

Section 75.342 Methane MonitorsMethane monitors are a critical link in

the safety protections designed toprevent mine explosions. Mounted onmining equipment which works directlyin the face, these instruments providethe first warning that gas is beingliberated in potentially dangerousquantities. Methane monitors are reliedupon to shut down mining equipmentautomatically when gas concentrationsreach 2 percent. The continuedoperation of mining equipment underthese conditions can lead to a spark andcatastrophic explosion.

The final rule revises paragraph (a)(4)which addresses maintenance andcalibration of methane monitors that arerequired on underground miningequipment to provide a warning toequipment operators when the methaneconcentrations nears dangerous levels.Methane monitors also automaticallydeenergize the equipment whenmethane approaches the explosive rangeor if the monitor is not operatingproperly. The rule requires that trainedpersons perform maintenance andcalibration of the methane monitors atleast every 31 days and requires thatcalibration records be maintained. Thefinal rule does not adopt the proposalwhich would have required that awritten maintenance program beavailable for inspection.

Some commenters expressed the viewthat the proposed revisions wereunnecessary and recommended thatthey be deleted from the final rule.Other commenters supported theproposed revisions and urged MSHA toadopt additional requirements as well.

Paragraph (a)(4) of the final rulerequires that calibration andmaintenance of the monitors beperformed by persons properly trainedin maintenance, calibration, andpermissibility of the methane monitors.One commenter expressed the view thatno change was needed to the existingrule. However, the rulemaking recordalso contains a number of examples inwhich poorly maintained or improperlyrepaired methane monitors have beenfound during the investigations ofmethane related accidents.

The final rule in paragraph (a)(4)(ii)requires that each operator maintain arecord of all calibration tests of methanemonitors. As with other recordkeepingrequirements under the final rule,records must be maintained in a secure


book that is not susceptible to alteration,or may be kept electronically in acomputer system so as to be secure andnot susceptible to alteration. Somecommenters recommended that a recordbe kept of all maintenance performed ona methane monitor, urging that a recordis necessary to prove the maintenance isdone. MSHA believes that the revisionscontained in the final rule, together withthe existing requirements, will assure anappropriate level of maintenancewithout the need for additional recordsof maintenance.

Some commenters expressed concernover the security of computer-basedrecords, and offered examples ofbreaches of security in the banking andnational security fields. Others,however, advocated the use ofcomputers for the storage and retrievalof records as being highly accurate,requiring less storage space andfacilitating data retrieval. MSHA agreesthat security of required records isimportant. It is also MSHA’s objective tomake the final rule requirements forcompilation and storage of recordspractical and in concert with modernmethods. To this end, the final rulerequires that the record of maintenanceand calibration of methane monitors bemaintained in secure books that are notsusceptible to alteration, and alsopermits these records to be maintainedelectronically in a computer system soas to be secure and not susceptible toalteration. The calibration record willaid operators in tracking calibrationactivity and will serve as a check toassure that calibrations are beingconducted at least once every 31 days.The record will also be reviewed byauthorized representatives of theSecretary and miners’ representatives todetermine that calibrations are beingconducted as required.

Paragraph (a)(4)(iii) of the final rulerequires that operators retain the recordof calibration tests for 1 year from thedate of the test. Records are to bemaintained at a surface location at themine and made available for inspectionby authorized representatives of theSecretary and the representative ofminers. A discussion of commentsconcerning the use of computers tomaintain records can be found in theGeneral Discussion of this preamble.

Several commenters suggested thatequipment not operated in the face areaalso be equipped with methanemonitors. Commenters noted accidentswhich have occurred when thisnonpermissible equipment has ignitedmethane in outby areas. Commentersalso asserted that equipment used forthe withdrawal of personnel during fanstoppages would be safer if methane

monitors were provided. An opposingcomment indicated that an expansion ofthe methane monitor coverage was notnecessary since methane is rarelyassociated with outby areas. Because ofthe response time of methane monitors,and considering the speed at whichmost outby equipment normallyoperates, it is unlikely that a monitorwould prevent a machine from enteringa body of methane if such aconcentration were encountered. MSHAbelieves that methane monitors aresuitable and effective in face areaswhere coal is being cut, mined, orloaded. However, MSHA does notbelieve that an expansion of coverage toinclude all nonpermissible equipment iswarranted.

A number of commentersrecommended that methane monitorsshould be calibrated at least every 7days rather than at least every 31 daysas provided by the existing standard.One commenter suggested dailycalibration. Commenters noted thatmethane monitors lose sensitivity andthat response time increases withmonitor age and after exposures toelevated methane concentrations. Theexisting requirement for calibration ofmethane monitors at least every 31 daysparallels the recommendations ofseveral manufacturers. The 31 dayrequirement establishes a maximumtime interval between calibrations.However, the final rule also requires theoperator to maintain methane monitorsin permissible and proper operatingcondition. Thus, under unusualcircumstances of use, it is possible thatweekly or even more frequentcalibration may be necessary to complywith the standard.

Comment was also receivedrecommending an additionalrequirement that calibration records becountersigned by the MaintenanceSupervisor or Chief Electrician at themine. The final rule does not adopt thisrecommendation. The purpose of thecalibration record required under thefinal rule is not the same as otherrecords where countersigning isrequired by the final rule.Countersigning requirements aredirected at informing upper minemanagement of hazardous conditionswhich require their attention. While thecalibration record has the potential toassist mine management in identifyingequipment problems, its main functionis to assist operators in assuring thattimely calibration is occurring.

The proposal would have requiredthat operators adopt a writtenmaintenance program for methanemonitors. Commenters pointed out thatthe existing standard already requires

all permissible equipment, includingmethane monitors, to be maintained inpermissible condition. MSHA agrees.

Section 75.344 CompressorsSection 75.344 deals with the use of

air compressors underground. Asdiscussed in the introductory section ofthis preamble, MSHA stayed § 75.344(a)because of a concern over a possibleoverheating or fire hazard. Improperlyused or maintained air compressors canpresent a significant risk of fireunderground. MSHA determined thatthe cause of the 1984 fire at the WilbergMine that claimed the lives of 27 minerswas an improperly maintainedcompressor. In general, § 75.344requires that most compressors beoperated only while attended or locatedin a noncombustible structure or areathat is monitored for temperature andcarbon monoxide or smoke; have a firesuppression system; and, automaticallyshut down in the event of a fire.

The final rule revises the existing§ 75.344, including the stayed paragraph(a), and supersedes interim § 75.345.The final rule recognizes that in somecases compliance with the existing rulecould result in heat buildup when acompressor is located in anoncombustible structure or area. Toaddress this possible hazard the finalrule provides an option. A compressorwould be acceptable when not locatedin a noncombustible structure or areaprovided it is continuously attended bysomeone who can see the compressor atall times, activate the fire suppressionsystem and shut off the compressor.Also, the existing rule is modified forcompressors that are located in anoncombustible structure or area. Theymust be ventilated by intake air courseddirectly into a return air course or to thesurface and equipped with sensors tomonitor for heat and for carbonmonoxide or smoke. In addition, uponthe activation of the fire suppressionsystem, the compressor mustautomatically deenergize or shut off.

The final rule does not includeproposed paragraph (b)(2) whichprovided an additional alternativemeans of ventilating compressorinstallations located away from workingsections and near a return air coursewhere a substantial pressure differentialexists.

Comments were solicited on theexemption for compressors having acertain maximum horsepower.Comments were received bothsupporting and opposing a possiblerevision to increase the limit from 5 to30 horsepower. Because of the history ofcompressor fires, including the 1984Wilberg mine disaster which resulted in


27 fatalities, the existing limitation of 5horsepower has not been revised. Onecommenter questioned the proposalreference to 9 mine fires which startedin compressors between 1970 and 1992.The commenter suggested that the ninefires was inaccurately low andreferenced an MSHA report whichstated that 21 compressor fires occurredbetween 1977 and 1987. The preamblediscussion addressing the number offires was in relation to undergroundcoal mines. Other compressor fires haveoccurred at surface coal mines and atnoncoal mines. Regardless of thenumber of compressors affected,however, the safety concerns remain thesame.

Several commenters suggested thatthe cutoff for application of § 75.344 bechanged from 5 horsepower for allcompressors to 30 horsepower forreciprocating compressors and 5horsepower for all other types ofcompressors. The rationale for thisrecommendation was that reciprocatingcompressors of up to 30 horsepowercontain about the same amount oflubricating oil as 5 horsepowercompressors. This suggestion was notincluded in the proposal, based onMSHA information (Report No. 06–292–87 of the Industrial Safety Division,Pittsburgh Safety and HealthTechnology Center) that thepredominant hazard for fire orexplosion in reciprocating compressorsis not the lubricating oil, but rather theformation of carbonaceous deposits inthe discharge system. MSHA receivedcomments addressing the formation ofcarbonaceous deposits in the dischargesystem indicating that the use ofsynthetic oil prevents any carbonaceousaccumulation. Commenters suggestedthat all identified hazards would beeliminated through the use of syntheticoils. However, commenters also notedthat synthetic oils have a higher flashpoint.

MSHA has examined the subject ofsynthetic oils and found that syntheticoils can be formulated withpolyalphaolefins, polyglycols, silicones,esters, phosphate-esters, and di-esters asthe primary ingredient. Thesecompounds are also blended withmineral oils to form syntheticlubricants. The rate of oxidation isvaried among these compounds. Ofthese types, only silicone basedlubricants exhibit virtually no oxidationand are used primarily where extremelyhigh temperatures are expected. Also,silicone based lubricants are inherentlyfire resistant. Unfortunately, siliconebased lubricants are incompatible withreciprocating compressors and willrapidly lead to failure of the

compressor. Polyalphaolefins,polyglycols, and mineral oil blends allcontain hydrocarbons and have atendency to varnish and create depositsin air compressors. Accordingly, thefinal rule, like the existing rule, exemptscompressors of five horsepower or lessand the suggested revision to 30horsepower has not been adopted.

One commenter stated that moderncompressor technologies allow for muchsafer rotary screw compressor operationusing non-defeatable programmed safetycontrols, synthetic lubricants, automaticfire suppression and shutdown, andother precautions. Although syntheticlubricants offer some safetyenhancement, they do not fully mitigatethe hazards. Also, considering theaccident history including the Wilbergdisaster, MSHA has not provided anexemption for rotary screw compressors.

Existing § 75.344 (a)(1) requires allcompressors to be located innoncombustible structures or areas andto be equipped with a heat-activated firesuppression system. Duringinformational meetings it was brought toMSHA’s attention that in someinstances requiring compressors to beinside such a structure could present ahazard through compressor overheating.Upon reviewing this potential effect ofthe regulation, MSHA agreed. Therefore,before the existing standard couldbecome effective, MSHA stayed theapplication of paragraph (a)(1) andincluded the standard in thisrulemaking.

The final rule addresses the potentialof compressor overheating by allowing acompliance alternative to enclosing thecompressor. Heat is generated atconsiderable rates by operatingcompressors. Improperly used ormaintained compressors can present asignificant risk of fire. To minimize thishazard, the rule specifies otherinstallation and operationalrequirements as well as providing forfire detection and fire suppression. Asrecommended by commenters, the finalrule also provides for audible and visualalarms and automatic deenergization orshut-off.

Several commenters discussed theproposed revisions to paragraph (a). Onecommenter urged that the term‘‘operation’’ be clarified, noting thatcompressors which are designed toautomatically start when necessary torebuild air pressure should be protected.MSHA considers compressors that areinstalled to automatically start whennecessary to rebuild air pressure to bein operation. MSHA agrees that thesecompressors should be provided eithera noncombustible structure (or area) oran attendant. Accordingly, for the

purpose of clarifying the requirement,the final rule includes the commenter’srecommendations. Compressors whichhave been disconnected from the poweror fuel source would not be subject tothe requirement under the final rule.

Another commenter suggested thatthe person specified in paragraph (a)(1)be trained. The commenter noted thatthe attendant would be of little value ifunaware of the appropriate response toa fire. The commenter suggested that theperson know how to deenergize themachine and activate the firesuppression system manually. MSHAagrees and notes that this knowledge isrequired under the proposal byrequiring that the attendant be capableof performing these tasks. MSHAbelieves that any training necessary tomeet this capability is implicit in thestandard and the proposal has beenretained under the final rule.

Another commenter suggested that anattendant be accepted as an alternativeto noncombustible structures or areasfor a maximum of 8 hours. Thecommenter stated that 8 hours wouldprovide sufficient time for urgent roofbolting or construction work such ascoating stoppings or powering a jackhammer. After considering thecomment, the suggested time limit hasnot been adopted. MSHA believes thata continuous attendant, always withinsight of the compressor and capable ofresponding as required, provides a levelof protection equivalent to theprotection provided by an enclosure.Therefore, the final rule allows eitheralternative to be selected. It should alsobe noted that the final rule has beenrevised to require either a continuousattendant or containment in anoncombustible enclosure or area.

One commenter suggested that analternative be provided in the rule toallow for video monitoring ofcompressors as an alternative toattendance or noncombustibleenclosures. MSHA has not adopted thesuggestion since video monitoringwould not provide an equivalent levelof safety compared to either anenclosure or attendance. There wouldbe a considerable time delay inresponding to a video monitor ascompared to a nearby attendant whocould immediately shut down thecompressor, activate fire suppression,discharge fire extinguishers, apply rockdust, and take other necessary actions.

Other commenters addressed anallowable distance within which thecompressor attendant must remain. Inthe preamble to the proposal, MSHAsolicited comments on the proposedlanguage, ‘‘can see the compressor at alltimes’’ versus having the attendant


remain within some specified distance.Rationale was solicited for any specificdistances suggested. Severalcommenters supported the proposal,noting that adjustment is inherentlyprovided for high mining heights andseam undulations since a lowundulating seam would cause theattendant to remain closer to thecompressor. Another commentersuggested that a maximum distance of20 feet be specified. The commenterreasoned that a maximum distance of 20feet would assure that the attendantcould react to a fire quickly, noting thata compressor fire would propagaterapidly. The commenter also voiced aconcern over travel time in low heightmines and noted that distances over 20feet might allow a fire to get out ofcontrol before the attendant could reachthe machine.

Another commenter was concernedwith the proposed requirement in (a)(1)that a person be able to see thecompressor at all times. The commentersuggested that the term ‘‘closeproximity’’ be adopted noting that aperson could be in close proximity, e.g.in an adjacent crosscut, but not withinsight. The commenter suggested thatthis should be acceptable since theperson would still be able to activate thefire suppression system. MSHAdisagrees. The suggested situation is notacceptable since a considerable delaycould result before detection of aproblem if the person were not withinsight of the compressor. In such a casethe person would be relying on thesmell of smoke or some indirect meansof detecting a problem. Because of thepotential fire hazard associated withcompressors, reaction time is critical.MSHA continues to believe that reactiontime is appropriately minimized if theassigned person can see the compressorat all times, is capable of deenergizingthe unit, and is capable of activating thefire suppression system. While agreeingthat reaction time is critical and afterconsidering all of the comments, MSHAfinds the arguments for not specifying aset distance to be more persuasive.Therefore, the final rule permitscompressors to be continuouslyattended by a person designated by theoperator who can see the compressor atall times during its operation. Anydesignated person attending thecompressor must be capable ofactivating the fire suppression systemand deenergizing or shutting-off thecompressor in the event of a fire.

If a compressor is not enclosed inaccordance with (a)(2), the compressorcan be operated only while it can beseen by a person designated by theoperator according to (a)(1). In adopting

this approach, the proposed paragraph(a)(1) language was deleted.Commenters indicated confusion overthe similarity of proposed paragraphs(a)(1) and (b)(1) of the existing rule. Thefinal rule combines these tworequirements in (a)(1). The final rulerequires both that the person be able tosee the compressor and be capable ofactivating the fire suppression system.

Paragraph (a)(2) of the final rulerequires that compressors, if installed ina noncombustible structure or area, beventilated by intake air coursed directlyinto a return air course or to the surfaceand be equipped with sensors tomonitor for heat and for carbonmonoxide or smoke. MSHA expects thatan air quantity sufficient to cool thecompressor will be provided throughthe enclosure. The manufacturer’soperation manuals for compressorsoften specify an air quantity or amaximum ambient temperature. Thesensors required by paragraph (a)(2)must deenergize power to thecompressor, activate a visual andaudible alarm located outside of and onthe intake side of the enclosure, andactivate doors to automatically enclosethe noncombustible structure or areawhen either of the conditions inparagraph (a)(2)(i) or (ii) occurs. Thevisual alarm should be situated so thatit can be seen by persons traveling inthe intake entry immediately adjacent tothe enclosure. The sensors must alsodeenergize or shut-off the compressor inaddition to closing the doors of theenclosure.

Paragraph (a)(1)(ii) specifies that thesensors shall deenergize power to thecompressor, activate a visual andaudible alarm located outside of and onthe intake side of the enclosure, andactivate doors to automatically enclosethe noncombustible structure or areawhen the carbon monoxideconcentration reaches 10 parts permillion above the ambient level for thearea, or the optical density of smokereaches 0.05 per meter. These levels arethe same as required by the existingrule. As discussed in MSHA’s openingstatement at the ventilation rulemakinghearings, the value used for the opticaldensity of smoke is based oninformation provided from the Bureauof Mines. MSHA pointed out that, basedon comments received from the Bureauof Mines, this number is incorrect andshould be divided by 2.303 to conformto the internationally accepted term ofoptical density. MSHA’s remarks weremade in reference to the requirement in§ 75.340(a)(1)(iii)(B). The final rule alsomakes a conforming technical revisionto § 75.344(a)(2)(ii).

Paragraph (e) of the final rule requiresautomatic deenergization or automaticshut off of the compressor if the firesuppression system of paragraph (b) isactivated. A number of commenterssuggested that compressors should havean automatic shutdown feature thatdeenergizes or shuts-off the compressorwhen the required fire suppressionsystem is activated. MSHA agrees.MSHA recognizes that under § 75.1107–4 automatic deenergization is required ifthe automatic fire suppression system isactivated on unattended electricallypowered compressors.

Proposed paragraph (b)(2) has beenomitted from the final rule. Theparagraph was intended to provideadditional flexibility for compressorinstallations located away from workingsections and near a return air coursewhere a substantial pressure differentialexists. No comments were received insupport of the proposed standard, whilea number of comments were received inopposition. Commenters objecting to thestandard raised concerns aboutoverheating and stated that the revisionswere made unnecessary in view ofmodified paragraph (a). MSHA agrees.Historically, when compressors that areon fire continue to operate, they oftenreleased oil into the environment, thusincreasing the severity of the fire. Forthis reason, MSHA believes that safetyis best served by requiring compressorsto be deenergized or shut-off when thefire suppression system is activated.Commenters recommendeddeenergization in (a)(2) of the final rule.MSHA agrees and has the includedautomatic deenergization in (a)(2). Onecommenter suggested that alarms beautomatically given at the section andsurface and that two-waycommunications be provided at eachcompressor installation. Thisrecommendation has not been adoptedsince the rule provides the desired levelof safety through venting to the return,automatic fire extinguishment andclosure of doors, in addition to thealarms outside the enclosure.

Section 75.360 Preshift ExaminationThe preshift examination is a

critically important and fundamentalsafety practice in the industry. It is aprimary means of determining theeffectiveness of the mine’s ventilationsystem and of detecting developinghazards, such as methaneaccumulations, water accumulations,and bad roof.

A considerable number of commentswere received representing a range ofopinions on the changes MSHAproposed. After consideration of allcomments received, the final rule


adopts certain modifications andclarifications to the existing standard toincrease the effectiveness of the preshiftexamination. The final rule removesparagraph (e), redesignates existingparagraphs (f) through (h) as (e) through(g), revises paragraphs (a), (b), and (f)and adds new paragraphs (b)(8) through(b)(10).

Existing paragraph (a) is divided intoparagraphs (a)(1)and (a)(2) in the finalrule. Paragraph (a)(1) of the final rulecontains the existing generalrequirement that preshift examinationsare to be conducted by certified personsdesignated by the operator. Paragraph(a)(1) also modifies the existing andproposed language in response tocomments, to provide for preshiftexaminations at 8-hour periods.Paragraph (a)(2) of the proposed rulewould have allowed pumpers toconduct an examination in lieu of thepreshift examination under certainconditions. The final rule adopts thisapproach with 2 changes. The final ruledoes not require the pumper to examinefor noncompliance with mandatorysafety and health standards that couldresult in a hazardous condition anddoes require that records be made andretained in accordance with § 75.363.

A number of commenters addressedthe application of this standard at mineswhere extended, overlapping, or othernovel working shifts are employed.MSHA agrees with commenters thatevolution within the industry in shiftscheduling has presented a number ofquestions and controversies regardingthe standard which must be resolved toassure that proper preshift examinationsare conducted within suitable timeframes. Based on comments, the finalrule adopts a modification to clarify andstandardize the application of thepreshift examination in recognition ofthe use of novel shifts whilemaintaining the protection of theexisting standard.

Underground working schedules ofthree 8-hour shifts per day werevirtually standard when the previousrule was implemented. Currently asubstantial number of mining operationshave work shifts of more than 8 hours.Other operations stagger or overlapshifts providing for continuousunderground mining activities. Somemines that operate around the clockschedule persons to begin shifts at one-or two-hour intervals. In such cases,controversies and misunderstandingshave developed regarding application ofthe current standard.

Commenters suggested that preshiftexaminations should be conducted fordistinct 8-hour periods. Under thisscenario a preshift examination for an 8-

hour period would be acceptable for theentire 8-hour period regardless of shiftschedules. Other comments indicatethat this suggested modification wouldbe consistent with the original intentand language of section 303(d)(2) of theMine Act, which provides that noperson, other than certified personsdesignated to conduct the examination,is permitted to enter any undergroundarea unless a preshift examination ofsuch area has been made within 8 hoursprior to their entering the area. Acommenter stated that to allow preshiftsat more than 8-hour periods reduces theprotection envisioned by the drafters ofthe Mine Act. MSHA understands theconcerns and the critical nature of thepreshift examinations to monitor theconstantly changing conditionsunderground and has revised the ruleaccordingly to provide for anexamination at 8-hour intervals.

Under the final rule, operators willestablish the 8-hour periods for whichpreshift examinations will beconducted. Persons may enter or leavethe mine, regardless of their shiftschedule during any established periodfor which a preshift examination hasbeen conducted. However, anotherpreshift examination must be completedprior to the next 8-hour period if anypersons, other than examiners, remainin the mine. As always, no person otherthan examiners may enter anyunderground area prior to thecompletion of a preshift examination.

The final rule requires three preshiftexaminations where persons areunderground for more than 16 hours perday. At mines with only one 8-hourshift per day only one preshiftexamination per day would be required.Mines working 10-or 12- hour shiftswould conduct preshift examinationsfor each 8-hour period during whichpersons are underground. MSHA agreeswith comments that the originallegislation of the Mine Act envisionedthat preshift examinations would beconducted for each 8-hour interval thatpersons worked underground. Similar tothe existing requirement, the final ruledoes not require examinations fordesignated 8-hour periods when no onegoes underground.

MSHA recognizes that the final rulemay cause a limited number of mines toperform examinations that are notcurrently required. These affected minesdo not operate 24 hours per day butwork one or two shifts which exceed 8hours. For example, the final rulerequires two examinations per day at amine operating one 12-hour shift perday. When a mine operates two 10-hourshifts per day the final rule requiresthree examinations per day. The Agency

has concluded that, considering thespeed at which underground conditionscan change, a reasonable period must beidentified after which anotherexamination is necessary. It is notMSHA’s intent that the preshift be acontinuous examination without abeginning or an end. Rather if the mineuses regular shifts that are longer than8 hours in length, the preshiftexamination is good for an entire 8-hourinterval. Those persons who start theirwork shift later than the normal shiftstart time do not need an additionalpreshift examination during theremainder of the 8-hour period.However, a preshift will be required ifthey are to stay in the area past the endof the 8-hour period. However, inaccordance with longstanding practice,unplanned short excursions past the 8-hour period that occur infrequently willbe accepted without an additionalpreshift. For example, miners requiredto stay an additional short period oftime, such as 15 minutes to complete amechanical repair, or due to a mantripdelay, would not need an additionalpreshift. The rule simplifies andclarifies the application of the standardat mines employing creative shiftscheduling.

Comments were received suggestingthat the regulation should stipulate12:00 a.m., 8:00 a.m., and 4:00 p.m. asthe beginning of the 8-hour periods forwhich preshift examinations would berequired. This suggestion has not beenadopted. There is no safety or healthbenefit to be gained through prohibitingoperators from adopting other 8-hourintervals, e.g., 10:00 p.m., 6:00 a.m., and2:00 p.m. Also, the standard is notintended to prevent operators fromestablishing their own work times. Forexample, an operator may elect astarting time of 11:00 a.m. for a weekendproject provided the preshift iscompleted within the 3 hours prior tothe beginning of the shift.

A commenter suggested that the finalrule not require a preshift examinationfor non-coal producing shifts, wherepersons are to work in the shaft, slope,drift, or on the immediate shaft or slopebottom area. Under the commenter’ssuggestion, only that area immediatelysurrounding the bottom would need tobe examined. The rationale given for thesuggested change is that it is intendedto bring the standard into conformitywith ‘‘certain state regulatoryprograms’’. MSHA is not aware of stateregulatory programs which wouldnecessitate a change in the language ofthe final rule. Additionally, becauseareas where persons are not scheduledto work or travel are not required to beexamined under the final rule, the


change is unnecessary. Therefore, thesuggestion of the commenter has notbeen adopted.

Paragraph (a)(2) of the final ruleprovides that preshift examinations ofareas where pumpers are scheduled towork or travel are not required prior tothe pumper entering the areas, if thepumper is a certified person and thepumper conducts the specifiedexaminations. This standard recognizesthat pumpers travel to remote areas ofthe mine to check on water levels andthe status of pumps, making regularpreshift examinations impractical. Theexaminations required by pumpersinclude an examination for hazardousconditions, tests for methane andoxygen deficiency, and a determinationof whether the air is moving in itsproper direction in the area where thepumper works or travels. Theexamination of the area must becompleted before the pumper performsany other work. A record of allhazardous conditions found by thepumper must be made and retained inaccordance with § 75.363.

One commenter objected to theproposal stating that areas wherepumpers work or travel should bepreshift examined. The commenterstated that the proposed revision wouldweaken the protections provided underthe existing standard, and that the rulewould indirectly require that pumpersbe certified. The commenter noted thatmost pumpers are not certified toperform examinations, and that it wouldbe inappropriate to require ‘‘hourlyemployees’’ to obtain suchcertifications. The commenter furthersuggested that the proposed revisioncould infringe on the traditionalrelationship between labor andmanagement wherein only managementis required to be certified. The final ruledoes not require that pumpers becertified. Rather the final rule providesan option for pumpers to performexaminations for themselves if they arecertified. Otherwise, areas wherepumpers are scheduled to travel must bepreshift examined by a certified person.

The final rule maintains the existinglevel of safety. A complete examinationby a certified person is still required andthe examination will be conductedcloser to the time that work isperformed in the area. As with otherexamination requirements, no one mayaccompany the pumper during theexamination. It is important to note thatthe examination performed by thepumper under paragraph (a)(2) is notacceptable if other persons have beenscheduled to enter the area. The pumpermay only perform an examination inlieu of a preshift for himself or herself.

If, however, after the beginning of thepreshift examination, persons areassigned to enter the area, the pumpermay perform a supplementalexamination for other persons inaccordance with § 75.361, provided thatthe certified pumper is designated bythe operator to conduct suchexaminations.

Commenters asserted that pumperscannot conduct quality examinationsand effectively perform their normalwork duties. Under a previous standardreplaced in 1992, persons such aspumpers, who were required to enteridle or abandoned areas on a regularbasis in the performance of their duties,and who were trained and qualified,were authorized to make examinationsfor methane, oxygen deficiency andother dangerous conditions forthemselves. Under the final rule, eithera preshift examination must be made inaccordance with paragraph (a)(1) beforea pumper enters an area, or certifiedpumpers must conduct an examinationunder paragraph (a)(2).

One commenter cited a 1984 incidentat the Greenwich No. 1 mine wherethree miners were killed in an explosionwhile entering an idle area to work ona pump. The commenter suggested thatan effective preshift examination wouldhave prevented the accident andsuggests that both a preshiftexamination and examinations byqualified pumpers should be required.An adequate preshift examination orsupplemental examination as specifiedin the final rule, would prevent asimilar result. One of these twoexaminations is always required underthe final rule before persons enter anysuch idle area.

Also in addressing paragraph (a)(2),one commenter suggested that somecertified persons who are pumpers maynot conduct adequate examinations.According to the commenter, certifiedpersons conducting examinations underparagraph (a)(2) cannot be expected toperform at the same level as preshiftexaminers conducting examinationsunder (a)(1). MSHA expects that allcertified persons who are required toconduct examinations, includingcertified pumpers, will conduct theexaminations in accordance with thestandards.

Another commenter suggested thatpersons performing other jobs, such asrock dusters, should be permitted toperform examinations for themselves.Pumpers, unlike most other minersexcept mine examiners, travel in remoteareas of the mine and normally workalone. Persons performing work such asrock dusting, however, normally workin newer areas of the mine where

mining has only recently beencompleted and normally work as a partof a crew. Therefore, MSHA does notconsider the work assignments to besimilar enough to merit the sameconsideration and has not included thisrecommendation in the final rule.

As proposed, paragraph (a)(2) wouldhave required that the certified pumperexamine for noncompliance withmandatory safety or health standardsthat could result in a hazardouscondition, test for methane and oxygendeficiency, and determine if the air ismoving in its proper direction in thearea to be worked or traveled by thepumper. A number of commentersrecommended the deletion of therequirement that the certified pumperidentify and record noncompliance withmandatory safety and health standardsthat could result in a hazardouscondition. Commenters cited a numberof objections: the requirement woulddetract from miner safety, wouldsignificantly and unnecessarily increasethe burden on examiners, woulddiminish the quality of the examination,would require excessive judgment anddiscretion by the examiners, and requireexaminers to make predictions. Afterconsidering all submitted comments,MSHA concludes that these commentshave merit and the final rule does notrequire certified pumpers to examine forviolations of mandatory safety andhealth standards that could result in ahazardous condition.

Under paragraph (a)(2), a record of allhazardous conditions found by thepumper must be kept in accordancewith § 75.363. One commenter objectedin that all of the records resulting froma preshift examination would not berequired of the pumper, such as thelocations of air and methanemeasurements and the results ofmethane tests. The commentersuggested that the full preshift recordshould be produced just as if theexamination were done according toparagraph (a)(1). In the case of thepumper-examined area, the recordsrequired under paragraph (a)(2) willassure that mine management is madeaware of any condition which results ina hazardous condition and will facilitatecorrective actions being taken. It isimportant to note that the pumper isconducting an examination in a limitedarea only for himself or herself. This isin contrast to the various areasaddressed in paragraph (a)(1), where theexamination is in anticipation of one ormany other miners entering these areasusually on a regular basis, all of whomare relying on the examiner’s findings.In these circumstances, it is importantthat a record is made which can be


utilized to spot ongoing problems andtrends.

Paragraph (b) of the rule specifies thenature of the preshift examinations andthe locations where a preshiftexamination is required. Proposedparagraph (b) would have required thatthe person conducting the preshiftexamination would examine fornoncompliance with mandatory safetyor health standards that could result ina hazardous condition. Afterconsidering all submitted comments,the final rule does not contain thisrequirement.

A number of commentersrecommended the deletion of therequirement to identify and recordnoncompliance with mandatory safetyand health standards that could result ina hazardous condition. Variouscommenters stated that the proposedrequirement: would distract theexaminer from the most importantaspects of the preshift examination;would require predictions; would be anunrealistic expectation; and/or isdesigned only to facilitate enforcementactions. Commenters also suggested thatthe proposal would result in a shift inthe focus of preshift examination fromtrue hazards to noncompliance.

Other commenters objected that theproposed requirement to examine fornoncompliance with mandatory safetyor health standards that could result ina hazardous condition is so vague thatit could detract from miner safety. Onecommenter suggested that the examinerswould spend their time performingpermissibility checks, torquing roofbolts, measuring roof bolt spacing, andsimilar tasks which represent asignificant departure from theexaminers traditional duties.

Another commenter expressed theopinion that paragraph (b) shouldrequire that all violations of mandatorysafety or health standards be recordedand it should not be limited to thosethat could result in hazardousconditions. Preshift examinations assessthe overall safety conditions in themine; assure that critical areas areproperly ventilated; assure that the mineis safe to be entered by miners on theoncoming shift; identify hazards,whether violations or not, for theprotection of miners; and through thisidentification facilitate correction ofhazardous conditions.

The preshift examinationrequirements in the final rule areintended to focus the attention of theexaminer in critical areas. Thisapproach is consistent with thefundamental purpose of preshiftexaminations which is to discoverconditions that pose a hazard to miners.

MSHA is persuaded that to requireexaminers to look for violations thatmight become a hazard could distractexaminers from their primary duties.The final rule, therefore, does not adoptthis aspect of the proposal.

Paragraph (b)(1) of the final ruleadopts the proposal and clarifies thatpreshift examinations are to includetravelways in addition to roadways andtrack haulageways. Duringinformational meetings, commentersindicated that the terms ‘‘roadways’’and ‘‘track haulageways’’ are associatedwith areas where mobile poweredequipment is operated. By including theterm ‘‘travelways,’’ the rule clarifies thatareas where persons are scheduled totravel on foot are to be included, sincehazards may also develop in these areas.

One commenter suggested that theproposal would greatly increase the areathat must be preshift examined, eventhough the requirement is limited toonly those travelways where miners arescheduled to work or travel. Thiscommenter suggested that in largemines many more areas than wouldactually be used by miners would haveto be preshift examined. The premise ofthe preshift examination is that all areaswhere miners will work or travel beexamined for hazards. The final rulechange concerning ‘‘travelways’’ isintended only to clarify that, whenminers are scheduled to use these areas,they must be preshift examined first.The final rule, therefore, does notexpand the existing scope to the preshiftexamination requirements.

The language of the existingparagraph (b)(1) referring to, ‘‘* * *other areas where persons are scheduledto work or travel during the oncomingshift’’ is transferred to a new paragraph(b)(10) with conforming changes, asproposed. MSHA received no commentson moving this provision to paragraph(b)(10). Commenters did respond to thephrase in proposed paragraph (b)(1)requiring preshift examinations ofroadways, travelways and trackhaulageways where persons are ‘‘* * *scheduled, prior to the beginning of thepreshift examination to work or travelduring the oncoming shift.’’ Thepurpose of this proposal, which isadopted in the final rule with onlyclarifying changes, is to permit workand mining personnel to be rescheduledafter the start of a shift. Preshiftexaminations, by their nature, must becompleted before the start of the shift.Changes in conditions, however, such asa breakdown of equipment, can alterplanned work schedules. Toaccommodate these circumstances, thefinal rule requires mine operators todesign preshift examinations around the

best information available at the timethe preshift begins. If changes must bemade, § 75.361 specifies that areas notpreshift examined be covered by asupplemental examination performedby certified persons before miners enterthe area.

One commenter objected that wasconfusing and should be modified.Other commenters foresaw possibleabuses of the flexibility offered by therule with some operators performingsupplemental rather than preshiftexaminations, claiming that assignmentswere made after the preshiftexamination begins. After consideringthe comments, MSHA has retained theproposed flexibility to preshift examineareas where miners are scheduled towork or travel. To require more thanthis would be impractical.

Section 75.360(b)(3) of the final rulerequires preshift examinations ofworking sections and areas wheremechanized mining equipment is beinginstalled or removed if anyone isscheduled to work on the section or inthe area during the oncoming shift. Adiscussion of the reproposal ofprovisions concerning the installationand removal of mechanized miningequipment is presented in the GeneralDiscussion section of this preamble. Aswith the existing rule, the examinationincludes working places, approaches toworked-out areas, and ventilationcontrols on these sections or in theseareas. The final rule, like the proposal,adds a new requirement that theexamination also include a test of theroof, face and rib conditions on thesesections or in these areas.

Proposed changes to paragraph (b)(3)not adopted in the final rule would havealso required preshift examination ofsections not scheduled to operate butcapable of producing coal by simplyenergizing the equipment on thesection. Also, proposed changes toparagraphs (c), (c)(1), and (c)(3)specifying where air volumemeasurements were to be taken on thesesections have also not been adopted inthe final rule.

The new requirement to test the roof,face and rib conditions is added becauseof the importance of this test to thesafety of miners. In newly mined areas,checking roof, face and rib stability ismost important to preventing injuriesand death. Comments were received insupport of the revision, citing accidentswhich might have been prevented hadsuch tests been adequately performedduring preshift examinations. Onecommenter, when suggesting newwording for paragraph (b)(3), indicatedthat the requirement to test the roof, faceand rib conditions should be deleted but


did not offer any rationale for thesuggested deletion. Another commentersuggested that the preshift examinationshould only require a visualexamination of the roof, rather than aphysical examination. Physicalexaminations of the roof, such as‘‘sounding,’’ have been a historicallyaccepted method for examiners to testroof competency. Whenever anexaminer has a question as to whethera section of roof is competent, such atest should be performed.

Comments were mixed on MSHA’sproposed revision to include idleworking sections as part of the preshiftexamination. The proposal is notretained in the final rule. Somecommenters objected to the proposal asunnecessary, burdensome, orimpractical. Commenters believed thatthe existing § 75.361 requirement forsupplemental examinations prior toanyone entering into such an area wassufficient. Commenters also stated thata preshift examination in these areascould introduce a false sense of securityand that the effect would be to divertpreshift examiners from more importantduties. One commenter stated that theproposed requirement would beinconsistent with and contradictory tothe basic concept of preshiftexaminations. Another commenterobjected to MSHA’s statement in thepreamble to the proposal that there is areasonable likelihood that miners will atsome point during a working shift entersections that are set up to mine coal.

In support of the proposedrequirement to preshift examine idlesections, one commenter citedexplosions at the Red Ash Mine in 1973,the Scotia Mine in 1976, the P&P Minein 1977, the Ferrell #17 in 1980, theGreenwich #1 Mine in 1984, and the1994 explosion at the Day Branch No. 9Mine in Kentucky. As the commenterpointed out, in each of these accidentsminers were sent into an area that hadnot been preshift examined. However,none of these accidents were the resultof miners entering areas that wouldhave been covered by the proposal. Ineach instance, miners entered an areawhere mining had ceased, but could notbe resumed by simply energizingequipment. Another common thread ineach of these explosions was the failureof the operator to conduct the requiredsupplemental examination prior tominers entering the area on anunscheduled basis.

Paragraph (b)(4) of the final rulerequires preshift examinations toinclude approaches to worked-out areasalong intake air courses and at theentries used to carry air into worked-outareas if the intake air passing the

approaches is used to ventilate workingsections where anyone is scheduled towork during the oncoming shift. Theexamination of the approaches to theworked-out areas is to be made in theintake air course immediately inby andoutby each entry used to carry air intothe worked-out area. The examination ofthe entries used to carry air into theworked-out areas is to be at a pointimmediately inby the intersection ofeach entry with the intake air course.The standard is intended to assure thatminers are not exposed to the hazardsassociated with ventilating workingsections with contaminated air whichhas passed through a worked-out area.The requirement is consistent with the§ 75.301 definition of ‘‘return air’’ andwith § 75.332 which provides thatworking sections and other specifiedareas must be ventilated with intake air.

Commenters correctly noted that aclarification was needed in the firstsentence of proposed paragraph (b)(4) toindicate that the examination at thespecified points is only required if theintake air passing the approaches isused to ventilate working sectionswhere anyone is scheduled to workduring the oncoming shift. Commenterssuggested that an examination shouldnot be required if the intake air is notused to ventilate working sections or ifno one is scheduled to work on thesection. This was the result intended bythe proposal and the final rule has beenrevised accordingly.

One commenter also suggested thatthe requirement in paragraph (b)(4) isunnecessary because the safeguards inthe approved mine ventilation planshould prevent an air reversal in aworked-out area in which this air wouldenter the intake air course. Thecommenter offered the example of aworked-out area connected directly to ableeder system. MSHA agrees that whenproper safeguards are in place andoperating as intended, air reversals areunlikely. However, roof falls and otherobstructions in the worked-out area orin the bleeder can cause air reversals,permitting return air to enter the intakeand be transported to the workingsection. Without a suitable examination,this condition would go undetected andcould lead to disaster. While not exactlythe same, the explosion at the PyroMine in 1989, which resulted in thedeaths of 10 miners, was the result of asomewhat similar set of circumstances.A water blockage in the bleeder entrythat combined with changes to certainventilation controls led to methanemigrating from the worked-out area ontothe longwall face. MSHA’s report of thisaccident concludes, in part, thatchanges that occurred during the mining

of the longwall panel and in the bleederentries caused a fragile balance of airflows to exist in the ventilation systemthat permitted methane to migrate fromthe gob and to accumulate near thelongwall headgate.

One commenter agreed with theproposal and discussed the need toassure that miners are not exposed tothe hazards associated with ventilatingworking sections with return air.

Essentially, the final rule requires thatat each applicable approach, threeexaminations must be made;immediately inby and outby theapproach in the intake entry and in theapproach itself immediately inby theintersection with the intake entry.Situations exist where multipleopenings along an intake lead into aworked-out area. Under someconditions intake air enters theupstream openings, passes through theworked-out area, and then re-enters theintake. The examination required byparagraph (b)(4) is designed to assurethat such a condition is detected. Also,the examination detects any change inventilation entering the worked-out areawhich may warrant follow-up orcorrective actions to assure that theworked-out area is ventilated.

Paragraph (b)(6) of the final ruleadopts the proposal modifying theexisting rule. No comments werereceived on this aspect of the proposal.The final rule in paragraph (b)(6)(i)requires preshift examinations toinclude entries and rooms developedafter November 15, 1992 (the effectivedate of the existing rule), and developedmore than 2 crosscuts off an intake aircourse without permanent ventilationcontrols where intake air passes throughor by these entries or rooms to reach aworking section where anyone isscheduled to work during the oncomingshift. Similarly, under (b)(6)(ii) theexamination must include entries androoms developed after November 15,1992, and driven more than 20 feet offan intake air course without a crosscutand without permanent ventilationcontrols where intake air passes throughor by these entries or rooms to reach aworking section where anyone isscheduled to work during the oncomingshift.

Existing paragraph (b)(6) requires thata preshift examination be made in allentries and rooms driven more than 20feet off an intake air course without acrosscut or more than 2 crosscuts off anintake air course without permanentventilation controls where intake airpasses through or by these entries orrooms to a working section whereanyone is scheduled to work during theoncoming shift. MSHA proposed


modifications to existing paragraph(b)(6) based on concerns raisedfollowing publication of the existingrule on May 15, 1992. Commenters atthat time indicated that extensiverehabilitation would be required at anumber of mines to implement thestandard in the rooms and entriesdescribed in the rule, causingdiminished safety for miners performingthe rehabilitation work. Commentersnoted that some areas had beentimbered heavily and cribbed because ofadverse roof conditions and thatrehabilitation would unnecessarilyexpose miners to roof falls and rib rollswhile removing or repositioning roofsupport. In addition, roof conditions insome areas would remain hazardouseven after rehabilitation. Thecommenters also noted that many suchareas had been in existence for manyyears without incident and that anymethane liberation had long sincestopped due to the passage of time.They noted that some areas cannot beeffectively sealed and that the risksassociated with rehabilitation andsubsequent physical examinationswould greatly outweigh the safetybenefit to be gained. MSHA recognizesthe legitimate concerns raised by thecommenters and the final rule requirespreshift examination of entries androoms developed after November 15,1992 and driven more than 20 feet offan intake air course without a crosscutor more than 2 crosscuts off an intakeair course without permanentventilation controls where intake airpasses through or by these entries orrooms to a working section whereanyone is scheduled to work during theoncoming shift. MSHA believes,however, that the conditions addressedby paragraph (b)(6) are the result ofimproper mining practices in the past.These mining systems should be revisedin the future to avoid poor conditions,or the areas affected should be fully andreliably ventilated and be examined.Also, the final rule applies only toentries and rooms developed after theeffective date of the existing rule. Assuch, the mining industry was on noticeof the shortcomings of mining practicesthat left entries and rooms of the typeaddressed by the standard.

Paragraph (b)(8) retains the proposalrequiring preshift examinations toinclude high spots along intake aircourses where methane is likely toaccumulate, if equipment may beoperated in the area during the shift. Asnoted in the proposal, it has long beenrecognized that methane canaccumulate in high areas with noindications being detected in the lower

portions of the opening. As mobileequipment passes under these areas ora conveyor belt is put into operation, themethane is pulled down and mixedwith the air in the entry and may beignited. The final rule addresses thehazards of undetected accumulations ofmethane in high spots by requiringpreshift examinations in such areas inintake air courses if equipment will beoperated in the area during the shift.

Several commenters requested thatMSHA clarify the term ‘‘high spots.’’One commenter stated that many hourswould be necessary to examine everyindentation in the roof of a large mineand stated the belief that the turbulencecreated by passing equipment wouldrender harmless any of the smallamounts of methane that might possiblyaccumulate. Another commenterbelieved the requirement wasunnecessary because there has neverbeen a problem with methaneaccumulating in intakes in quantitiessufficient to cause an explosion. Onecommenter suggested that therequirement should only be applicableto mines with a demonstrated history ofmethane accumulations, noting thatalthough mines are considered likely toliberate methane, it is not likely that allmines will accumulate methane in highspots.

Another commenter suggested thatpreshift examinations should berequired in all high spots in intakes,returns, belt entries, and track haulageentries. The commenter also objected tolimiting the examination in intakes onlyto areas where equipment may beoperated during the shift. Thecommenter observed that methane canaccumulate quickly in high spots andthat it is critical to detect the methanebefore it creates a danger. Thecommenter notes several accidentsinvolving methane accumulations inhigh spots, including: Meigs No. 31Mine in 1993 where methane in a roofcavity was ignited by a torch; VP–5Mine in 1992 when methane in a cavitywas ignited by a torch; Ferrell No. 17Mine in 1980 where, according to thecommenter, methane may haveaccumulated in a cavity in the belt entryroof and may have been ignited by atrolley powered vehicle; and in the VP–6 in 1982 where methane in a high spotwas ignited by a trolley powered vehicletraveling through the area. Thecommenter stated that accumulations ofmethane in high spots can be ignited byany number of sources.

A meaningful preshift examinationrequires that conditions which can leadto an explosion or ignition be detectedand corrected before miners begin theirwork. In addition to the accidents cited

above attributed to methaneaccumulations in high spots, the ItmannNo. 3 Mine explosion occurred when atrolley powered vehicle ignited methanein a high spot, resulting in the death of5 miners and severe burns to 2 otherminers. The phrase ‘‘high spots wheremethane is likely to accumulate’’ shouldbe understood in the coal miningindustry. Experienced miners, and inparticular preshift examiners andcertified persons, can readily recognizea high spot where methane is likely toaccumulate. Also, MSHA for many yearshas considered preshift examinations tobe inadequate where examinations didnot include methane tests in these areas.An examination of ‘‘every indentation,’’as foreseen by one commenter is notexpected nor intended by paragraph(b)(8), which specifies that preshiftexaminations be used to identifymethane hazards by testing in theappropriate locations. The final ruledoes not adopt the suggestion thatmethane examinations be based on mineliberation history since significantmethane liberation may begin or cangreatly increase at any time. Also, thepotential for a dangerous accumulationof methane in a high spot is influencedby mine ventilation, particularly the airvelocity in the entry.

One commenter suggested that therule require tests only in ‘‘unventilatedhigh spots’’ along intake air courses.The final rule does not adopt thisapproach. The purpose of the preshiftexamination is to detect hazards, in thiscase accumulations of methane.Nominal ventilation in a high roofcavity may not be sufficient to sweepaway methane and an accumulationcould exist. The final rule directs anexaminer’s attention to such situations.

Proposed paragraph (b)(9) is modifiedin the final rule. Paragraph (b)(9) of thefinal rule requires preshift examinationsat underground electrical installationsreferred to in § 75.340(a), except thosewater pumps listed in § 75.340(b)(2)through (b)(6), and areas wherecompressors subject to § 75.344 areinstalled if the electrical installation orcompressor is or will be energizedduring the shift. The proposal wouldhave exempted all water pumps fromthe requirements of paragraph (b)(9).

One commenter objected to theexemption for pumps andrecommended that all pumps beexamined pointing out that some pumpsare large, high-horsepower units. Thecommenter noted a 1994 case inVirginia where a 200 horsepower pumpexploded. Pumps of this type may be inlocations or in applications that wouldnot be examined by pumpers underparagraph (a)(2). The final rule responds


to this issue by requiring that all pumpsshould not be exempted from thestandard. Paragraph (b)(9) requirespreshift examinations of all pumps,except those specified in § 75.340(b)(2)through (b)(6). Pumps specified in§ 75.340(b)(2) through (b)(6) and otherpumps that operate automatically orthat otherwise may be energized aregenerally in the more remote areas ofthe mine and are to be examined weeklyin accordance with § 75.364.

Pumps which will be examined bycertified pumpers in accordance withparagraph (a)(2) are not covered by thefinal rule because of the limited hazardsthey pose and because certifiedpumpers would themselves conductexaminations of this equipment inaccordance with paragraph (a)(2).Examinations by pumpers at theselocations will assure that methane hasnot accumulated and that the equipmentis not in a condition to create a fire orignition source.

A review of the accident historyreveals a number of fires in equipmentthat, under the final rule, would besubject to preshift examinations. Forexample, the compressor that MSHAidentified as the probable cause of thefire in the Wilberg Mine, which killed28 miners, would have required apreshift examination under (b)(9) of thefinal rule. Additionally, MSHA hasidentified several fires associated withrectifiers and transformer installationsin the mining industry. One of thesetransformer fires was discovered duringa preshift examination.

One commenter supported proposedparagraph (b)(9) and noted a number ofignitions involving trolleys. Thecommenter also noted that historydemonstrates that other electricalinstallations present ignition or firehazards which should be examinedbefore each shift.

One commenter incorrectlyunderstood proposed paragraph (b)(9) tonot require preshift examinations ofareas where compressors subject to§ 75.344 are installed if the compressoris or will be energized during the shift.The standard does require preshiftexaminations of such equipment, whichincludes all compressors except thosewhich are components of equipmentsuch as locomotives and rock dustingmachines and are compressors of lessthan five horsepower.

Paragraph (b)(10) adopts the proposalthat preshift examinations include otherareas where work or travel during theoncoming shift is scheduled prior to thebeginning of the preshift examination.This provision recognizes that workrequirements and situations may changeafter the preshift examination has

begun. Often, once the examination hasstarted it is not possible to contact theexaminers to direct them to newlyidentified areas where miners will work.In these cases, a supplementalexamination is required before personswork or travel in these areas. Asdiscussed in the preamble to theproposal, paragraph (b)(1) requirespreshift examinations of anyunderground area where persons arescheduled to work or travel during theoncoming shift. Under the existing rule,an operator did not have the flexibilityto modify work assignments after thepreshift examination had begun, unlessit was possible to contact and redirectthe examiners to perform a preshiftexamination before the beginning of theshift. Commenters in general supportedthe proposal. One commenter, however,while supporting the change expressedconcern that the provision could beabused. MSHA does not anticipateabuse of the rule and believes it to bea reasonable approach to assuring thatareas where persons work or travel areexamined.

As discussed above, the final ruledoes not adopt the proposed revisions toparagraphs (c), (c)(1), and (c)(3) andinstead retains the language of theexisting standard. While commenters toproposed paragraphs (c), (c)(1), and(c)(3) objected to expanding air volumemeasurements made during preshiftexaminations to sections where coalcould be mined by simply energizingthe equipment, no comments werereceived objecting to retaining therequirement for areas where equipmentis being installed or removed. An in-depth discussion of the reproposal ofprovisions concerning the installationand removal of mechanized miningequipment is presented in the GeneralDiscussion section of this preamble.

Paragraph (f) of the final rule sets outthe requirements for recording andcountersigning both the results of thepreshift examination and actions takento correct hazardous conditions foundduring the preshift examination. Thefinal rule adopts the following proposedrevisions to the existing rule: a record ofthe results of the preshift examination isrequired to be made; the results ofmethane tests are required to be madein terms of the percentage of methanefound; and a certified person is requiredto record the actions taken to correcthazardous conditions found during thepreshift examination.

Additionally, paragraph (f) of theproposal would have requiredcountersigning by both the mineforeman and the superintendent orequivalent individual to whom the mineforeman reports. The final rule does not

require this second level countersigning.Also, the final rule allows an officialequivalent to a mine foreman to sign therecords. Finally, the final rule allows forsecure storage of records in a way thatis not susceptible to alteration and therecords can be kept in a book or in acomputer system.

Commenters suggested that the finalrule only require the examiner to recorduncorrected hazardous conditions andnot those which were corrected by theend of the shift. Commenterscharacterized the reporting of correctedhazardous conditions as unnecessaryand unjustified by the accident history.

MSHA did not adopt the proposal torecord corrected defects found duringthe fan examination required by§ 75.312. MSHA believes, however, thata record of all hazards found during thepreshift examination, including thosecorrected, is necessary. The recordserves as a history of the types ofconditions that are being experienced inthe mine. When the records are properlycompleted and reviewed, mineoperators can use them to determine ifthe same hazardous conditions areoccurring repeatedly and if thecorrective action being taken iseffective. Additionally, this record canpermit mine management, therepresentative of miners, and therepresentative of the Secretary to betterfocus their attention duringexaminations and inspections. Thesafety value of a complete record isillustrated by the 1989 explosion at PyroMining Company’s William StationMine in which 10 miners were killed.MSHA’s accident investigation reportconcludes that methane concentrationsof up to 6.5 percent were detected in theexplosion area prior to the explosion butreports by the mine foreman for the shiftfailed to record the presence of thesedangerous accumulations of methane orshow the action taken to correct thecondition. The investigation furtherfound that the failure to record thesemethane accumulations in theappropriate record books preventedmanagement officials and otherinterested persons from learning of thehazardous condition and initiatingcorrective action. In light of the record,the final rule adopts the proposal andrequires the examiner to record theresults, whether corrected or not, of thepreshift examination and the actiontaken to correct hazardous conditionsfound during the preshift examination.This would include hazardousconditions and their locations and theresults of methane and airmeasurements required to be madeelsewhere in § 75.360.


As with other records required by thisrule, the records of preshiftexaminations may be kept either insecure books that are not susceptible toalteration or electronically in acomputer system so as to be secure andnot susceptible to alteration. A detaileddiscussion of record books and the useof computers to maintain records can befound in the General Discussion of thispreamble.

A variety of comments were receivedregarding the countersigning of preshiftrecords by the mine foreman, and thetime permitted for countersigning. Thefinal rule adopts the proposal that themine foreman or equivalent mineofficial must countersign the record ofthe preshift examination by the end ofthe mine foreman’s next regularlyscheduled working shift. The mineforeman is in a position of responsibilityfor the day-to-day operation of the mine.It is essential for the health and safetyof the miners that the mine foreman befully aware of the information containedin the preshift examination reports so asto be able to allocate resources toaddress safety problems. Allowing untilthe end of the mine foreman’s nextregularly scheduled working shift tocountersign the reports providessufficient flexibility to make compliancepractical while assuring that the mineforeman is aware of the results of theexamination in a reasonably timelymanner.

Some commenters suggested that thetime for countersigning is unnecessarilylong, and that the final rule shouldrestore a previous requirement thatcountersigning be completed‘‘promptly.’’ The term ‘‘promptly’’involves ambiguity that is eliminated byspecifying the time for countersigningthe preshift examination record. Therulemaking record does not show thatthe time set by the final rule wouldexpose miners to safety or health risks.Commenters suggested that the term‘‘mine foreman’’ be replaced by a‘‘certified person responsible forventilation of the mine or his designee.’’Another commenter suggested that therecord could be countersigned by themine foreman or any other mine officialresponsible for the day-to-day operationof the mine. Commenters stated thatsome operations no longer use the terms‘‘mine foreman,’’ ‘‘mine manager,’’ or‘‘superintendent’’. To provide foralternative management titles, the finalrule incorporates the phrase ‘‘orequivalent mine official.’’

Numerous comments were receivedregarding the proposal for second levelcountersigning of the preshiftexamination record by the minesuperintendent, mine manager, or other

mine official to whom the mine foremanis directly accountable, within 2scheduled production days after thecountersigning by the mine foreman.The final rule does not retain thisproposed requirement. A detaileddiscussion of the subject of second levelcountersigning can be found in theGeneral Discussion section of thispreamble.

Paragraph (f) of the final rule alsocontains revisions to the existing rule toallow for electronic storage of records.Paragraph (g) requires that the recordsrequired by § 75.360 be maintained at asurface location at the mine for one yearand be made available for inspection byauthorized representatives of theSecretary and the representatives ofminers. A discussion of commentsconcerning the use of computers tomaintain records can be found in theGeneral Discussion of this preamble.

Section 75.362 On-Shift ExaminationLike the preshift examination, the on-

shift examination of working sections isa long accepted safety practice in coalmining. As coal is extracted, conditionsin the mine continually change andhazardous conditions can develop.Because the mining environmentchanges constantly during coalproduction, this examination identifiesemerging hazards or verifies thathazards have not developed since thepreshift examination. Generally, the on-shift examination includes tests formethane and oxygen deficiency, anexamination for hazardous conditions,and air measurements at specifiedlocations.

The final rule adopts proposed§ 75.362 with the exception thatrevisions have been made to theproposed provisions dealing with anexamination for compliance with themine ventilation plan requirements forrespirable dust control.

The final rule redesignates existing(d)(1)(i) and (ii) as (d)(1)(ii) and (iii),revises paragraphs (a)(1), (c)(1),(d)(1)(iii) and (d)(2), removes paragraph(a)(2), and adds new paragraphs (a)(2)and (d)(1)(i). Additionally, therequirements of existing paragraphs (g)and (h), recordkeeping and retention,are transferred to § 75.363, Hazardousconditions, posting, correcting, andrecording. New paragraphs (g)(1) and(g)(2) are also added by the final rule.

The word ‘‘on-shift’’ has been addedto the first sentence of paragraph (a)(1)for clarity and consistency with otherparagraphs of § 75.362. MSHA did notreceive any comments on this proposedrevision. Paragraph (a)(1) is also revisedas proposed to require a certified persondesignated by the operator to conduct

an on-shift examination of each sectionwhere anyone is assigned to workduring the shift and any area wheremechanized mining equipment is beinginstalled or removed during the shift.The existing rule required that an on-shift examination be performed only onsections where coal is produced andareas where mechanized miningequipment is being installed orremoved. Some commenters agreed thatmany of the same hazards exist on asection whether coal is being producedor not. Commenters gave severalexamples of activities that take place onnon-coal producing sections includingequipment repair and maintenance,cutting and welding, rockdusting, clean-up, and roof bolting. As indicated bythese commenters, all of these activitiespresent the potential for a seriousaccident. One commenter arguingagainst the proposed change stated thatthe preshift and supplementalexaminations already address the safetyconcerns to which the proposal wasdirected. While MSHA considers thepreshift and supplemental examinationsto be of great importance in providinga safe work environment, theseexaminations are performed prior toworkers on a shift entering the mine or,in the case of the supplementalexamination, in an area of the mine thathas not been preshift examined. The on-shift examination is intended to addresshazards that develop during the shift.The concept of the on-shift examinationis not new. On-shift examinations ofcoal producing sections have beenrequired since the enactment of theFederal Coal Mine Health and SafetyAct of 1969.

Another commenter arguing againstexpanding the on-shift examinationrequirement to non-coal producingsections stated that requiring on-shiftexaminations of areas other thanworking sections would detract fromother required examinations. On-shiftexaminations on coal producingsections are normally conducted bysection foremen who spend the vastmajority of the shift on the section theyare supervising. These individuals willnot normally conduct the on-shiftexaminations in non-coal producingsections. These examinations will beconducted by certified persons assignedto work in these areas or other certifiedpersons assigned to conduct theseexaminations. MSHA does not,therefore, foresee reduced attention toexaminations in working sections.

Another commenter suggested thatthe requirements for on-shiftexaminations be expanded further thanproposed. The commenter stated thatmany of the same types of activities that


occur on non-production shifts on thesections also occur in outby areas ofmines. In support of thisrecommendation the commenterpointed to 4 explosions which occurredin outby areas of the mines. Thoseaccidents were the explosions at theGreenwich Collieries No. 1 Mine inPennsylvania in February 1984 where 3miners were killed; the explosion at theDay Branch Mine in Kentucky in 1994where 2 miners lost their lives and; anignition at the Loveridge No. 22 Mine inWest Virginia in 1992 that burned 1miner. In each accident, severalviolations of safety standardscontributed to the explosion or ignition,including inadequate or entirely omittedexaminations required by standards ineffect at the time. Compliance withthose safety standards would havesignificantly reduced the likelihood ofthese tragic accidents occurring.Likewise, requirements of this final rule,such as the requirements for preshiftand supplemental examinations in areaswhere persons are assigned to work ortravel, would have served well toprevent these accidents.

The final rule requirements for on-shift examinations focus on the areasmost likely to develop hazards during ashift. Expanding the examinationrequirements further is not supported bythe record nor needed for miner safety.

As proposed, the final rule alsorevises paragraph (a)(1) to clarify thatsufficient on-shift examinations must beconducted to assure safety. Onecommenter suggested that MSHAshould include language to require morethan one examination if necessary forsafety, as provided for in the previousstandard. The final rule adopts thisapproach and requires that at least onceduring each shift, or more often ifnecessary for safety, a certified persondesignated by the operator mustconduct an on-shift examination of eachsection where anyone is assigned towork during the shift and any areawhere mechanized mining equipment isbeing installed or removed during theshift. As with other changes to thissection, comments were received bothsupporting and opposing the change.One commenter in opposition to thestandard argued that although theoperator is required to maintain a safework environment at all times,documentation should not be requiredfor each inspection that is made of theworking environment throughout theshift. The commenter is correct instating that the rule, in § 75.363,requires additional documentation.However, the only additionaldocumentation required will be forhazardous conditions found during the

additional on-shift examinationconducted on non-coal producingsections where miners are working. Theadditional documentation required doesnot override the need for the standard.Another commenter suggested that theterm ‘‘more often if necessary for safety’’be changed to ‘‘more often if necessaryfor safety as determined by the operatordepending on the mining conditions atthe time.’’ This commenter stated thatconducting additional checks for safetyis a current practice and individualsworking on the section, including thesection foreman, are the most familiarwith conditions in that area and shouldmake the determination whetheradditional examinations are needed.MSHA agrees with this commenter thatpersons working on a section are in thebest position to identify the need foradditional examinations. The suggestedlanguage has not been adopted,however, because MSHA believes thatthis determination should not be limitedto persons working on the section.

Another commenter supported theproposal and listed explosions that haveoccurred which, in the opinion of thecommenter, could have been preventedhad additional on-shift examinationsbeen made. MSHA agrees that there areoccasions when additional on-shiftexaminations are necessary for safetyand, therefore, the final rule requiresthat on-shift examinations be conductedat least once each shift, or more often ifneeded for safety.

The final rule retains the existingprovision of paragraphs (a)(1), (c)(1) and(c)(2) requiring an on-shift examinationof areas where mechanized miningequipment is being installed orremoved. An in-depth discussion of thereproposal of provisions concerning theinstallation and removal of mechanizedmining equipment is presented in theGeneral Discussion section of thispreamble.

Paragraph (a)(2) adds a new on-shiftexamination requirement to addressrespirable dust control. Under the finalrule, before coal production begins on asection, an examination for compliancewith the dust control measuresestablished in the mine ventilation planmust be completed. This examinationincludes measurement of air quantitiesand velocities, water pressures and flowrates, a check for excessive leakage inthe water delivery system, and checks ofthe number of operating water spraysand their orientation as well as theplacement of section ventilation controldevices.

Assuring full compliance with theserequirements is important insafeguarding the health of miners.Human and financial costs demonstrate

the need for further attention. In 1990,approximately 2000 deaths wereassociated with Coal Worker’sPneumoconiosis and the total number ofdeaths between 1968 and 1990 wereover 55,000. As of 1993, total annualBlack Lung Program costs were over$1.3 billion and the cumulative totalcost had exceeded $30 billion.

Agency experience shows that neededattention has not always been given tothe proper functioning of respirable dustcontrols. For example, a series of specialspot inspections, undertaken in 1991 toconduct checks of the dust controlparameters during the course of workingshifts, revealed that 21 percent of the781 mining units sampled were notcomplying with one or more of theirdust control parameters. In its 1992report, an MSHA Task Grouprecommended coal mine operators berequired to make periodic on-shiftexaminations to verify that the mineventilation plan parameters are in placeand functioning as intended. MSHAconsiders on-shift examinations ofrespirable dust controls an importantpart of reasonable and prudentrespirable dust control strategy.

Several methods of measuring waterspray pressures would be acceptable.For example, water flow and pressurecan be monitored through theinstallation of an in-line water meterand a pressure transducer. Waterpressure can also be measured bypermanently installing a pressure gaugeon a machine. Operators woulddetermine the working relationshipbetween the pressure gauge reading andthe actual operating pressure at thesprays. Once the working relationshiphas been established, the gauge pressurecould be used to indicate the actualspray pressure specified in the mineventilation plan for a given number andtype of operating sprays.

Measurement of any required waterflow rate could be accomplishedthrough the installation of a flowmeter.A flowmeter provides a direct andreliable measurement and is thepreferred method of determining waterflow rate. Another acceptable method ofdetermining flow rate would be toestablish the relationship between thewater pressure and the spray orificediameter, either through engineeringdata or through actual tests. Onceestablished, the water pressure gaugereading could be used to reliablyindicate a flow rate for a specificnumber of sprays at a given orifice size.

One commenter, while generallysupportive of the requirement for an on-shift examination of respirable dustcontrols, expressed concern overpermitting the use of in-line flowmeters


and pressure transducers. Thecommenter stated that leaks in thelocation of the flowmeter and pressuretransducer could go undetected,resulting in a loss of pressure and flowat the sprays. MSHA agrees thatundetected leaks could result inimproper operation of the system. Toaddress this point, the final rule hasbeen revised from the proposal torequire that a check for excessiveleakage in the water delivery system bemade during the on-shift. Thiscommenter also suggested that use ofincorrect spray nozzles could result inimproper operation of the system thatwould not be detected with in-lineflowmeters and pressure transducers.MSHA would expect that as part of theexamination of the number of operatingsprays a check would be made to assurethat the proper sprays are being used.

The final rule requires that thenumber of water sprays and theirorientation be included in theexamination. While spray orientation isimportant in air-directing spray systems,such as sprayfans and shearer-clearers,MSHA does not intend that preciseangles be determined during eachexamination. Rather, the examinerwould be responsible for assessingwhether the direction and orientation ofthe sprays are generally correct and inaccordance with the requirements of themine ventilation plan.

The final rule also requires that theworking section ventilation and controldevice placement be examined forcompliance with the mine’s ventilationplan. Mine ventilation, particularlywhere coal extraction occurs, is a basicrespirable dust control measure.

Any other respirable dust controlsspecified in the approved mineventilation plan are also included in thescope of the examination required underthe final rule. An example of suchcontrols is the cleaning andmaintenance procedures for a wet bedscrubber installed on a continuousmining machine. The examinationwould include a check to assure that airinlets and discharges are not plugged. Itis not MSHA’s intent that the airquantity produced by a machine-mounted scrubber be measured as partof the on-shift examination required byparagraph (a)(2), unless such arequirement is included as a part of themine ventilation plan.

MSHA is aware that through advancesin technology it may be feasible tocontinuously monitor air quantity andvelocity, and spray water flow rate andpressure. Continuous monitoring offersthe potential to further improve minerprotection by providing real-time dataon the performance and condition of

key dust control measures. Thisinformation can be used to give earlywarnings of deteriorating dust controls,allowing corrective action to be takenbefore the dust control system fails toprotect miners from excessive dustlevels. Although continuous monitoringwill eliminate the need for periodicphysical measurements to verify properoperation of some dust controls, visualobservation of other controls will still benecessary. Among these are the numberand location of operating water sprays,their general condition and orientation,the section ventilation setup and controldevice placement, the check forexcessive leakage in the water deliverysystem, and other control measureswhere performance and operatingcondition can only be assessed visually.

One commenter suggested that MSHAnot permit the use of continuousmonitoring in lieu of physical checksbecause technology to permit suchmonitoring is not as yet available. Thefinal rule is intended to be sufficientlyflexible to permit the use of newtechnology, such as continuousmonitoring and sensing devices, andalso to encourage the introduction ofsuch modern equipment. The final ruledoes not require the physicalmeasurement of the air velocity andquantity, water pressure and flow ratesif continuous monitoring of the dustcontrol parameters is used and indicatesthat the dust controls are functioningproperly.

The on-shift examination of the dustcontrols is to be completed under thedirection of a person who has beendesignated by the operator. Theproposal would have required that acertified person conduct theexamination. One commenter objectedto this approach, suggesting that thecompletion of this examination wouldrequire considerable time and that amore thorough examination could beaccomplished by a person(s) familiarwith the equipment and the dust controlmeasures being utilized. Thiscommenter recommended that MSHAremove the word ‘‘certified’’, thuspermitting the examination to beconducted by persons other thancertified persons. A second commenterargued that the examination should beconducted by a single individualbecause other persons may be assignedto a section who are not familiar withthe requirements of the mine ventilationplan for that section.

The final rule deletes the word‘‘certified,’’ permitting on-shiftexaminations of dust controls to beconducted by one or more persons whoare not certified individuals. However,the examination must still be conducted

under the direction of a persondesignated by the operator and as setout in paragraph (g)(2), a certifiedperson must certify that the examinationhas been completed. MSHA wouldexpect that the person directing thisexamination would be present at the siteof the examination while theexamination is conducted.

Another commenter recommendedthat the final rule not specify themeasurements that are to be made needduring the on-shift examination of dustcontrols, and that the standard berewritten to require such anexamination be sufficient to assurecompliance with the respirable dustparameters specified in the mineventilation plan. Because it is possibleto identify specifically some of theparameters that must be measured in allinstances the suggestion of thecommenter has not been adopted. Byidentifying these parameters in the finalrule, misunderstandings over whether aplan specification is for dust control ormethane control, for example, can beeliminated.

As proposed, paragraph (a)(2) wouldhave required that the respirable dustcontrol portion of the examination bemade at or near the beginning of theshift and before production begins on asection. One commenter suggested thatsuch a requirement would eliminate thecommon practice of changing shifts onthe section without an interruption inproduction. MSHA recognizes thatchanging crews without an interruptionin production has become a commonpractice in some areas and does notintend that this practice be changed bythis rule. The final rule has revised theproposal so that when a shift change isaccomplished without an interruptionin production on a section, the requiredexamination may be made any timewithin 1 hour of the shift change. Inthose instances when there is aninterruption in production during a shiftchange, the final rule requires that theon-shift examination of respirable dustcontrols be made before productionbegins on a section. The proposedwording ‘‘at or near the beginning of theshift’’ has not been included in the finalrule in recognition of the fact thatproduction on a section could bedelayed and not begun until well afterthe beginning of the shift. Because thepurpose of the standard is to assure thatdust exposures are controlled duringmining, the on-shift examination mustbe conducted prior to the beginning ofproduction in order to be most effective.

Other commenters objected toexamining respirable dust controlparameters for various reasons. Somecommenters stated that operators are


required to comply with therequirements of the mine ventilationplan relative to dust control and aseparate requirement is not needed. Themeasurements specified in the final ruleare a practical way to providereasonable assurance that miners are notbeing exposed to unhealthy levels ofrespirable dust. The purpose of thesechecks is not to restate the requirementsfor compliance with the mine’sventilation plan. Instead, as discussedabove, the final rule is intended to bringneeded attention to the properfunctioning of dust controls beforeproduction begins.

Other commenters expressed theopinion that coal production should notbe delayed until after the completion ofthe examination of dust controls.According to these commenters, thisexamination will take the certifiedperson away from other examinationsthat must be completed to assure safety.As explained previously, the final rulehas been revised to permit the changingof crews without an interruption inproduction. The completion of the on-shift examination of dust controlparameters can be postponed for up to1 hour when crews are switched out atthe face. Additionally, the final rule hasbeen revised to permit the examinationof dust control parameters to beperformed by a person(s) other than acertified person and to simply requirethe certified person to certify that theexamination was completed. Theserevisions substantially reduce any delayin production that could have resultedunder the rule as proposed.

Another commenter objected to therequirements of paragraph (a)(2) statingthat examination of dust controls isunnecessary because all personnel arerequired to be trained in therequirements of all approved mine plansincluding the mine ventilation plan, andmany of the required mine ventilationplan parameters are checked during thepre-shift examination. The commenterstated further that other parameters,such as number of water sprays andpressure, are checked by the equipmentoperators during the pre-operationalinspection. In the opinion of thecommenter, the proposed examinationof dust control parameters is redundantand unnecessary.

The requirements of paragraph (a)(2)are not redundant with existingstandards. There is no requirement fora pre-operational inspection of dustcontrols. For the reasons discussedabove, MSHA considers examination ofdust controls for proper functioning tobe an important practical measure forprotecting miners’’ health. To the extentthat these checks are currently being

made by some operators, together withthe flexibility of the final rule, theburden of making these checks isminimized.

The final rule requires in paragraph(a)(2) that deficiencies found during theon-shift examination of dust controls becorrected before production begins, orwhen crews are changed without aninterruption in production, beforeproduction continues. The proposalwould have required that deficiencies inthe controls be corrected immediately.However, the final rule revises theproposal in response to one commenterwho pointed out that the correction ofdeficiencies is important prior toproduction, in view of the purpose ofthe rule.

Another commenter suggested thatthe examination of dust controls beconducted after production begins so asto be more representative of productionconditions. In contrast, anothercommenter observed that if the requireddust control parameters are not beingmet before production is begun, it isunlikely that they will be met afterproduction is started. This commentersuggested multiple examinations, onebefore production begins and one atsome later time during the shift. MSHAagrees that if dust control measures aredeficient before production begins it isunlikely that they will be corrected laterin the shift. Therefore the final rulerequires the on-shift examination of thedust control measures prior to thebeginning of production. The final rule,however, does not include therecommendation for an additionalexamination of dust control measures.

Paragraphs (c)(1) and (c)(2) requirecertified persons conducting on-shiftexaminations to take air measurementsat the same locations where airmeasurements are required during thepreshift examination. This includesareas where mechanized miningequipment, including longwall orshortwall mining equipment, is beinginstalled or removed. Reduced volumeor velocity of air during the shift cancontribute to increased levels ofrespirable dust, methane accumulations,or oxygen-deficient atmospheres.Checking the mine’s ventilation systemverifies that changes in the mineventilation system due to theproduction process have not occurred.

The final rule removes the word‘‘working’’ from paragraph (c)(1) toassure that the application of thestandard would extend to all sections,consistent with paragraph (a). Many ofthe activities to which miners areassigned are on sections not normallythought of as ‘‘working sections,’’ a termassociated with coal production. For

purposes of § 75.362, a section in themine is considered to be the area inbythe loading point; or, in the case of theinstallation of mechanized miningequipment, inby the proposed loadingpoint; or, in the case of the removal ofmechanized mining equipment, inby thelocation of the last established loadingpoint. The final rule requires inparagraphs (a)(1), (c)(1), and (c)(2) thatthe certified person conducting the on-shift examination examine the sectionin much the same way as it would beexamined during a coal producing shift,including checking for hazardousconditions, testing for methane andoxygen deficiency, determining if the airis moving in its proper direction, andmeasuring the volume of air in the lastopen crosscut or in the intake oflongwalls or shortwalls, as appropriate.

Some commenters objected to thisprovision stating that there is littlesafety benefit to requiring on-shiftexaminations on sections other thanworking sections where coal is beingproduced. The final rule does not limiton-shift examinations to ‘‘workingsections’’ but includes other areas wherepersons are working. Hazards similar tothose that develop on a coal producingsection can also develop during a shifton sections that are not producing, butwhere personnel are assigned to work.

Paragraph (d)(1)(i) requires that at thestart of each shift, before electricallyoperated equipment is energized, aqualified person test for methane at eachworking place. One commentersuggested that the existing standard issufficient because quite often in today’smining practices equipment is alreadyenergized at the start of the shift sinceone equipment operator takes over fromthe previous operator and examinationsfor methane have been performed every20 minutes as required by§ 75.362(d)(1)(ii). MSHA does not agreethat the existing standard is sufficientfor a number of reasons. First, althoughthe commenter is correct in stating thatswitching operators while theequipment remains energized is arelatively common practice it is not auniversal practice. In mines whereequipment is deenergized betweenshifts, the final rule provides for a testfor methane in each working place priorto the equipment being energized. Onsections in mines where equipmentoperators are switched while equipmentremains energized, MSHA wouldconsider a methane test performedduring the previous 20 minutes underparagraph (d)(1)(iii) as sufficient tocomply with the methane testrequirement of paragraph (d)(1)(i) forthe working place where mining istaking place. However, paragraph


(d)(1)(i) also requires that methane testsbe made in other working places on thesection not only in the working placewhere the equipment is being operated.

The final rule requires in paragraph(d)(1)(iii) that methane tests be mademore frequently than 20 minutes ifrequired in the approved mineventilation plan at specific locations,during the operation of equipment inthe working place. One commenterobjected to this requirement expressingthe opinion that the standard does notidentify situations in which morefrequent methane tests would bewarranted and, therefore, operatorscould be faced with a requirement toconduct additional methane tests whichare unwarranted and would result in themisallocation of safety resources. Thefinal rule is intended to addresssituations such as an abnormally highmethane liberation rate in a mine or anarea of a mine that would warrant morefrequent testing for methane. Like theexisting standard the final rule requiresthis test to be made by a qualifiedperson, not a certified person, thus inmost cases the person who makes thetest will be the machine operator. As aresult, this test will not require thatother safety-related activities be stoppedto make a test for methane.

Under the existing rule, methane testsrequired by paragraph (d)(1) were to bemade at the last permanent roof supportunless the mine ventilation planrequired that they be made closer to theface using extendable probes. Paragraph(d)(2) of the final rule revises thisstandard and requires that the methanetests specified in paragraphs (d)(1)(i)through (d)(1)(iii) be made at the facefrom under permanent roof support,using extendable probes or other means.Like the existing standard, paragraph(d)(2) requires that for longwall andshortwall mining systems, the tests areto be made at the cutting head. Whenmining has been stopped for more than20 minutes, methane tests must be madeprior to the start up of the equipment.

During informational meetingsfollowing the publishing of the existingstandard, it became apparent that a largesegment of the mining community feltthat methane tests should be made asclose to the working face as practicablewithout exposing miners to unsafeconditions. MSHA agrees that propertesting for methane at the face isessential for safe mining operations. Theneed for making methane tests at theface has been demonstrated byresearchers and engineers from the U.S.Bureau of Mines and MSHA throughwork performed over the last 25 years.This work documents that in a workingplace the concentrations near the face

are considerably higher than other areasin the working place. For example,Luxner, in Bureau of Mines Report ofInvestigation 7223, ‘‘Face Ventilation inUnderground Bituminous Coal Mines,’’published in 1969, reported methaneconcentration in excess of 5 percent asfar back as 15 feet using both blowingand exhaust ventilation systems with acurtain-to-face distance of 20 feet. Theconcentration outby this location asreported by Luxner was between zeroand 1 percent. Later, Haney, et al., alsoshowed lesser concentrations ofmethane further from the face usingvarious types of assisted ventilationsystems.

A speaker at one of the publichearings on the proposal suggested thattests should be made at the last row ofbolts and if 0.2 percent of methane isfound at that location, a probe should beused to test at the face. The final ruledoes not adopt this recommendationbecause MSHA is unaware of any teststhat relate the concentration of methaneat the face with the concentration at thelast row of bolts. Based on currentknowledge, it is doubtful that such adirect correlation could be madebecause of the number of variablesinvolved.

A recurring comment concerningtaking methane tests at the face with aprobe was that such a requirement willlead to an increase in the number ofback injuries among miners. However,other commenters supported therequirement and stated that probes aslong as 40 feet are currently being usedin some areas of the country. Minerswith experience in using these probestestified at the rulemaking hearings thatalthough the long probes can at times bedifficult to use, they are being used andare providing measurements of methaneat the face in mines operating in coalseams as low as 37 inches.

The possibility of an increase in thenumber of back injuries is of seriousconcern to MSHA. However, afterreviewing all of the written commentsand testimony taken during publichearings, particularly that of minershaving experience with the use ofprobes, MSHA is persuaded that this isa reasonable approach and will achievethe desired safety results without unduerisk of back injuries.

Several commenters suggested that inlieu of requiring methane tests at theface, MSHA should permit the use ofthe methane monitor to satisfy therequirement. In making thisrecommendation, one commentersuggested that the methane monitorsshould not be required to be installed onface equipment if they cannot also beused to test for methane in unsupported

faces. Methane monitors have provenreliable over the years and provide asecond level of protection againstmethane ignitions. Methane monitorsprovide for methane detection at a fixedlocation while the use of a methanedetector with a probe permits methanemeasurements to be made at variouslocations in the face area.

Historically, machine-mountedmethane monitors have been used as abackup for the other required tests. Thisconcept was exactly what Congressrecognized in § 303(l) of the Coal MineHealth and Safety Act of 1969 (CoalAct). Discussing this provision, theconference managers noted ‘‘...themethane monitor is an additionalbackup device for detecting methaneand should not be construed as asubstitute for the other tests and testingdevices required in this title fordetecting and controlling methane.’’H.R. Conf. Rep. No. 91–761, 91st Cong.,1st Sess. 80 (1969).

The final rule does not adopt thesuggestion of commenters that methanemonitors be accepted in lieu of themethane tests required by paragraph(d)(2).

Paragraph (g)(1) adopts the languageof proposed paragraph (g) and requiresthat the person making the on-shiftexamination in belt haulage entriescertify by initials, date, and time thatthe examination was made at enoughlocations to show that the entire areahas been examined. As explained in thepreamble to the proposal, the existingrule does not require certification thatexaminations were conducted in beltconveyor entries. Comments receivedexpressed the view that withoutcertification, no mechanism exists toverify that examinations wereconducted in belt conveyor entries.Other commenters questioned whatMSHA meant by ‘‘enough locations.’’MSHA agrees with the commenter thatthe certification requirement should beadded to the rule to provide a means toverify that the examination has takenplace. With respect to the locationswhere the certification should be made,this certification process is a commonpractice in the industry and is requiredby several state regulations. Thelocations where certification would beexpected to be kept are no different thanthose which were required for manyyears under the previous MSHAregulation and which have beencommonly accepted in the industry.Paragraph (g)(2) is a new requirementrelating to the certification of theexamination of respirable dust controlparameters. Under (g)(2), the personmaking the on-shift examination toassure compliance with the respirable


dust control parameters specified in themine ventilation plan must certify byinitials, date, and time that theexamination was made.

Section 75.363 Hazardous Conditions;Posting, Correcting, and Recording

Section 75.363 is a new sectionrequiring the posting, correcting andrecording of hazardous conditions. Theposting of hazardous conditions againstentry is a time tested method forpreventing accidents. Examiners, uponfinding a hazardous condition, erect‘‘danger boards’’ to alert personstraveling in the area of the presence ofthe hazard. In this manner, miners areprevented from inadvertently enteringan area where a hazard exists. Section75.363 requires that hazardousconditions be posted and access to thearea be limited; that the hazardousconditions be corrected immediately orremain posted; and, that a record bemade and maintained of the hazardouscondition and the action taken to correctthe condition. Records of the hazardsand the actions required to correct thehazards provide valuable safetyinformation about conditions in themine and the effectiveness of correctivemeasures.

MSHA’s final rule modifies theproposal in several ways. The final ruledeletes the phrase ‘‘or reported to’’ thatappeared in the first sentence ofproposed § 75.363(a) and deletes therequirement for countersigning by asecond level official. It specifies that,except for preshift or preshift typeexaminations, hazardous conditionsshall be corrected immediately orposted until the conditions arecorrected. The final rule allows forcountersigning by an official equivalentto the mine foreman and provides forstorage of records in either a securebook or in electronic media which is notsusceptible to alteration.

It is essential that all hazardousconditions, regardless of when detectedor by whom, be adequately addressed.Commenters suggested that theproposed standard be deleted because,in their opinion, other standardsprovide adequate coverage. Onecommenter interpreted the proposedstandard as being directed at only thosehazards found during the on-shiftexamination and supplementalexaminations, because hazardousconditions found during the preshiftand weekly are excluded from thestandard. This commenterrecommended rewriting therequirements for the on-shift andsupplemental examinations to reflectthe needed changes.

Section 75.363 is not directed onlytoward hazardous conditions foundduring examinations. Hazardousconditions occur and are found at timesduring the shift when examinations arenot being made. Under the final rule,these hazardous conditions would alsorequire posting, correction, andrecording when found by the mineforeman or equivalent mine official,assistants to the mine foreman orequivalent mine official, or othercertified persons designated by theoperator to conduct examinations.

One commenter questioned whetherthe proposed standard was intended toassign new duties to the mine foremanand assistant mine foremen. The finalrule does not impose additionalresponsibilities on the mine foremanand assistant mine foremen. However,these individuals are certified androutinely travel throughout the mine forpurposes other than makingexaminations. The standard requiresthat hazardous conditions found by themine foreman, assistant mine foreman,or equivalent mine officials, be treatedthe same as hazardous conditions foundby other certified persons who havebeen designated to conductexaminations. That is, the hazardousconditions are to be appropriatelyposted, corrected, and recorded. Theterm ‘‘equivalent mine officials’’ hasbeen added in response to commenterswho suggested that the term ‘‘mineforeman’’ is no longer used at all mines.

Under paragraph (a) any hazardouscondition found by the mine foreman orequivalent mine official, assistants tothe mine foreman or equivalent mineofficial, or other certified personsdesignated by the operator to conductexaminations is to be posted with aconspicuous danger sign. The postingrequirements of this section apply toevery hazardous condition regardless ofwhen it is found. Under the proposal,hazardous conditions reported to themine foreman, assistants to the mineforeman or other certified personsdesignated by the operator to conductexaminations would have requiredposting. Commenters suggested thatrequiring hazardous conditions‘‘reported to’’ these individuals wouldeliminate the judgement of the personsresponsible for making decisions aboutwhether or not a hazardous conditionexists. One commenter suggested thatthe requirement, as proposed, couldundermine the integrity of the certifiedperson. The final rule is revised torequire that hazardous conditions foundby the mine foreman or equivalent mineofficial, assistant mine foreman orequivalent mine official, or othercertified persons designated by the

operator for the purpose of conductingexaminations shall be posted with aconspicuous danger sign and shall becorrected immediately or remain posted.MSHA would expect that when ahazardous condition is reported to thesecertified persons, that the measuresnecessary to evaluate the situation and,if necessary, to comply with theprovisions of this section would betaken.

One commenter suggested that theproposed requirement that all hazardousconditions be corrected ‘‘immediately’’would diminish safety because minerscould be exposed to hazardsunnecessarily. The commenter offeredas an example an area of bad roof in a‘‘remote, unused crosscut’’ andsuggested that in this case posting of thearea against entry would be sufficient.MSHA recognizes that there areinstances, such as the examplepresented by the commenter, wheresafety is best served by simply postingthe area against entry. This has longbeen the practice in the industry and thefinal rule does not prevent this fromcontinuing. In these cases, the correctiveaction required to prevent injury is topreclude persons from entering the area.The proposal would have required thatthe hazardous condition be correctedimmediately and that the area remainposted until the hazardous condition iscorrected. To reflect therecommendation of the commenter, thefinal rule requires that the hazardouscondition be corrected immediately orthat the area remain posted until thehazardous condition is corrected. TheAgency recognizes that in someinstances posting the area against entryis the corrective action.

The requirement that the hazardousconditions be corrected immediatelydoes not necessarily require correctionby the certified examiner finding thecondition. To do so could delay thecompletion of the examination. Rather,the final rule requires that thehazardous condition be correctedfollowing the reporting of the conditionby the examiner to the appropriate mineofficial. Common sense and soundjudgement should enter into thedecisions as to when hazardousconditions are corrected. Posting of thearea where the hazardous conditionexists in order to prevent entry is to beaccomplished by the certified personfinding the hazardous condition.

One commenter questioned whetherproposed paragraph (a) would requirethe hazardous condition itself be posted.The posting of the area, as opposed tothe hazardous condition itself, would,in most cases, be more effective and asafer practice. For instance, if a section


of bad roof is detected, it would be inthe best interest of safety to mark thearea or perimeter of the area of bad roofinstead of the roof itself. The ‘‘danger’’sign would be placed at a locationwhere anyone entering the area of thehazardous condition would pass so thatpersons approaching the area would beexpected to see the ‘‘danger’’ sign. Thearea would remain posted until thehazardous conditions are corrected. Theposting of areas where hazardousconditions exist to alert persons is along-standing accepted safety practicein the mining community.

Paragraph (a) requires that once anarea is posted due to a hazardouscondition, only persons designated bythe operator to correct or evaluate thecondition may enter the posted area.Additionally, if the hazardous conditioncreates an imminent danger, everyonemust be withdrawn from the affectedarea to a safe area until the condition iscorrected. Persons referred to in section104(c) of the Act are permitted to enterin the area.

One commenter suggested that therepresentative of the miners bepermitted to enter an area which hasbeen posted with a ‘‘danger’’ in order toevaluate the condition. The final rulefollows the statutory provision in§ 104(c) of the Mine Act. Thislongstanding requirement provides thatonly persons designated by the operatorto correct or evaluate the hazardouscondition may enter such posted areas.With respect to the representative ofminers, § 104(c)(3) provides that therepresentative of the miners in suchmine who is, in the judgment of theoperator or an authorized representativeof the Secretary, qualified to make mineexaminations or who is accompanied bysuch a person and whose presence insuch area is necessary for theinvestigation of the hazardous conditionmay enter the area.

Paragraph (b) requires that a record ofhazardous conditions be made by theend of the shift on which the conditionwas found. This record is required to bemaintained on the surface and mustinclude the nature and location of thehazardous condition and the correctiveaction taken. A record of all hazardsfound, as well as the required correctiveaction, serves as a history of the typesof conditions that can be expected in themine. When the records are properlycompleted and reviewed, minemanagement can use them to determineif the same hazardous conditions arerecurring and if the corrective actionbeing taken is effective. No record isrequired on any shift on which nohazardous conditions are found.Paragraph (b) excludes hazardous

conditions found during the preshiftand weekly examinations because theseexaminations have separate recordkeeping requirements.

Commenters recommended rewordingthe standard to eliminate the provisionsthat no record is required on any shifton which no hazardous condition isfound and that the corrective actiontaken must also be recorded. Thesesuggestions were offered to clarify thestandard. MSHA believes that deletingthese requirements would not clarify therule and the suggestions are not adoptedin the final rule.

Paragraph (c) requires that a record bemade either by the certified person whoconducted the examination or by aperson designated by the operator. Aswith other records required by thissubpart, when the record is made by adesignated person other than thecertified person making theexamination, the person making therecord need not be certified. If therecord is made by a person designatedby the operator, the certified personmust verify the record by initials anddate. MSHA did not receive anycomments objecting to this part of thestandard. Like the other recordkeepingrequirements in the proposal, proposedparagraph (c) would have required thatthe record be made in a state-approvedbook or a bound book with sequentialmachine-numbered pages. Additionally,the proposal would have requiredcountersigning by both the mineforeman and the superintendent orequivalent individual to whom the mineforeman reports. The final rule requiresthat the records of hazardous conditionsmust be kept in either secure books thatare not susceptible to alteration, orelectronically in a computer system soas to be secure and not susceptible toalteration. A detailed discussion ofrecord books and the use of computersto maintain records can be found in theGeneral Discussion of this preamble.

A variety of comments were receivedregarding the countersigning of therecord by the mine foreman, and thetime permitted for countersigning. Thefinal rule adopts the proposal that themine foreman or equivalent mineofficial must countersign the record ofhazardous conditions by the end of themine foreman’s next regularlyscheduled working shift. The mineforeman is responsible for the day-to-day operation of the mine. It is essentialfor the health and safety of the minersthat the mine foreman be fully aware ofthe information contained in this recordso as to be able to allocate resources tocorrect safety problems as they develop.Allowing until the end of the mineforeman’s next regularly scheduled

working shift to countersign the recordsassures that the mine foreman is awareof hazardous conditions in sufficienttime to initiate corrective actions.

Some commenters suggested that thetime for countersigning is unnecessarilylong, and that the final rule shouldrequire daily countersigning by themine foreman. The rulemaking recorddoes not show, however, that the timeset by the final rule would exposeminers to safety or health risks. Also,hazardous conditions must be correctedimmediately or the area must remainposted until the condition is corrected.

Numerous comments were receivedregarding the requirement of theproposal for second level countersigningof the preshift examination record bythe mine superintendent, mine manager,or other mine official to whom the mineforeman is directly accountable within 2scheduled production days after thecountersigning by the mine foreman.The final rule does not retain thisproposed requirement. A detaileddiscussion of the subject of second levelcountersigning can be found in theGeneral Discussion section of thispreamble.

As proposed, paragraph (d) of thefinal rule requires that the recordsrequired by § 75.363 be maintained at asurface location at the mine for one yearand be made available for inspection byauthorized representatives of theSecretary and the representative ofminers. Comments on this requirementwere generally favorable. A discussionof comments concerning the use ofcomputers to maintain records can befound in the General Discussion of thispreamble.

Section 75.364 Weekly ExaminationThe weekly examination is directed at

hazards that develop in the more remoteand less frequently visited areas of amine. These areas include: worked-outareas where pillars have not beenremoved, bleeder entries used toventilate worked-out areas where pillarshave been removed and, some mainintake and return air courses. Over thecourse of time, hazards such as methaneaccumulations and obstructions toventilation can develop in these areasand can result in an explosion or loss ofventilation if not discovered andcorrected. Because of the confinednature of the underground miningenvironment, loss of life can result inother areas of the mine outside theimmediate location of the hazard. Theweekly examination assures that thesehazards are located and corrected.

Generally, § 75.364 requires anexamination in unsealed worked-outareas that have not been pillared; travel


in bleeder entries and the performanceof appropriate measurements in theseentries and; a check for hazardousconditions in return and intake aircourses, in each longwall travelway, ateach seal along return and bleeder aircourses and each seal along intake aircourses not otherwise examined, in eachescapeway, and each working sectionthat has not been preshift examinedduring the previous 7 days.

The final rule modifies existing§ 75.364 (a), (b), and (h). It adoptsseveral proposed changes to § 75.364and modifies or rejects other proposedchanges.

Paragraph (a) specifies weeklyexamination requirements in unsealedworked-out areas where no pillars havebeen recovered as well as in bleedersystems. The final rule requires thatunpillared worked-out areas and bleedersystems be physically examined on aweekly basis and specifies the tests andmeasurements to be performed by theexaminer. The final rule identifies twoseparate locations within nonpillaredareas and bleeder systems wheremeasurements may be required. First,measurement points must be includedin the mine ventilation plan to identifythe locations within unpillared worked-out areas and bleeder systems whereexaminers will conduct airmeasurements and tests, the results ofwhich are to be recorded. Thesemeasurement points are not in lieu oftraveling the system, but rather are thelocations where the examiner willperform air quantity and quality testsand measurements to determine theeffectiveness of ventilation. Thesepoints are tracking and evaluation toolsto assure adequate ventilation and toidentify developing trends in ventilationor air quality which may requireattention.

Second, evaluation points may beapproved in the mine ventilation planon a case-by-case basis as providedunder (a)(1) and by (a)(2)(iv). Theseevaluation points may be used in lieu ofphysical examinations. Evaluationpoints may only be approved in lieu oftravel if the evaluation points are fullyadequate to demonstrate that the area isventilated. These provisions arediscussed below.

The final rule clarifies thatmeasurement points for weeklyexaminations must be specified in themine ventilation plan for bothunpillared and pillared worked-outareas described in (a)(1) and (a)(2)(iii),respectively. These measurement pointsare distinct from the evaluation pointswhich may be approved in lieu of aphysical examination under somecircumstances. As mentioned above,

evaluation points are governed by (a)(1)for unpillared worked-out areas, and by(a)(2)(iv) for pillared worked-out areasventilated by bleeder systems. Section75.371(z) of the final rule refers to theserequirements for both measurementpoints and evaluation points. Themeasurement points and evaluationpoints may be either in the body of themine ventilation plan or may be shownon the 75.372 map. In either case, thelocations are subject to approval byMSHA.

Under paragraph (a)(1), at least every7 days a certified person must examineunsealed worked-out areas where nopillars have been recovered by travelingto the area of deepest penetration;measuring methane and oxygenconcentrations and air quantities andmaking tests to determine if the air ismoving in its proper direction in theareas. The locations of measurementpoints where tests and measurementswill be performed must be included inthe mine ventilation plan and must beadequate in number and location toassure ventilation and air quality in thearea. Air quantity measurements mustbe made where the air enters and leavesthe worked-out areas. Sufficientmethane and oxygen measurementsmust be made to assure the air qualityin the worked-out areas. An alternativemethod of evaluating the ventilation ofthe areas may be approved in the mineventilation plan.

Under paragraph (a)(1), in addition tomeasuring oxygen and methaneconcentrations and testing for proper airdirection, air quantities must also bedetermined. Air quantity measurementsare required where air enters and leavesthe worked-out area. The final rule alsorequires that a sufficient number ofmeasurement points must be includedin the mine ventilation plan to assureappropriate ventilation and air qualityin the area.

The changes to paragraph (a)(1) are inresponse to comments and MSHAexperience with weekly examinations.Currently some examiners are simplytraveling to the point of deepestpenetration while conducting few if anytests or air measurements within thesystem. The full benefit of an examinertraveling to the point of deepestpenetration is lost if the examiner doesnot conduct air quantity and qualitymeasurements at key locations.

The results of these measurements areimportant in assessing the effectivenessof ventilation. In addition, trends ineither air quantity or quality can revealdeveloping problems which can becorrected in the earliest stages.

One commenter suggested that theentire perimeter of worked-out areas

should be physically examined to allpoints of deepest penetration. Thecommenter suggested that the face ofeach entry or room should be examinedat its point of deepest penetration.MSHA agrees that travel to a singlepoint of deepest penetration within anarea may sometimes be inadequate tofully demonstrate effective ventilationof a worked-out area. The final ruleaddresses this issue by requiring thatmeasurement points be established inthe mine ventilation plan.

Paragraphs (a)(2) (i) through (iv) of thefinal rule retain the requirement that atleast every 7 days a certified personmust evaluate the effectiveness ofbleeder systems used under § 75.334 (b)and (c). Like the proposal, the final rulealso specifies tests and locations for aneffective examination. One commenternoted that mine examinations aresometimes ineffective and supported theproposed additional specificity in therule, requiring air measurements andtests at key locations or measurementpoints within worked-out areas.Established locations where examinerswill conduct air measurement and testswill help assure effective examinationsand provide quantitative results to theoperator. The final rule requires that themine ventilation plan includemeasurement points within worked-outareas and paragraph (h) requires that theresults be recorded.

Paragraph (a)(2)(ii) requires thatmeasurements of methane and oxygenconcentrations be made, air quantity bemeasured, and a test performed todetermine if the air is moving in itsproper direction at a point immediatelybefore the air enters a return split of air.A commenter supported the proposedair measurements where air enters andleaves worked-out areas and correctlynoted that such measurements wouldreveal some types of ventilationproblems. In a special case, such aswhere it may not be possible to measureintake air, paragraph (a)(2)(iv) permitsan alternate method of evaluation to beused when approved in the mine’sventilation plan.

Another potential hazard exists whenmultiple intake openings lead into suchan area, if passing intake air entersupstream openings of the worked-outarea and reenters the intake fromdownstream openings. The final rulealso requires that air quantitymeasurements be made where air entersand leaves worked-out areas.Measurements made where air entersand exits the area will alert theexaminer and operator to airflowchanges or imbalances which indicate apotentially dangerous ventilationproblem. The specification of


measurement points within worked-outareas will also assure that short circuitshave not interrupted ventilation.

One commenter stated that thestandard should fully delineate allaspects of the weekly examination byspecifying that the examination includeroof and ribs, ventilation controls, wateraccumulations, etc. Although MSHAagrees that these and other conditionsfall within the purview of the weeklyexamination, the final rule does notattempt to provide an exhaustive list ofwhat is to be covered in a weeklyexamination. Examinations areperformed by persons trained andcertified as able to make the requiredexaminations. Such certified personscan be expected to give proper attentionto basic safety considerations.

Paragraph (a)(2)(iii) requires that atleast one entry of each set of bleederentries used as part of a bleeder systemunder § 75.334 must be traveled in itsentirety. Under the final rule,measurements of methane and oxygenconcentrations and air quantities arerequired to be made during theexamination. Also, a test to determine ifthe air is moving in its proper directionmust be made at locations ormeasurement points, specified in themine’s ventilation plan. Themeasurements and tests provide theinformation necessary to determine theeffectiveness of the bleeder system.

One commenter believed that theproposal would require each paralleland common bleeder entry of a set to betraveled. The final rule is intended tosimplify the examination and would,under the circumstances described bythe commenter, require only one entryof a set of common entries to beexamined in a bleeder system. Also,similar to the requirements for travelingintake and return air courses, thisrequirement should not be interpretedto require the examiner to stay in oneentry. For example, if the examinerdesires to ‘‘zig zag’’ between entrieswhile traveling in a multi-entry bleedersystem, this would be acceptable underthe regulation provided tests andmeasurements are made at theappropriate locations.

Paragraph (a)(2)(iv) provides that, inlieu of the requirements of (i) through(iii), alternative methods of evaluationmay be specified in the mine ventilationplan provided that the alternativemethod results in proper evaluation ofthe effectiveness of the bleeder system.One commenter cited several explosionsthat were related to bleeder systemdeficiencies and linked poor design andinadequate maintenance with theprovision allowing examination atevaluation points in lieu of traveling the

area in its entirety. The thrust of thecommenter’s argument was that aninflexible standard requiring either fulltravel of a bleeder system or sealing ofthe entire area would result in superiordesigns and improved maintenance.While MSHA agrees with thecommenter’s ultimate objective ofensuring effective ventilation of bleedersystems and worked-out areas, MSHAdoes not agree that elimination of anyflexibility within the standard wouldresult in infallible designs. Sinceapproval of evaluation points is onlygranted in cases where adequateventilation can be determined throughevaluation, MSHA believes thatretaining flexibility to review individualcases is an appropriate method andresults in proper evaluation of theeffectiveness of the bleeder system.

Paragraph (h) of the final rule governsrecordkeeping requirements for weeklyexaminations. The final ruleincorporates several revisions based onrecommendations submitted bycommenters. The final rule requires thatat the completion of any shift duringwhich a portion of a weeklyexamination is conducted, a record ofthe results be made. This record mustinclude any hazardous conditions foundduring the examination and theirlocations, the corrective actions taken,and the results and location of air andmethane measurements. The recordmust be made by the person making theweekly examination or a persondesignated by the operator.

The final rule includes a revisionrequiring that the results of methanetests must be recorded as the percentageof methane measured by the examiner.Previously, terms such as ‘‘ok,’’ ‘‘low,’’or ‘‘trace’’ were entered in record booksas test results. The final rule clarifiesthat such qualitative terms are notacceptable when examinationrequirements specify the measurementof air quantity or methane levels as suchentries provide little useful information.

The final rule requires that if therecord is made by a person other thanthe examiner, the examiner must verifythe record by initials and date by or atthe end of the shift for which theexamination was made. As with otherrecords required by this rule, therecords of weekly examinations may bekept either in secure books that are notsusceptible to alteration, orelectronically in a computer system soas to be secure and not susceptible toalteration. A detailed discussion ofrecord books and the use of computersto maintain records can be found in theGeneral Discussion of this preamble.

Commenters suggested that the finalrule only require the examiner to record

uncorrected hazardous conditions.MSHA is sensitive to minimizingrecordkeeping requirements and, forexample, the final rule requires onlyuncorrected defects found during thefan examination to be recorded.However, the weekly examinationrecord serves as a history of the types ofconditions that can be expected in themine. When the records are properlycompleted and reviewed, managementcan use them to determine if the samehazardous conditions are occurring andif the corrective action being taken iseffective. Additionally, this record canpermit mine management, therepresentative of the Secretary, and therepresentative of miners to better focustheir attention during examinations andinspections. The final rule adopts theproposal and requires the examiner torecord all hazardous conditions foundand the action taken to correct thehazardous condition.

A variety of comments were receivedregarding the countersigning of therecords of weekly examinations by themine foreman, and the time permittedfor countersigning. The final rule adoptsthe proposal that the mine foreman orequivalent mine official mustcountersign the record of the weeklyexamination by the end of the mineforeman’s next regularly scheduledworking shift. The mine foreman is ina key position of responsibility relativeto the day-to-day operation of the mine.It is essential for the health and safetyof the miners that the mine foreman befully aware of the information containedin the preshift examination reports so asto be able to allocate resources to correctsafety problems as they develop.Allowing until the end of the mineforeman’s next regularly scheduledworking shift to countersign the reportsassures that the mine foreman is awareof the results on a regular and timelybasis.

Numerous comments were receivedregarding the requirement of theproposal for second level countersigningof the weekly examination record by themine superintendent, mine manager, orother mine official to whom the mineforeman is directly accountable. A fulldiscussion of second levelcountersigning can be found in theGeneral Discussion section of thispreamble.

Paragraph (h) of the final rule alsocontains revisions to the existing rule toallow for electronic storage of records.Paragraph (i) requires that the recordsrequired by § 75.364 be maintained at asurface location at the mine for one yearand be made available for inspection byauthorized representatives of theSecretary and the representatives of


miners. A discussion of commentsconcerning the use of computers tomaintain records can be found in theGeneral Discussion of this preamble.

Under the final rule, the record ofweekly examinations must becountersigned by the mine foreman orequivalent mine official by the end ofthe mine foreman’s next regularlyscheduled working shift. Based oncomments noting that traditional minemanagement structures have changes atsome operations, the final rule providesthat an official equivalent to mineforeman may countersign the records.The purpose of this change is to requirethat when a mine foreman is not presentin the mine’s management structure, anequivalent official must perform thisfunction. As with the existing standard,second level countersigning by the minesuperintendent is not required by thefinal rule.

The record of weekly examinationsmust be made in secure media notsusceptible to alteration. If records aremade electronically, they must beunalterable, shall capture dates andsignatures, must be accessible torepresentatives of the miners and theSecretary, and must be capable ofproducing printouts. Further discussionof both the issues of second levelcountersigning and acceptable recordbooks or electronic records can be foundin the general discussion section of thispreamble.

The proposal, at paragraph (b), wouldhave added a requirement that thecertified person examine fornoncompliance with mandatory safetyor health standards that could result ina hazardous condition. The proposaldrew considerable objection.Commenters objected to the unlimitedscope of the term ‘‘noncompliance,’’ thelegal propriety of recordingnoncompliance, and the additionalexamination time required to determinenoncompliance, the diversion of theexaminer’s attention away from keysafety conditions to minor complianceissues. Even so, another commentersupported the proposal as necessary,suggesting that the earlier rule wasintended to require operators to assurefull compliance through the requiredexaminations. The commenter correctlynoted that a requirement to examine forsafety and health violations was ineffect from 1970 until 1992 when it wasdeleted.

While the proposed standardappeared attractive in concept, themajority of comments received indicatethat the standard would result inconsiderable confusion. In addition, itwould be impractical to define andadequately limit the scope of the

requirement. Comments consistentlyindicated confusion andmisinterpretation of the proposal’sscope, offering a wide range ofinterpretations.

As discussed in the preamble to the1992 rule, most hazards are violations ofmandatory standards. Requiring theexaminer to look for all violationsregardless of whether they involve adistinct hazard could distract theexaminer from the more importantaspects of the examination. Despite anattempt in the proposal to limit thescope of the examination fornoncompliance to situations that,‘‘could result in a hazardous condition,’’commenters expressed a high level ofmisunderstanding. Although a similarrequirement existed between 1970 and1992, MSHA generally did not broadlyapply the standard. After considerationof all comments and a review of thehistory since the current standardbecame effective, MSHA concludes thatthe existing standard is appropriate andbest serves the objective of givingexaminers clear guidance for makingeffective examinations. Accordingly, theproposal for examinations to includenoncompliance with mandatory safetyand health standards is not adopted inthe final rule.

Paragraph (b)(7) has been added torequire that water pumps not examinedas part of a preshift examinationconducted during the previous 7 daysbe examined during the weeklyexamination. This modification is anoutgrowth of comments received inresponse to proposed § 75.360, whichwould have required examination ofcertain pumps. As discussed in thepreamble to § 75.360, one commenterpersuasively argued that all pumpsshould be examined. Pumps that are notpreshift examined under the final ruleare generally located in remote areas ofthe mine. These pumps areappropriately examined on a weeklybasis.

Section 75.370 Mine Ventilation Plan;Submission and Approval

Mine ventilation plans are a longrecognized means for addressing safetyand health issues that are mine specific.Individually tailored plans, with anucleus of commonly acceptedpractices, are an effective method ofregulating such complex matters asmine ventilation and roof control.Section 75.370 requires that each mineoperator develop and follow aventilation plan that is approved byMSHA and that is designed to controlmethane and respirable dust in themine. Section 75.370 further requiresthat the plan be suitable to the

conditions and mining system at themine. In addition, § 75.370 provides theprocedures for submittal, review andapproval of the plan to assure that theplan for each mine will address theconditions in that mine.

In this final rule, MSHA revises theexisting plan submission and approvalprocess to provide an increased role forthe representative of miners in the mineventilation plan approval process. Thisrevision is consistent with the statutorypurpose that miners play a role in safetyand health.

The final rule redesignates existingparagraphs (b)(1) through (f) as (c)(1)through (g), revises paragraphs (a)(3),(c)(1), and (f), and adds a new paragraph(b). The proposal would have modifiedthe existing rule by providing that therepresentative of miners would receivea copy of the proposed mine ventilationplan or proposed revisions at the timeof submittal to MSHA, and the approvedplan upon approval by MSHA. Theexisting rule provided that thesubmitted plan and the approved planwere to be made available to the minersrepresentative. Another proposedchange was to specify the length of timethe submitted plan and the approvedplan would be posted at the mine. Anew paragraph (b) would allow fortimely comments on the submitted planfrom the miners representative.Representatives of miners would receivewritten notice of plan approval. Thefinal rule, for the most part, adopts theproposed rule. However, the final rulerequires that the miners representativebe notified of the submittal of a mineventilation plan and revisions to a plan5 working days prior to submittal andthat the representative of miners beprovided with a copy of the plan uponrequest. It also requires that MSHAprovide a copy of miners’’representative comments to the mineoperator upon request.

Final rule paragraph (a)(3) is dividedinto (a)(3)(i), (a)(3)(ii), and (a)(3)(iii) andcontains new requirements in (a)(1)(i)and (a)(1)(iii). Paragraph (a)(3)(i)requires that the mine operator notifythe representative of miners that a mineventilation plan or a plan revision is tobe submitted to the District Manager forapproval. This notification must begiven at least 5 days prior tosubmission. Paragraph (a)(3)(i) furtherrequires that the operator provide acopy of the plan or revision to therepresentative of miners at the time ofnotification, if requested. Paragraph(a)(3)(ii) requires that the proposed planbe made available for review by therepresentative of miners, and paragraph(a)(3)(iii) requires that the proposedplan or revision be posted on the


bulletin board at the mine and remainposted until it is approved, withdrawn,or denied.

Commenters representing bothoperators and labor suggested that theproposed plan or revision should beprovided to the representative of minersprior to being submitted to the districtmanager for approval. One commentersuggested that the proposed plan orrevision be provided to therepresentative of miners 10 days prior tosubmittal and stated that this couldspeed up the approval process byallowing the miners affected toinvestigate the proposed change and bypermitting the operator and therepresentative of miners the opportunityto reconcile differences prior to theoperator’s seeking approval. Thecommenter pointed out that someexisting wage agreements have adoptedsuch a requirement. The commentersuggested that the rule should alsoinclude such a requirement becauseoperators do not always comply withthe requirements of the agreement. Thiscommenter further suggested that therehave been instances where plans havebeen revised and acted upon before therepresentative of miners was aware thata revision was to be made. Othercommenters suggested that the proposedplan or revision be provided 3 daysprior to submittal. These commentersexpressed different reasons for thesuggestion. One of these commentersstated that the industry has historicallymaintained that since the plan issubmitted to the district manager forapproval, and developed by the mineoperator, the requirement to providecopies to other parties is contrary to theMine Act. However, the commentersfurther stated that their suggestionreflected an attempt to balance allinterests and resolve this matter.

These comments are constructive andMSHA has used all of them to fashiona final rule which is consistent with thestatutory purpose and responsive to themining community. One commenterattempted to relate the rule to terms ofa wage and hour agreement. MSHA doesnot intend or have authority to affectany wage and hour agreement. MSHAbelieves that the involvement of theminers and their representative in theplan approval process will improve thehealth and safety of the Nation’s coalminers. As suggested by commenters,miners who work under the mineventilation plan are often in the bestposition to know the effect of proposedrevisions. MSHA has long recognizedthe importance of input from the minersand their representatives in the plan-approval process. The preamble to theexisting standard discusses the role of

miners and their representatives in thedevelopment of mine ventilation plansin detail. MSHA continues to believethat miners have a stake in theimplementation of the ventilation planat each mine.

The final rule is consistent with theexisting plan approval process and doesnot change the process for developingand approving a mine ventilation plan.The operator continues to be the partyresponsible for developing the mineventilation plan and MSHA continues tobe responsible for reviewing andapproving the plan. The proposed rule,in paragraph (a)(3)(i), would haverequired the operator to provide a copyof a proposed mine ventilation plan orany proposed revision to therepresentative of miners at the time ofsubmittal to MSHA. The final rulerequires the operator to notify therepresentative of miners of the submittalof the proposed plan or revision at least5 working days prior to submittal to thedistrict manager. In addition, a copy isto be provided to the representative ofminers upon request. In most instances,this should provide sufficient time for areview of the proposed plan or revisionand a discussion between the operatorand the representative of miners overconcerns that may exist.

In response to comments, paragraph(a)(3)(i) is further revised in the finalrule to reflect that there are occasionswhen mine ventilation plans must besubmitted and reviewed within a veryshort time frame. In response to aquestion during one of the publichearings on the proposed rule, onecommenter stated that minersunderstand that at times situations mayarise that necessitate an operatorsubmitting a plan or revision to MSHAthat will not allow for the ten (10) dayprovision for the representative of theminers.

Paragraph (a)(3)(i) of the final rulerequires that in the case of a situationrequiring immediate action on a planrevision, notification of the revisionshall be given, and if requested, a copyof the revision shall be provided to therepresentative of miners by the operator,at the time of submittal to the districtmanager. The final rule does not includethe recommendation of one commenterthat the plan or revision be provided tothe representative of miners beforesubmittal because to so require coulddelay approval of a change necessary tohealth and safety. Questions willundoubtedly arise relative to whatconstitutes a situation requiringexpedited action. MSHA does notbelieve that it is possible or appropriateto set forth all circumstances whichwould be covered by the standard.

Should such a situation arise, it wouldbe handled by the district manager ona case by case basis. Generally, thedistrict manager would be guided bywhether the condition, if uncorrected,could result in a health or safety hazardor an imminent stoppage of productionin the mine or an area of the mine.

Paragraph (a)(3)(ii) of the final ruleretains the requirement that a copy ofthe proposed plan or any proposedrevisions be made available forinspection by the representative of theminers. Although some commentersthought this was superfluous in light ofthe requirement in paragraph (a)(3)(i),MSHA believes that this requirementfacilitates the overall approval process.

Paragraph (a)(3)(iii) of the final ruleretains the existing requirement thatcopies of the proposed plan andproposed revisions be posted on themine bulletin board and clarifies thatposting is required at the time ofsubmittal. MSHA believes that theposting requirement is necessary toassure that all miners at a mine willhave the opportunity to review theproposed plan or revision and provideinput during the review process. Onecommenter suggested that proposedplans or proposed revisions be requiredto remain posted for only 30 days fromthe time of submittal so as not to‘‘clutter up the bulletin board.’’ Thissuggestion has not been included in thefinal rule because the mine ventilationplan impacts miners’’ safety and healthand it is important for miners to knowwhich plan provisions are in effectversus those which have not beenapproved. Another commentersuggested that proposed plans andrevisions be posted 10 days prior tosubmittal to MSHA. Thisrecommendation has not been includedin the final rule to assure that there isno confusion between plans that areapproved and proposed provisionsawaiting MSHA approval. To requireposting of proposed plan revisions priorto submission to MSHA would createanother category of mine ventilationplans which could result in unnecessaryconfusion. This is particularly true sincethe representative of miners will havethe plan at least 5 days prior tosubmittal. Because there are occasionswhere a representative of miners doesnot feel it is necessary to review a planor revision, the rule only requires theoperator to provide a copy of the planor revision upon request.

Paragraph (b) of the final rulespecifies procedures that therepresentative of miners may use toprovide input in the mine ventilationplan review process. Under the finalrule, the representative of miners may


submit comments on the proposed planor revisions to the plan to the districtmanager for consideration. Recognizingthat in some instances a decisionrelative to the approval or denial of arevision must be made in a short timeframe, the final rule requires thatcomments be made in a ‘‘timelymanner.’’ MSHA has not defined‘‘timely manner’’ but would consider itto be a period of time that does notunnecessarily delay the approvalprocess. The district manager willcontinue to be available to discuss withthe representative of miners all aspectsof the plan as they affect miners’ healthand safety at any time during orfollowing approval or denial of aproposed plan or revision. Commenterssuggested that the representative ofminers be given a deadline for thesubmission of comments similar to thetime frame established in paragraph(a)(3)(i) for the operator to providecopies of proposed plans and revisionsto the representative of mines. Insupport of this recommendation, thesecommenters stated that unlimited timecould unnecessarily delay the approvalprocess. This recommendation is notincluded in the final rule due to thecomplexity of some plans and revisions.MSHA’s goals are for a process thatincludes both timely review andapproval and opportunity for input fromminers and the Agency believes bothgoals can be accomplished under thefinal rule. MSHA does not believe thatthis provision will unnecessarily delaythe plan approval process since the finalrule, like the proposal, requirescomments to be submitted in a timelymanner.

One commenter suggested thatcomments submitted by therepresentative of miners to the districtmanager as part of the plan approvalprocess should be provided to theoperator. MSHA would expect thatduring the five day period before theplan is submitted to the district managerthe operator and the representative ofminers will discuss the plan and informthe other of their respective positions.MSHA would encourage therepresentative of miners to provide acopy of their comments to the operatorprior to submitting them to MSHA.However, to assure that all parties to theplan approval process are aware of eachothers position paragraph (b) of the ruleprovides that the district manager willprovide the operator with thesecomments upon request.

Paragraph (c)(1) of the final rule isunchanged from the proposal andretains the existing requirement that thedistrict manager notify the operator inwriting of the approval or denial of a

proposed plan or proposed revision.Paragraph (c)(1) adds a requirement thata copy of this notification be sent by thedistrict manager to the representative ofminers. This provision is intended toassure that the representative of minersis kept informed of the status of the planapproval. One commenter pointed outthat quite often, plan provisions aremodified during the review process andthe final approved plan may be differentfrom that which was originallysubmitted. This commenter suggestedthat when a change is made to asubmission, the representative of minersshould be notified of the intendedchange and afforded the opportunity tocomment. MSHA agrees that changes toproposed plans do occur during thereview process. Consistent withMSHA’s philosophy that all parties tothe plan approval process need to beaware of the status of a proposed planor revision, MSHA would expect thatthe operator would inform therepresentative of miners of changes tothe original submittal. However, torequire that notification be provided foreach and every change, no matter howminor, could effectively stop the planreview and approval process. Therefore,the final rule does not adopt thesuggestion of the commenter. Somecommenters interpreted paragraph (c)(1)as requiring the district manager toprovide a copy of the approved plan tothe representative of miners. Paragraph(c)(1) only requires that the districtmanager provide to the representative ofminers a copy of the notification ofapproval or denial that is sent to theoperator.

Proposed paragraphs (f)(1), (f)(2) and(f)(3) are adopted in the final rule.Paragraph (f)(1) is new and requires theoperator to provide the representative ofminers with a copy of the plan orrevision following notification ofapproval, if requested. This facilitatesreview of the plan or revision by therepresentative of miners. Also, the finalrule continues in paragraphs (f)(2) and(f)(3) the existing requirements that theapproved plan or revision be madeavailable for inspection by therepresentative of miners and be postedon the mine bulletin board. Like theproposal, a new requirement inparagraph (f)(3) also requires that anapproved plan or revision must beposted within 1 working day ofnotification of the approval and mustremain posted for the period that theplan is in effect. This helps to assurethat the miners themselves, as well asthe representative of miners, are awareof the provisions of the mine ventilationplan once it is approved.

Commenters both supported andopposed paragraph (f). Those inopposition suggested that some of therequirements were unnecessary in lightof other requirements in the standard.Those supporting the rule suggested thatthe operator should be required toprovide a copy of the approved plan orrevision to the representative of minersand to make it available within 24 hoursof notification of approval. Othercommenters stated that mine ventilationplan approvals are sometimes sent tothe company offices and not necessarilyto the mine. They stated that in thesecases, there could be a delay in copiesof the approved plan or revisionreaching the mine. MSHA crafted thefinal rule in light of the existingparagraph (d) which requires thatoperators instruct persons affected bythe mine ventilation plan or its revisionprior to implementation. Changes to theplan do occur during the approvalprocess; MSHA would expect that theplan or revision would be available tothe person conducting the requiredtraining and, therefore, would beprovided to the representative ofminers.

One commenter suggested that,because the approved plan is required tobe made available for inspection by therepresentative of miners, there is noneed for the plan or revision to beposted on the bulletin board. Thiscommenter identified some logisticalproblems associated with posting ofplans stating that removal of the planfrom the bulletin board could be aproblem.

This same commenter proposed thatnotification of the miners of a revisionto the mine ventilation plan should bethe responsibility of the representativeof miners. MSHA does not agree thatmaking the plan available for inspectionby the representative of miners is anadequate substitute for posting of theplan or revision so as to make itavailable to all miners at all times. Nordoes MSHA agree that the responsibilityfor assuring that miners are aware of therequirements of the plan is the properfunction for the representative ofminers. MSHA recognizes thatdifficulties can exist in assuring that theapproved plan or revision is posted,however the safety benefits of havingthe plan available to the personsaffected by its provisions far outweighany logistical problems.

Section 75.371 Mine Ventilation Plan;Contents

Section 75.371 sets forth theinformation that the operator mustinclude in the mine ventilation plan.Because the plan deals with situations


unique to a mine, the general rulesapplicable in other standards do not fit.For the convenience of the reader, thestandard that sets out the general rule orprovides for an option to include aprovision in a plan will generally crossreference to the appropriate paragraphin § 75.371.

MSHA proposed revisions to existingparagraphs (b), (s), (z) and (bb) of§ 75.371 and reproposed existingparagraph (r). MSHA’s final rule adoptsthe proposal for paragraphs (s), (z) and(bb). MSHA revises its proposedparagraph (r) to make conformingchanges with other provisions. Finally,the final rule retains the existinglanguage for paragraph (b).

As stated in the General Discussionsection of this preamble, provisionsconcerning the installation and removalof mechanized mining equipment thatwere promulgated in May of 1992 aspart of the safety standards forunderground coal mine ventilation werereproposed in May of 1994 as part ofthis rulemaking for the purpose ofreceiving and giving full considerationto all pertinent comments on this issue.Paragraph (r) of the final rule is one ofthe provisions that was reproposed.Section 75.325(d) of the final rulerequires that areas where mechanizedmining equipment, including longwallequipment, is being installed andremoved be ventilated. Paragraph (r) of§ 75.371 requires that the quantity of airthat will be provided be included in themine ventilation plan. Most commenterseither supported the provision, citingthe explosion at the William StationMine, or stated that the standard wasoriginally promulgated inappropriatelyand did not substantively comment onthe requirement. One commentersuggested that the quantity of airspecified in the plan under paragraph (r)should represent the minimum quantitythat will be provided and the locationspecified should be identified as whatwould be typical so as to give the minethe flexibility to adapt to varying mineconditions. This recommendation isconsistent with MSHA’s intent andMSHA has included it in the final ruleto help clarify the rule.

One commenter suggested that theventilation scheme shown in the planshould be representative of the methodof ventilation to be used. MSHA agreesthat the mine ventilation plan shouldinclude a method of ventilation that isrepresentative of that used in the mine.However, MSHA has not adopted thissuggestion since the plan must bespecific enough so that the operator, theminers, the representative of miners,and MSHA are assured that all areas arebeing adequately ventilated.

Paragraph (r) of the final rule requiresthat the mine ventilation plan includethe location where air quantities will beprovided, and the ventilation controlsthat will be used to provide thesequantities. This language was includedin the reproposed provision and in§ 75.325(d), which requires that thequantity of air that will be providedduring the installation and removal ofmechanized mining equipment, thelocation where this quantity will beprovided, and the ventilation controlsthat will be used, be included in themine ventilation plan. In reproposingparagraph (r), MSHA inadvertentlyexcluded from § 75.371(r) therequirement relative to the locationwhere the air quantity is provided. Thefinal rule has been modified in§ 75.371(r) to conform to therequirements of § 75.325(d).

The final rule revises existingparagraph (s) to conform to changes in§ 75.362(d)(1)(iii). The final rule deletesthe portion of existing § 75.362(d)(2)which requires that the mine ventilationplan include the location of tests whichare to be made closer to the workingface than the last permanent roofsupports using extendable probes orother acceptable means. The final rulein paragraph (d)(1)(iii) requires that themine ventilation plan specify thefrequency and location of the methanetests if required more often than 20minutes by § 75.362(d)(1)(iii). Onecommenter suggested adding the words,‘‘or at other locations and frequencies ifapproved by the district manager andcontained in the ventilation plan.’’ Thesuggested clarification is not necessaryand has not been adopted in the finalrule.

The final rule revises paragraph (z) toconform to § 75.364(a). Section75.364(a) addresses the measurementsto be made to evaluate the effectivenessof bleeder systems and the ventilation ofworked-out areas during the weeklyexamination. The final rule requires thatthe locations where these measurementsare made or alternative methods ofproviding these evaluations be includedin the mine ventilation plan. Onecommenter suggested that the locationswhere air measurements are madeshould not be required in the mineventilation plan. The commenter madea similar suggestion relative to therequirement in § 75.364 that airmeasurements be made to evaluate theventilation of worked-out areas anddetermine the effectiveness of bleedersystems. According to the commenter,since no specific air volume is requiredit is not necessary to measure thevolume present. The measurement of airquantity, as well as the other

measurements required by the existingstandard, are essential to evaluate theventilation of worked-out areas anddetermine the effectiveness of bleedersystems. The final rule, therefore, doesnot include the suggested changes ineither § 75.364 or § 75.371(z).

Another commenter suggested thatsince the current standards do notrequire a specific volume of air inbleeder entries, it is unnecessary tomeasure the air volume. Properevaluation of the effectiveness of ableeder system can only be achieved bycomparison of measurements taken inthe bleeder system. In most instances,one of the most importantmeasurements is the air quantity atstrategic points in the bleeder system.Therefore, the final rule includes theproposed requirement that the locationswhere air quantity measurements willbe made in the bleeder system bespecified in the mine ventilation plan.

Existing paragraph (bb) requires thatthe location of ventilating devices usedto control air movement throughworked-out areas be included in themine ventilation plan. The final rulereinstates a requirement contained inthe previous regulation, that thelocation and sequence of construction ofproposed seals also be indicated. Thisrequirement is consistent with§ 75.334(e) which requires that thesequence of construction of seals bespecified in the mine ventilation plan.Some commenters on paragraph (bb)and § 75.334(e) suggested that propersequencing of seals can change due tomining conditions and should not bemade a part of the mine ventilationplan. Another commenter suggested thatbecause the time to get a plan approvedcan be lengthy, it may even createunnecessary hazards. Proper sequencingof seal construction is necessary foreffective ventilation during sealing.Therefore, the final rule requires thelocation and sequence of theconstruction of seals be specified andapproved in the mine ventilation plan.If a delay in seal construction will resultin a hazard to miners, the review andapproval of the plan can be expedited asexplained in the preamble discussion of§ 75.370.

One commenter on paragraph (bb)suggested that the locations ofstoppings, regulators, and bleederconnector entries are better shown onthe mine map with a notation that it issubject to approval under § 75.371. Theexisting standard permits appropriateinformation required under § 75.371 tobe shown on the map required by§ 75.372. This is explained in thepreamble discussion for existing§ 75.371. MSHA recognizes that some of


the information required to besubmitted under § 75.371 is best shownon a map. Rather than require additionalmaps, this information may be shownon the § 75.372 map. When shown onthe § 75.372 map, only that portion ofthe map that contains informationrequired under § 75.371 is subject toapproval by the district manager.

The proposal would have revisedparagraph (b) to reflect the proposedchanges in paragraphs (c) and (d) of§ 75.312 allowing alternative testingmethods for main mine fan automaticclosing doors and fan signals. Becausethe final rule does not include theproposed changes to § 75.312(c) and (d),final rule § 75.371(b) conforms.

Section 75.372 Mine Ventilation MapThe mine ventilation map provides a

basis for understanding how a particularcoal mine is ventilated. An accurate andup to date map of the mine enables theoperator and MSHA to review themine’s ventilation plan to determine theappropriateness of the ventilationsystem to the conditions in the mine.Only through a thorough understandingof the ventilation system can theoperator and others determine whetherthe system is capable of preventingmethane accumulations, possibleexplosions, and high levels of respirabledust. Generally, § 75.372 requires thatthe necessary information be providedon the map.

The final rule revises existingparagraph (b)(3) and adds newparagraphs (b)(19) and (b)(20).Paragraph (b)(3) addresses whichadjacent workings must be shown onthe mine map. The final rule, like theproposal, requires all known adjacentworkings within 1,000 feet of existing orprojected mine workings to be shown onthe mine map, regardless of whether theworkings are located on mine propertyor on adjacent property. The existingrule required that only the adjacentworkings within 1,000 feet be shown ifthey are on mine property.

MSHA has concluded that it isnecessary to require that the mineventilation map include all knownworkings located in the same coalbedwithin 1,000 feet of existing or projectedworkings, regardless of whether theworkings are located on the mineproperty. Hazards, such as methane andwater accumulations and irrespirableatmospheres, exist in old workingswhether located on mine property ornot. MSHA also notes that this revisionmakes paragraph (b)(3) consistent withexisting paragraph (h) of § 75.1200,Mine map. Paragraph (h) of § 75.1200requires that the mine map show alladjacent mine workings within 1,000

feet. Like the previous standard, thisrevision would assure that all adjacentmine workings appear on the § 75.372map in those cases where operators donot use a § 75.1200 map for theirrequired submission.

One commenter suggested that thisrequirement not be included becausemine operators have no legal obligationor authority to force an adjacent landowner to provide the requiredinformation. MSHA recognizes that themine operator may, in some instances,have difficulty obtaining thisinformation. The hazards that existwithin abandoned mines, however,warrant such a requirement.Additionally, as noted previously, thisrequirement is consistent with therequirements of § 75.1200(h) and will,therefore, impose no additional burdenon the operator. Agency experiencereveals that the existing standard,§ 75.1200(h), has not proven to bepractically difficult for compliance. Inaddition, this information would beavailable to the miners and wouldenhance their understanding of theventilation system and aid them in theevent of an emergency.

Another commenter suggested thatthe rule explicitly require that all mineworkings, including workings fromauger mining, highwall mining and stripmining, be shown on the map. Thisrecommendation has not been includedin the final rule because MSHA believesthat the final rule is clear and requiresany workings from other mines, such asstrip, auger and similar workings, to beshown if they are in the same coalbedand are within 1,000 feet of existing orprojected mine workings.

Proposed paragraph (b)(19) is adoptedin the final rule. The proposal wasdrafted in response to commentsreceived at public meetings. It reinstatesthe requirement in the previousstandard that the mine map include theentry height, velocity and direction ofthe air current at or near the midpointof each belt flight where the height andwidth of the entry are representative ofthe belt haulage entry. Paragraph (b)(19)of the final rule should assist theexaminer in rapidly determiningwhether the air is flowing in its normalvelocity and direction duringexamination of the belt entry requiredelsewhere in subpart D. One commentersuggested that this requirement isredundant because the mine ventilationplan already requires that this be‘‘illustrated’’. MSHA does not agree thatthe requirement is redundant sincethere is no such requirement in themine ventilation plan.

MSHA emphasizes that like much ofthe information required to be shown on

the ventilation map, this informationwould not be subject to approval. Whenshown on the § 75.372 map, only thatportion of the map that containsinformation required under § 75.371 issubject to approval by the districtmanager. The information required byparagraph (b)(19) does not fit thiscriteria and therefore is not subject toapproval by the district manager.

As explained in the discussion of§ 75.301, instances have developedwhere operators direct air from anintake air course to ventilate shops,electrical installations, or for otherpurposes, and this air is then coursed tothe surface and is not used to ventilateworking places. Under oneinterpretation of the existing definition,because this air has not ventilated aworking place or a worked-out area, theair course cannot be considered a returnair course. In these instances, the finalrule in § 75.301 expressly permits theredesignation of the affected portion ofthe air course as a return air course.Because it is important that personnel,including examiners, the miners’representative, and representatives ofthe Secretary, know which air courseshave been redesignated, the final rulerequires that these air courses be shownon the map. Paragraph (b)(20) requiresthat the location of redesignated aircourses be shown on the ventilationmap. Commenters were supportive ofthis provision.

Section 75.380 Escapeways;Bituminous and Lignite Mines

When a fire, explosion or otheremergency necessitates an immediateevacuation of a mine, the designatedroute for miners to leave the mine is theescapeway. The escapeway should beappropriately located and designed tobe free of obstructions and hazards toassure safe passage from the hazardousunderground environment. The finalrule addresses requirements forescapeways. Paragraphs (b)(1) and (b)(2)set forth the requirements for thelocation of the escapeway wheninstalling and removing mechanizedmining equipment. Paragraphs (d)(3)through (d)(5) deal with the minimumdimensions of escapeways. Paragraph (f)addresses the equipment that can beused in escapeways and therequirements for fire suppressionsystems on this equipment. Finally,paragraph (i) sets the minimum slope ofan escapeway.

The final rule republishes existingparagraphs (b)(1) and (b)(2) and revisesparagraph (d)(3) through (d)(5), (f) and(i)(2).

Sections 75.380 (b)(1) and (b)(2) of thefinal rule deal with escapeways on


working sections and areas wheremechanized mining equipment is beinginstalled or removed. MSHA adopts theproposal in the final rule. An in-depthdiscussion of the proposal of provisionsconcerning the installation and removalof mechanized mining equipment ispresented in the General Discussionsection of this preamble.

MSHA specifically solicitedcomments on those portions of theproposal dealing with the installationand removal of mechanized miningequipment, including paragraphs (b)(1)and (b)(2) of § 75.380. These paragraphsrequire that an escapeway be providedto areas where mechanized miningequipment is being installed orremoved. Only one substantivecomment was received. The commentersuggested that the location of thebeginning of the escapeway duringequipment installation and removalshould be specified in the mineventilation plan to minimize thepotential for congestion duringmovement of heavy equipment. Thecommenter stated that the proposalwould eliminate all access to a longwallduring the installation or removal of thelongwall equipment except for the facecrosscut, and lead to accidents.

MSHA believes that the locationwhere the loading point will beinstalled and where the loading pointwas last located prior to removal areeasily identifiable and offer the bestchoice. The suggestion of thecommenter has not been adopted in thefinal rule. In addition, the commenternoted that mobile equipment wasneeded during the installation andremoval of longwalls; this equipmentcan be used in the escapeway ifproperly attended and protected withproper fire suppression.

As with the existing rule, paragraph(d)(3) of the final rule generally requiresescapeways to be maintained to a heightof 5 feet from the mine floor to the mineroof, excluding the thickness of any roofsupport. To accommodate mines in lowseams, the rule provides that where thecoalbed is less than 5 feet, theescapeways shall be maintained at leastto the height of the coalbed. As in thepast, convergence, the reduction inentry height due to roof sag or floorheave, which occurs as a naturalgeologic process, will be excluded whendetermining escapeway height unless itwould impede the escape of miners,including disabled persons, in the eventof an emergency. The final rule modifies(d)(3) to provide that in areas of mineswhere escapeways pass through doorsor in areas of mines developed beforeNovember 16, 1992 where escapewayspass across or under overcasts or

undercasts, the height of the escapewaymay be less than 5 feet provided theheight is sufficient to enable miners,including disabled persons, to escapequickly in an emergency. It was broughtto the attention of MSHA by onecommenter that in some instances theremoval of roof support or the loweringof the tops of overcasts may benecessary to provide the 5-foot heightrequired by the existing rule. It has beensuggested that this could result in adiminution of safety.

One commenter suggested thatescapeways should be 6 feet in widthand 5 feet in height without exception.This suggestion has not been adopted inthe final rule. Under the previous rule,escapeway dimensions were addressedthrough criteria and operators routinelyrequested and received approval forlesser dimensions than that in criteriabased on a performance test referred toas a ‘‘stretcher test.’’ As applied, thistest required 4 persons to carry a fifthperson on a stretcher through the areain question. The purpose of the‘‘stretcher test’’ was to demonstrate thatthe lesser dimension would not delayescape. The final rule permits lesserescapeway heights and widths underspecific circumstances provided theheight and width maintained enableminers to escape quickly in anemergency. The final rule requires thatwhen there is a need to determinewhether sufficient height or width isprovided, MSHA may require a stretchertest where 4 persons carry a minerthrough the area in question on astretcher.

This commenter suggested that theresults of a stretcher test could bemanipulated by having the most fitminers carry the smallest miner. MSHAcontinues to believe that the stretchertest is appropriate. MSHA’s experienceis that the stretcher test provides a goodmeasure of the ability of miners toescape.

Since the escape of miners is notimpeded, the demonstration that thereis no delay in escape assures that thereis no reduction in safety.

MSHA received similar commentsregarding the dimensions of escapewaysdeveloped on or after November 16,1992, (the effective date of the existingrule). Commenters suggested that wherethese escapeways pass across or underovercasts or undercasts, the height ofthe escapeway should be permitted tobe less than 5 feet provided the heightis sufficient to enable miners, includingdisabled persons, to escape quickly inan emergency situation. This suggestionis not adopted in the final rule sincesufficient clearance should have beenprovided in these escapeways through

proper planning and engineering. Also,MSHA’s experience does not reveal anycompliance problems associated withthe standards since November 1992.

One commenter recommendedchanging the phrase ‘‘disabled persons’’in paragraph (d)(3) to ‘‘injured persons.’’In support of this recommendation, thecommenter stated that the phrase isintended to include persons who maybe injured but not necessarily disabled.MSHA does not believe that the changeis needed since there are manysituations that occur underground thatcan result in a person being injured butnot severely enough to need assistance(i.e. disabled) to be transported from themine. An escapeway that will permitthe transport of disabled persons, i.e.the more severely injured persons, canbe expected to accommodate personswith lesser injuries. The term disabledwith respect to the concept of injuredhas existed in the regulations for over 25years and MSHA is not aware of anyproblems with its use.

Questions arose during informationalmeetings regarding the requirements forthe height of doors in escapeways. Thefinal rule, like the proposal, permitsdoor heights of less than 5 feet undercertain conditions. Under the previousrule, escapeway dimensions, includingdoor heights, were addressed throughcriteria and operators routinelyrequested and received approval forlesser dimensions than that in criteriabased on a performance test referred toas a ‘‘stretcher test.’’ Under the finalrule, door heights of less than 5 feet arepermitted provided the operator candemonstrate that persons, includingdisabled persons, can escape withoutdelay. The method of demonstrationwould be the stretcher test, the same asfor the escapeway. Additionally, thereare normally few doors in an escapewayand the distance traversed in a door isvery short. Passing the stretcher testassures that there would be nodiminution of safety under the newprovision. Also, since significantpressure differentials can exist inescapeways, doors which are less than5 feet are easier to open.

Paragraph (d)(4) of the existing rulerequires the escapeways be maintainedat least 6 foot wide with someexceptions. Widths of less than 6 feetare permitted in either the primary orthe alternate escapeway in instanceswhere supplemental roof support isnecessary and where the route of travelpasses through doors or otherpermanent ventilation controls. In bothcases, existing paragraph (d)(4) requiresthat the escapeway be at least 4 feetwide. Under the final rule, paragraph(d)(4)(iii) permits the alternate


escapeway to be less than 4 feet wideunder certain conditions.

Paragraph (d)(4)(iii) applies to thealternate escapeway only and allows theescapeway width to be less than 4 feetfor the same conditions addressed inparagraphs (i) and (ii) if it can bedemonstrated that sufficient width ismaintained to enable persons, includingdisabled persons, to escape quickly inan emergency. The conditions thatcould warrant lesser widths are thelocations where the alternate escapewaypasses through doors or otherpermanent ventilation controls,including constructed approaches topermanent ventilation controls andfacilities addressed in paragraph (d)(6),or where supplemental roof support isrequired.

One commenter stated that thealternate escapeway should bemaintained at a minimum width of 4feet without exception and noted thaton several occasions miners have beenforced to use the alternate escapeway inemergencies. The commenter noted thatit could be difficult to transport aninjured person on a stretcher at widthsunder 4 feet. The final rule requires thatwhen there is a need to determinewhether adequate width is provided, thestretcher test would be applied.

Under the previous rule, approval hadbeen granted for reduced escapewaywidths based on the stretcher test. Theseapprovals were due to the need toprovide additional roof support and, insome cases, the need for passagethrough ventilation controls.Additionally, as newer portions of amine age and require additional roofsupport, the final rule allows widths ofless than 4 feet in the alternateescapeway where this roof supportexists, provided the stretcher test ispassed. MSHA believes this approachachieves the intended result of thestandard while at the same timeaddressing the safety issues of providingnecessary supplemental roof supportand permitting travel in the alternateescapeway.

The preamble to the proposal statedthat under the existing standard§ 75.380(d)(4) mobile equipment shouldnot be considered when determiningescapeway width unless the equipmenthas been permanently abandoned in theescapeway or would be obstructing theescapeway for a significant portion of ashift. Commenters objected that thisinterpretation would be undulyrestrictive and impractical. Commentersnoted that certain parked mobileequipment would enhance miner safetywhere the equipment could be used totransport people out of the mine in theevent of an emergency.

Experience under the existing and theprevious rule indicates that track-mounted and rubber-tired equipmentwhich could be used for evacuationshould be excluded when determiningescapeway widths. Track-mountedsupply cars enhance safety by providinga readily available supply of rock dust,roof support material, and otheressential safety related material. Section75.214 requires that a supply ofsupplementary roof support materialand the tools and equipment necessaryto install the materials be available at areadily accessible location on eachworking section or within 4 crosscuts ofeach working section. In contrast, theAgency received comments thatescapeways should be maintained atleast 6 feet in width except in rare caseswhere roof supports could reduce thewidth to no less than 4 feet over alimited distance.

The final rule takes a practicalapproach, preserving the requirementthat escapeways must be of sufficientwidth to enable miners, includingdisabled persons, to escape quickly inan emergency. The final rule alsorecognizes that certain necessary miningand transportation equipment is locatedon and near working sections. Forexample, necessary supply carscontaining safety related material likerock dust, roof support, ventilationcontrol construction material, etc., isallowable. Additionally, longwallsection equipment commonly includes,but may not be limited to, starter box,water pump, section belt tailpiece andtakeup assembly, section transformer,and emulsion pump. Because thisequipment is necessary to the operationof the longwall, it also is permitted tobe in the escapeway near the workingsection under the final rule. Incontinuous miner sections as well aslongwall sections, mantrips andpersonnel transportation equipment,which could be utilized in anemergency evacuation, is allowable. Thefinal rule would not prohibit thisequipment in escapeway entries on ornear working sections. The rule wouldrequire, however, that sufficientclearance be maintained to permit rapidescape.

This aspect of the final rule maintainsthe historical approach taken toaddressing issues of clearance in theconfined environment of undergroundcoal mines. The final rule, whilepermitting reduced dimensions nearworking sections as discussed above,requires that the escapeways always bemaintained of sufficient width to enableminers, including disabled persons, toescape quickly in an emergency. Asdiscussed elsewhere in this preamble,

the Agency will assess the adequacy ofescapeway widths in such areas bymeans of the stretcher test to assure thatthe width is sufficient to enable miners,including disabled persons, to escapequickly in an emergency.

Like the proposal, the final rule inparagraph (d)(5) revises the existinglanguage dealing with the location ofescapeways. It provides that escapewaysshall be located to follow the mostdirect, safe and practical route to thenearest mine opening suitable for thesafe evacuation of miners. A questionarose during an informational meetingas to whether MSHA intended that theexisting rule eliminate the requirementthat escapeways be routed to the‘‘nearest mine opening.’’ It was notMSHA’s intent to change thisrequirement from the previous standard.The existing requirement that theescapeway follow the most direct routeto the surface would, in fact, require theroute to go to the nearest mine opening.However, to eliminate any confusionthat may exist, the final rule revisesparagraph (d)(5) and adopts languagesimilar to that in previous regulation,§ 75.1704–2(a), that is, that theescapeway must follow the most direct,safe and practical route to the nearestmine opening suitable for the safeevacuation of miners.

One commenter stated thatescapeways should not be permitted topass an opening to be routed to a moredistant opening. Another commenterstated that the nearest mine openingmay not always be the safest due to roofconditions or other factors. MSHAacknowledges that the nearest mineopening may not always be the safestroute to the surface. A number of factorsaffect whether or not the safest, mostdirect, practical route has been selected.These factors include roof conditions,travel height, fan location, physicaldimensions of the mine opening, andsimilar considerations. For example, ifbad roof conditions are present alongthe shortest direct route and those roofconditions are beyond reasonablecontrol, then an alternate ‘‘safe’’ routedesignated by the mine operator may beappropriate. However, the presence ofroof falls does not necessarily indicatethat the passageway would not besuitable for evacuation if it is reasonableto rehabilitate the area. By way ofanother example, where coal seamthickness varies to the extreme, theshortest route may be through lowercoal, making travel relatively slow anddifficult. An alternate route through ahigh passageway may permit easiertravel. Such an alternate route, althoughlonger, may be more practical andtherefore may be more appropriate.


Similarly, there can be other instanceswhere the ‘‘nearest mine opening’’ maynot be suitable for safe evacuation ofminers. For example, an old mine shaftmay not be safe for travel because ofbadly deteriorated conditions, such as adeteriorated shaft lining or deterioratedtimbers, even though the shaft is stillsuitable for mine ventilation purposes.

As with the existing standard, minedevelopment projections do not have tobe altered to provide additional rooms,entries, or crosscuts for the sole purposeof providing a passageway to the nearestmine opening. However, theconstruction of ventilation controls suchas stoppings, overcasts and undercasts,or the installation of an escape facilitymay be required to provide the mostdirect, safe and practical route to thesurface.

One commenter suggested that MSHAshould require an escapeway plan to beapproved by the MSHA district managerto assure the most direct route to thesurface. Existing standards require thatescapeways be shown on the ventilationmap. In addition, as with otherregulations, inspectors assess whetherescapeways follow the most direct, safeand practical route to the surface duringeach regular inspection. Accordingly,MSHA does not believe that anadditional plan is necessary.

Existing paragraph (f) establishes therequirements for ventilation of theprimary escapeway and identifies whichequipment can be operated in theprimary escapeway and the firesuppression requirements for thisequipment. The final rule, like theproposal, modifies paragraph (f) toexplicitly identify the equipment that isnot permitted in the primary escapewayand to specify the types of firesuppression systems that are to be usedand the conditions under which each isto be used on equipment permitted inthe primary escapeway. This is done byreplacing existing paragraphs (f)(1) and(f)(2) with paragraphs (f)(1) through(f)(7) in the final.

Existing paragraph (f)(1) requires thatone escapeway that is ventilated withintake air be designated as the primaryescapeway and prohibits certainequipment from being used in theprimary escapeway in areas developedafter November 15, 1992. Further,paragraph (f)(1) requires firesuppression systems on mobileequipment that is operated in theprimary escapeway. The final ruletransfers the part of existing paragraph(f)(1) that specifies the area of theprimary escapeway affected toparagraph (f)(2).

The existing rule limited theinstallation or use of certain equipment

in areas of the primary escapewaydeveloped after November 15, 1992.Paragraph (f)(2) of the final rulemodifies the existing rule for clarity andexpands the application of certainrequirements contained in paragraphs(f)(3) through (f)(7) to the entire primaryescapeway except those areas of theprimary escapeway developed prior toMarch 30, 1970 where separation of theprimary escapeway from the belt andtrolley haulage entries did not exist asof November 16, 1992. For areas ofmines developed after September 15,1992, (those areas covered by theexisting rule) the provisions ofparagraphs (f)(3) through (f)(7) will beeffective as of March 11, 1997. For otherareas covered by the rule, MSHA hasprovided for a 1 year phase in period toallow mine operators time to effectivelyplan and implement the necessarychanges. The phase in period applies toareas of a primary escapeway developedbetween March 30, 1970 and November16, 1992, and to areas of the primaryescapeway developed prior to March 30,1970 where separation of the belt andtrolley haulage entries from the primaryescapeway existed prior to November16, 1992.

Paragraph (f)(3) prohibits certainequipment from being in the primaryescapeway. Paragraphs (f)(4) and (f)(5)deal with fire protection for mobileequipment that is permitted in theprimary escapeway and paragraph (f)(6)addresses a specific circumstance whenmobile equipment may operate in aprimary escapeway without a firesuppression system. Paragraph (f)(7), aprovision added to the proposedlanguage in response to comments,allows the use of designated emergencyvehicles or ambulances in the primaryescapeway.

One commenter suggested that thefinal rule should not provide anexception for all areas where separationof the primary escapeway from the beltand trolley haulage entry does not exist.The commenter recognized, however,that Congress granted an exemptionfrom separation requirements for areasof the primary escapeway developedprior to March 30, 1970, the effectivedate of the Act. The intent of theproposal was to provide an exemptionfrom the requirements of proposedparagraphs (f)(3) through (f)(6) for thesesame areas. The commenter points outthat the proposal would have extendedthe exemption to other areas of theprimary escapeway where, for onereason or another, separation did notexist on November 16, 1992, theeffective date of the existing rule. Thefinal rule modifies the proposal toclarify that the exemption only applies

to those areas of the escapeway thatwere developed prior to March 30, 1970and where separation did not exist onNovember 16, 1992.

Another commenter correctlyinterpreted proposed paragraph (f)(2) asextending the requirement that limitsthe types of equipment permitted inprimary escapeways to areas of the minedeveloped prior to November 16, 1992.The commenter stated that the proposedregulation would pose great cost to theindustry with no appreciable safetybenefit derived. A review of the firehistory relative to both stationary andmobile equipment indicates that firescan and do occur on this equipment.Mobile equipment by design is intendedto provide flexibility in movement andis capable of operating anywhere in themine. Although the accident reports donot specify whether the mobileequipment that caught fire was in theprimary escapeway when the firestarted, it is reasonable to conclude thatat least some of these fires did occur inthe primary escapeway. MSHAcontinues to believe that given theimportance of the primary escapeway tothe safety of miners, the extension of therequirements for operation of equipmentin the primary escapeway is necessaryand appropriate.

Paragraph (f)(3) lists the equipmentthat is not permitted in the primaryescapeway. Under paragraph (f)(3)(i) ofthe final rule, operating dieselequipment without an automatic firesuppression system is prohibited in theprimary escapeway unless it is attended,except as provided in paragraphs (f)(6)and (f)(7). One commenter stated thatattended diesel equipment with amanual fire suppression system presentsno fire hazard. Another commentersuggested that unattended dieselequipment should be prohibited. Whendiesel equipment is operated in theprimary escapeway and is properlyattended and equipped with a manualfire suppression system, the equipmentoperator can immediately respond to afire, and the safety afforded by theexisting standard is maintained. If themachine is shut off, however,attendance is not necessary. Whendiesel equipment is to be operatedunattended, an automatic system isrequired to protect against fire.

One commenter stated that‘‘attended’’ should be interpreted tomean that the operator is on or withinsight of the vehicle. Another commenterurged that the standard be clarified torequire that the operator be at thecontrols of the equipment. For thepurposes of § 75.380(f), by ‘‘attended’’MSHA means that the equipmentoperator would be on the mobile


equipment or immediately adjacent tothe equipment and be capable ofactivating the fire suppression system inthe event of a fire.

The existing standard permitsequipment to be in the escapeway forpurposes of transporting miners andmaterials and for maintaining theescapeway but does not expresslyprohibit the haulage of coal in theprimary escapeway. As a matter ofclarification, the final rule specificallyprohibits coal haulage in the primaryescapeway unless incidental to cleanupand maintenance of the escapeway. Onecommenter supported the proposedprohibition of coal haulage noting thatcoal haulage would provide a readysource of fuel to a machinery-initiatedfire. Several commenters expressed aconcern that incidental coal haulageassociated with cleanup andmaintenance of the primary escapewaywould be prohibited under the proposedstandard. Cleanup and maintenance ofthe primary escapeway must bepermitted. Therefore, the final rulemodifies the proposal to permit mobileequipment to haul coal if incidental tocleanup and maintenance of the primaryescapeway.

Paragraph (f)(3)(iii) prohibitscompressors in the primary escapewayexcept as provided in subparagraphs(f)(3)(iii) (A) through (C). Subparagraph(A) allows compressors necessary tomaintain the escapeway in safe,travelable condition; (B) allowscompressors that are components ofequipment such as locomotives androck dusting machines; and, (C) allowscompressors of less than fivehorsepower due to the limited firehazard associated with their operation.

One commenter described an incidentinvolving a compressor in an intakeairway, which was located in a fireproofenclosure but was improperlyventilated. According to the commenter,smoke and contaminants spreadthroughout the intake entry and reachedthe section, which was then evacuated.This illustrates the importance ofproviding adequate protection from thepossible spread of smoke andcontaminants associated withcompressor fires or overheating.

Paragraph (f)(3)(iv) of the final ruleadds battery chargers to the equipmentincluded in the proposal that ispermitted in the primary escapewayprovided they are located on or near aworking section and moved as thesection advances or retreats. In all otherrespects, paragraph (f)(3)(iv) of the finalrule adopts the proposal. Underparagraph (f)(3)(iv), undergroundtransformer stations, battery chargingstations, substations, and rectifiers

cannot be located in the primaryescapeway except: (A) where necessaryto maintain the escapeway in safe,travelable condition; and (B) batterychargers and rectifiers and powercenters with transformers that are eitherdry-type or contain nonflammableliquid, provided they are located on ornear a working section and are movedas the section advances or retreats. Thefirst exception allows work to beperformed in the primary escapeway toassure its integrity. The second providesfor the locations of the describedequipment at or near working sectionsif the equipment moves with thesection. Equipment at or near workingsections will normally be within a fewcrosscuts of the working face. In manycases, particularly with battery chargers,there may be no practical alternative tolocating this equipment in theescapeway. In addition, § 75.340provides additional protection whenusing underground electricalequipment.

Paragraph (f)(3)(v) of the final ruleadopts the proposal and prohibits waterpumps from being in the primaryescapeway except as provided underparagraphs (f)(3)(v)(A) through(f)(3)(v)(F). The pumps that arepermitted in the primary escapeway arethe same ones that are excepted fromthe requirements of § 75.340 due to thelow potential for fire associated withtheir operation. They include: waterpumps necessary to maintain theescapeway in safe, travelable condition;submersible pumps; permissible pumpsand associated permissible switchgear;pumps located on or near a workingsection that are moved as the sectionadvances or retreats; pumps installed inanthracite mines; and small portablepumps. While the existing rule refers tothe electrical equipment described in§ 75.340 (a) and (b)(1), the final rule,like the proposal, lists the affectedequipment for the convenience of thereader. Like § 75.340, paragraph (f)(3)(v)applies to water pumps and emulsionpumps when they are located on or nearthe working section and are moved asthe section advances or retreats. Onecommenter agreed that pumps may benecessary to maintain and rehabilitatethe primary escapeway but suggestedthat a time limit be placed on the lengthof time the pump is allowed to remainin the escapeway. MSHA believes thatspecific conditions at the mine willgovern the amount of time required forany necessary pumping. Therefore,MSHA has not included the suggestionin the final rule since the decisionrelative to time must be made on a case-by-case basis, as appropriate.

Paragraph (f)(4) of the final ruleadopts MSHA’s proposal with onechange. As proposed, paragraph (f)(4)would have required the use of firesuppression systems on mobileequipment operated in the primaryescapeway, and would have allowedexceptions for continuous miners and asprovided in § 75.380 (f)(5) and (f)(6).The final rule adds an additionalexception for emergency vehicles orambulances as provided in§ 75.380(f)(7). Unlike the existingstandard, the final rule in paragraph(f)(4) permits certain mobile equipmentoperated in the primary escapeway to beprotected with a manual firesuppression system instead of anautomatic system, provided it isattended by a person trained in the useand operation of the fire suppressionsystem. MSHA believes that when apiece of equipment is operated in theprimary escapeway and is properlyattended and equipped with a manualfire suppression system, the equipmentoperator can immediately respond to thesituation, and the safety afforded by theexisting standard is maintained.

One commenter stated that noelectrical, battery or diesel equipment,or other equipment such as compressorsshould be allowed in the primaryescapeway, except for the purpose ofmaintenance of the escapeway, and thatthis equipment should have anappropriate fire suppression system.Because travel in the escapeway incertain mining systems is essential forsafety given the design of the miningsystem used, the recommendation of thecommenter has not been adopted in thefinal rule. Instead, the final ruleprovides that certain types of miningequipment can be operated in theprimary escapeway provided the safetyprecautions set out in the standard arefollowed. One commenter stated thatthe rule should only apply to mobileequipment which is operated in theprimary escapeway, since equipmentnot operating presents little or nohazard. MSHA agrees and hasincorporated this clarification into thefinal rule.

Commenters indicated that it issometimes necessary to withdraw faceequipment, such as continuous miners,roof bolting machines and shuttle cars,into the primary escapeway for a shortdistance beyond the loading point. Theequipment is sometimes parked and leftthere on down shifts or between shifts.MSHA notes that, as clarified, the finalrule does not prohibit this practice.Because the equipment would beattended when operated and is providedwith manual fire suppression, the


equipment may be operated in theprimary escapeway.

Following promulgation of theexisting rule, some persons construedthe requirement for an automatic firesuppression system to apply to electricface equipment. As explained in thepreamble to the proposal, this was notthe intent of MSHA. To clarify its intent,MSHA issued Program Policy Letter No.P92–V–4 on November 16, 1992,addressing the operation and location ofequipment in primary escapeways.Under existing regulations in SubpartL—Fire Protection, face equipment isrequired to be protected by a manualfire suppression system. The final rulerecognizes and generally conforms withthis requirement. Other than for anexception to permit a situation such asthe movement of continuous miningmachines between sections without acontinuous water supply, the final rulerequires that when face machinery,equipped with a manual firesuppression system, is operated in theprimary escapeway, it must be attendedby a person trained in the properfunction and use of the fire suppressionsystem. The continuous miningmachine exception recognizes that thefire suppression system for thecontinuous mining machine often relieson a water supply that may beimpracticable to provide duringequipment moves.

The final rule requires in paragraph(f)(4) that with exceptions forcontinuous mining machines and asprovided in paragraphs (f)(5), (f)(6), and(f)(7), each piece of mobile equipmentoperated in primary escapeways shall:(1) be equipped with manually operatedfire suppression systems installed incompliance with §§ 75.1107–3 through75.1107–16 and be attendedcontinuously; or (2) be equipped withan automatic fire suppression systemthat is capable of both automatic andmanual activation and installed incompliance with §§ 75.1107–3 through75.1107–16. Fire suppression systemswhich were installed to meet the 1992rule will continue to be accepted.

Under paragraph (f)(5) of the finalrule, personnel carriers and smallpersonnel conveyances designed andused solely for the transportation ofpersonnel and small hand tools can beoperated in the primary escapeway ifeither of the requirements underparagraphs (i) or (ii) are met. This classof equipment would not include diesel-powered pickup trucks, for example,which would be governed by paragraph(f)(4). Paragraph (i) requires amultipurpose dry chemical typeautomatic fire suppression systemcapable of both manual and automatic

activation. Paragraph (ii) provides analternative for a class of small, batterypowered, golf cart type, equipment usedfor transport of persons and small handtools. In this case, fire extinguishersmay be used in lieu of a fire suppressionsystem.

Commenters questioned the need forautomatic systems on the class ofequipment consisting of small, batterypowered, golf cart type equipment. Onecommenter suggested that a manual firesuppression system should be accepted.After a review of the issue, MSHA hasconcluded that some types of mobileequipment present a very limited firehazard. In the case of small, batteryoperated, golf cart type, conveyancesdesigned and used for the transport ofpersonnel and small hand tools,considering the limited hazard, atrained operator provided with two 10pound multi-purpose dry chemical fireextinguishers is equivalent in protectionto a fire suppression system.Accordingly, as an alternative underparagraph (ii), small battery powered,golf cart type, equipment may beoperated in the primary escapeway ifprovided with two 10 pound multi-purpose dry chemical fire extinguishers.Unlike diesel powered equipment, thegolf cart type of equipment is shut offwhen not operating and, therefore,attendance is not an issue. The 10pound units are standard sizeextinguishers and are appropriate forthe equipment involved.

The system used in accordance withparagraph (i) must be suitable for theintended application and listed orapproved by a nationally recognizedindependent testing laboratory. Thelanguage was proposed as twoparagraphs but has been combined inthe final rule under paragraph (i) and analternative has been added as paragraph(ii). The types of machinery which fallunder paragraph (f)(5) are not requiredto meet the additional requirements of§§ 75.1107–3 through 75.1107–16. Forexample, it would be impractical andwould not enhance safety to apply theminimum dry chemical poundagerequirements of § 75.1107–9 to smallequipment designed and used solely forpersonnel and small hand tools.

During informational meetings, it wassuggested that the term ‘‘dry chemical’’would be more accurate and appropriatethan the term ‘‘dry powder’’ used in theexisting standard. Like the proposal, thefinal rule adopts this language. MSHAreceived no comments on this proposedrevision

Paragraph (f)(6) of the final ruleprovides an exception to the generalrequirement and allows mobileequipment not provided with a fire

suppression system to operate in theprimary escapeway if no persons areinby other than persons directlyengaged in the use or moving of theequipment. This provision of the finalrule allows for the necessary movementof face equipment, such as betweensections.

One commenter stated that theexemption provided in (f)(6) should beexpanded to allow equipment that doesnot have a fire suppression system to berelocated provided monitoringequipment is utilized for carbonmonoxide or smoke and two-waycommunication is available to notifyappropriate persons. The final rule doesnot adopt this suggestion. Duringmoves, equipment is often laboring atmaximum capacity and there can beseveral machines operatingsimultaneously. Under these conditions,equipment fires can develop quicklyand the products of combustion wouldbe carried to inby workers by theventilating current. By permitting onlyworkers who are directly engaged in theoperation or movement of theequipment, the final rule prevents otherworkers from being exposed to thehazards of a fire on the equipment beingmoved. Workers operating or engaged inmoving the equipment will be in aposition to quickly identify the hazardand take necessary action.

Another commenter objected to theprovision stating that fire suppressionshould be required on all equipment inthe primary escapeway. This suggestionhas not been adopted in the final rule.MSHA does not agree that firesuppression is needed when no personsare inby or downstream of theequipment being moved. MSHA hasconcluded that either these machinesshould be equipped with firesuppression, or fire extinguishers as in(f)(5)(ii), or no persons should be inbythe location where the equipment isbeing operated except those personsdirectly engaged in the operation ormovement of the equipment.

Another commenter suggested thatthe wording of (f)(6) could be read toallow miners to work on a longwall facewhile equipment not equipped with firesuppression is operated anywhere in theprimary escapeway. This is notpermitted by the standard. By includingthe phrase, ‘‘. . . except those personsdirectly engaged in using or moving theequipment’’, the persons affected areonly those persons in the immediatevicinity of the machine. With nopersons working inby, the use ofmachinery without a fire suppressionsystem would not expose persons to thehazard of toxic gases and fumes from afire on the equipment. The language


also would not permit persons tooperate mobile equipment without a firesuppression system in the primaryescapeway while miners aredownstream working on a longwall face.The controlling factor is whether thepersons inby are directly engaged inusing or moving that particular piece ofequipment. If they are, and no one elseis inby, the equipment may be operatedwithout a fire suppression system. Forexample, when moving a longwallshield, no one would be permitted to beinby the machine being used to movethe shield if the machine is notprovided with a fire suppression systemexcept those persons moving the shield.This would include miners operatingother pieces of equipment to move othershields.

Paragraph (f)(7) modifies the existingrule to include a new exemption to therequirement that mobile equipmentoperated in primary escapeways have afire suppression system. Paragraph (f)(7)permits mobile equipment designatedand used only as emergency vehicles orambulances to operate in the primaryescapeway without fire suppressionsystems. It was suggested to MSHA thatcertain types of emergency equipment,such as diesel powered ambulances,should be exempt from the requirementsfor fire suppression systems. Commentswere received suggesting thatambulances should be exempt becausespace is extremely limited on thesevehicles and because they are usedinfrequently. MSHA recognizes thepotential benefit in the use of this typeof equipment. Another commenterobjected, foreseeing potential abuses ofthe exemption by mine operators whowould designate equipment asambulances but use it as ordinaryequipment. The final rule permitsemergency vehicles to be operated inthe primary escapeway without firesuppression systems only when thisequipment is used for medicalemergencies.

This existing rule requires inparagraph (i)(2) that mechanical escapefacilities be provided and maintainedfor, ‘‘. . . each slope that is part of adesignated escapeway that is eitherinclined 18 degrees or more from thehorizontal or is inclined 9 degrees ormore from the horizontal and is greaterthan 1,000 feet in length.’’ Duringinformational meetings, MSHA becameaware of a concern that existingparagraph (i)(2) would permit slopes ofsignificant length and inclination toexist without any mechanical escapefacilities. An example would be a slopeof 900 feet inclined less than 18 degreesfrom the horizontal. It was suggestedthat such a slope could be particularly

difficult for passage of injured personsunder cold and icy conditions ifmechanical escape facilities were notprovided. In light of this concern,MSHA proposed to require thatmechanical escape facilities be providedand maintained from the coal seam tothe surface for each slope that is part ofa designated escapeway and is inclinedmore than 9 degrees from the horizontal.The final rule adopts the proposal.

One commenter objected to proposedparagraph (i)(2) indicating that facilitiesare unnecessary in low angle slopeswhich are of short length. Othercommenters believed that the 1992standard was appropriate. Anothercommenter indicated support for theproposal as a way to enable persons toescape quickly in an emergency. Thiscommenter also noted that escape canbe very difficult in icy winter conditionsin some slopes. After consideration ofthe comments received, MSHAconcludes that the proposal wasappropriate and the final rule adoptsthis aspect of the proposal.

One commenter suggested thatproposed paragraph (i)(2) could beinterpreted as requiring mechanicalescape facilities for slopes that occurnaturally underground. It was notMSHA’s intent to apply paragraph (i)(2)to slopes other than from the coal seamto the surface. The final rule clarifiesthis and requires that mechanical escapefacilities be provided for each slopefrom the coal seam to the surface that ispart of a designated escapeway and isinclined more than 9 degrees from thehorizontal.

Like the proposal, the final rule inparagraph(d)(5) revises the existinglanguage dealing with the location ofescapeways. It provides that escapesshall be located to follow the mostdirect, safe and practical route to thenearest mine opening suitable for thesafe evacuation of miners. A questionarose during an informational meetingas to whether MSHA intended that theexisting rule eliminate the requirementthat escapeways be routed to the‘‘nearest mine opening.’’ It was notMSHA’s intent to change thisrequirement from the previous standard.The existing requirement that theescapeway follow the most direct routeto the surface would, in fact, require theroute to go to the nearest mine opening.However, to eliminate any confusionthat may exist, the final rule revisesparagraph (d)(5) and adopts languagesimilar to that in previous regulation,§ 75.1704–2(a), that is, that theescapeway must follow the most direct,safe and practical route to the nearestmine opening suitable for the safeevacuation of miners.

One commenter stated thatescapeways should not be permitted topass an opening to be routed to a moredistant opening. Another commenterstated that the nearest mine openingmay not always be the safest due to roofconditions or other factors. MSHAacknowledges that the nearest mineopening may not always be the safestroute to the surface. A number of factorsaffect whether or not the safest, mostdirect, practical route has been selected.These factors include roof conditions,travel height, fan location, physicaldimensions of the mine opening, andsimilar considerations. For example, ifbad roof conditions are present alongthe shortest direct route and those roofconditions are beyond reasonablecontrol, then an alternate ‘‘safe’’ routedesignated by the mine operator may beappropriate. However, the presence ofroof falls does not necessarily indicatethat the passageway would not besuitable for evacuation if it is reasonableto rehabilitate the area. By way ofanother example, where coal seamthickness varies to the extreme, theshortest route may be through lowercoal, making travel relatively slow anddifficult. An alternate route through ahigh passageway may permit easiertravel. Such an alternate route, althoughlonger, may be more practical andtherefore may be more appropriate.Similarly, there can be instances wherethe ‘‘nearest mine opening’’ may not besuitable for safe evacuation of miners.For example, an old mine shaft may notbe safe for travel because of badlydeteriorated conditions, such as adeteriorated shaft lining or deterioratedtimbers, even though the shaft is stillsuitable for mine ventilation purposes.

As with the existing standard, minedevelopment projections do not have tobe altered to provide additional rooms,entries, or crosscuts for the sole purposeof providing a passageway to the nearestmine opening. However, theconstruction of ventilation controls suchas stoppings, overcasts and undercasts,or the installation of an escape facilitymay be required to provide the mostdirect, safe and practical route to thesurface.

One commenter suggested that MSHAshould require an escapeway plan to beapproved by the MSHA district managerto assure the most direct route to thesurface. Existing standards require thatescapeways be shown on the ventilationmap. In addition, as with otherregulations, inspectors assess whetherescapeways follow the most direct, safeand practical route to the surface duringeach regular inspection. Accordingly,MSHA does not believe that anadditional plan is necessary.


Existing paragraph (f) establishes therequirements for ventilation of theprimary escapeway and identifies whichequipment can be operated in theprimary escapeway and the firesuppression requirements for thisequipment. The final rule, like theproposal, modifies paragraph (f) toexplicitly identify the equipment that isnot permitted in the primary escapewayand to specify the types of firesuppression systems that are to be usedand the conditions under which each isto be used on equipment permitted inthe primary escapeway. This is done byreplacing existing paragraphs (f)(1) and(f)(2) with paragraphs (f)(1) through(f)(7) in the final.

Existing paragraph (f)(1) requires thatone escapeway that is ventilated withintake air be designated as the primaryescapeway and prohibits certainequipment from being used in theprimary escapeway in areas developedafter November 15, 1992. Further,paragraph (f)(1) requires firesuppression systems on mobileequipment that is operated in theprimary escapeway. The final ruletransfers the part of existing paragraph(f)(1) that specifies the area of theprimary escapeway affected toparagraph (f)(2).

The existing rule limited theinstallation or use of certain equipmentin areas of the primary escapewaydeveloped after November 15, 1992.Paragraph (f)(2) of the final rulemodifies the existing rule for clarity andexpands the application of certainrequirements contained in paragraphs(f)(3) through (f)(7) to the entire primaryescapeway except those areas of theprimary escapeway developed prior toMarch 30, 1970 where separation of theprimary escapeway from the belt andtrolley haulage entries did not exist asof November 16, 1992. For areas ofmines developed after September 15,1992, (those areas covered by theexisting rule) the provisions ofparagraphs (f)(3) through (f)(7) will beeffective as of March 11, 1997. For otherareas covered by the rule, MSHA hasprovided for a 1 year phase in period toallow mine operators time to effectivelyplan and implement the necessarychanges. The phase in period applies toareas of a primary escapeway developedbetween March 30, 1970 and November16, 1992, and to areas of the primaryescapeway developed prior to March 30,1970 where separation of the belt andtrolley haulage entries from the primaryescapeway existed prior to November16, 1992.

Paragraph (f)(3) prohibits certainequipment from the primary escapeway.Paragraphs (f)(4) and (f)(5) deal with fire

protection for mobile equipment that ispermitted in the primary escapeway andparagraph (f)(6) addresses a specificcircumstance when mobile equipmentmay operate in a primary escapewaywithout a fire suppression system.Paragraph (f)(7), a provision added tothe proposed language in response tocomments, allows the use of designatedemergency vehicles or ambulances inthe primary escapeway.

One commenter suggested that thefinal rule should not provide anexception for all areas where separationof the primary escapeway from the beltand trolley haulage entry does not exist.The commenter recognized, however,that Congress granted an exemptionfrom separation requirements for areasof the primary escapeway developedprior to March 30, 1970, the effectivedate of the Act. The intent of theproposal was to provide an exemptionfrom the requirements of proposedparagraphs (f)(3) through (f)(6) for thesesame areas. The commenter points outthat the proposal would have extendedthe exemption to other areas of theprimary escapeway where, for onereason or another, separation did notexist on November 16, 1992, theeffective date of the existing rule. Thefinal rule modifies the proposal toclarify that the exemption only appliesto those areas of the escapeway thatwere developed prior to March 30, 1970and where separation did not exist onNovember 16, 1992.

Another commenter correctlyinterpreted proposed paragraph (f)(2) asextending the requirement that limitsthe types of equipment permitted inprimary escapeways to areas of the minedeveloped prior to November 16, 1992.The commenter stated that the proposedregulation would pose great cost to theindustry with no appreciable safetybenefit derived. A review of the firehistory relative to both stationary andmobile equipment indicates that firescan and do occur on this equipment.Mobile equipment by design is intendedto provide flexibility in movement andis capable of operating anywhere in themine. Although the accident reports donot specify whether the mobileequipment that caught fire was in theprimary escapeway when the firestarted, it is reasonable to conclude thatat least some of these fires did occur inthe primary escapeway. MSHAcontinues to believe that given theimportance of the primary escapeway tothe safety of miners, the extension of therequirements for operation of equipmentin the primary escapeway isappropriate.

Paragraph (f)(3) lists the equipmentthat is not permitted in the primary

escapeway. Under paragraph(f)(3)(i) ofthe final rule, operating dieselequipment without an automatic firesuppression system is prohibited in theprimary escapeway unless it is attended,except as provided in paragraphs (f)(6)and (f)(7). One commenter stated thatattended diesel equipment with amanual fire suppression system presentsno fire hazard. Another commentersuggested that unattended dieselequipment should be prohibited. Whendiesel equipment is operated in theprimary escapeway and is properlyattended and equipped with a manualfire suppression system, the equipmentoperator can immediately respond to afire, and the safety afforded by theexisting standard is maintained. If themachine is shut off, however,attendance is not necessary. Whendiesel equipment is to be operatedunattended, an automatic system isrequired to protect against fire.

One commenter stated that‘‘attended’’ should be interpreted tomean that the operator is on or withinsight of the vehicle. Another commenterurged that the standard be clarified torequire that the operator be at thecontrols of the equipment. For thepurposes of § 75.380(f), by ‘‘attended’’MSHA means that the equipmentoperator would be on the mobileequipment or immediately adjacent tothe equipment and be capable ofactivating the fire suppression systemimmediately in the event of a fire.

The existing standard permitsequipment to be in the escapeway forpurposes of transporting miners andmaterials and for maintaining theescapeway but does not expresslyprohibit the haulage of coal in theprimary escapeway. As a matter ofclarification, the final rule specificallyprohibits coal haulage in the primaryescapeway unless incidental to cleanupand maintenance of the escapeway. Onecommenter supported the proposedprohibition of coal haulage noting thatcoal haulage would provide a readysource of fuel to a machinery-initiatedfire. Several commenters expressed aconcern that incidental coal haulageassociated with cleanup andmaintenance of the primary escapewaywould be prohibited under the proposedstandard. Cleanup and maintenance ofthe primary escapeway must bepermitted. Therefore, the final rulemodifies the proposal to permit mobileequipment to haul coal if incidental tocleanup and maintenance of the primaryescapeway.

Paragraph (f)(3)(iii) prohibitscompressors in the primary escapewayexcept as provided in subparagraphs(f)(3)(iii) (A) through (C). Subparagraph


(A) allows compressors necessary tomaintain the escapeway in safe,travelable condition; (B) allowscompressors that are components ofequipment such as locomotives androck dusting machines; and, (C) allowscompressors of less than fivehorsepower due to the limited firehazard associated with their operation.

One commenter described an incidentinvolving a compressor in an intakeairway, which was located in a fireproofenclosure but was improperlyventilated. According to the commenter,smoke and contaminants spreadthroughout the intake entry and reachedthe section, which was then evacuated.This illustrates the importance ofproviding adequate protection from thepossible spread of smoke andcontaminants associated withcompressor fires or overheating.

Paragraph (f)(3)(iv) of the final ruleadds battery chargers to the equipmentincluded in the proposal that ispermitted in the primary escapewayprovided it is located on or near aworking section and is moved as thesection advances or retreats. In all otherrespects, paragraph (f)(3)(iv) of the finalrule adopts the proposal. Underparagraph (f)(3)(iv), undergroundtransformer stations, battery chargingstations, substations, and rectifierscannot be located in the primaryescapeway except: (A) where necessaryto maintain the escapeway in safe,travelable condition; and (B) batterychargers and rectifiers and powercenters with transformers that are eitherdry-type or contain nonflammableliquid, provided they are located on ornear a working section and are movedas the section advances or retreats. Thefirst exception allows work to beperformed in the primary escapeway toassure its integrity. The second providesfor the locations of the describedequipment at or near working sectionsif the equipment moves with thesection. Equipment at or near workingsections will normally be within a fewcrosscuts of the working face. In manycases, particularly with battery chargers,there may be no practical alternative tolocating this equipment in theescapeway. In addition, § 75.340provides additional protection whenusing underground electricalequipment.

Paragraph (f)(3)(v) of the final ruleadopts the proposal and prohibits waterpumps from being in the primaryescapeway except as provided underparagraphs (f)(3)(v)(A) through(f)(3)(v)(F). The pumps that arepermitted in the primary escapeway arethe same ones that are excepted fromthe requirements of § 75.340 due to the

low potential for fire associated withtheir operation. They include: waterpumps necessary to maintain theescapeway in safe, travelable condition;submersible pumps; permissible pumpsand associated permissible switchgear;pumps located on or near a workingsection that are moved as the sectionadvances or retreats; pumps installed inanthracite mines; and small portablepumps. While the existing rule refers tothe electrical equipment described in§ 75.340 (a) and (b)(1), the final rule,like the proposal, lists the affectedequipment for the convenience of thereader. Like § 75.340, paragraph (f)(3)(v)applies to water pumps and emulsionpumps when they are located on or nearthe working section and are moved asthe section advances or retreats. Onecommenter agreed that pumps may benecessary to maintain and rehabilitatethe primary escapeway but suggestedthat a time limit be placed on the lengthof time the pump is allowed to remainin the escapeway. MSHA believes thatspecific conditions at the mine willgovern the amount of time required forany necessary pumping. Therefore,MSHA has not included the suggestionin the final rule since the decisionrelative to time must be made on a case-by-case basis, as appropriate.

Paragraph (f)(4) of the final ruleadopts MSHA’s proposal with onechange. As proposed, paragraph (f)(4)would have required the use of firesuppression systems on mobileequipment operated in the primaryescapeway, and would have allowedexceptions for continuous miners and asprovided in § 75.380(f)(5)and (f)(6). Thefinal rule adds an additional exceptionfor emergency vehicles or ambulancesas provided in § 75.380(f)(7). Unlike theexisting standard, the final rule inparagraph (f)(4) permits certain mobileequipment operated in the primaryescapeway to be protected with amanual fire suppression system insteadof an automatic system, provided it iscontinuously attended by a persontrained in the use and operation of thefire suppression system. MSHA believesthat when a piece of equipment isoperated in the primary escapeway andis properly attended and equipped witha manual fire suppression system, theequipment operator can immediatelyrespond to the situation, and the safetyafforded by the existing standard ismaintained.

One commenter stated that noelectrical, battery or diesel equipment,or other equipment such as compressorsshould be allowed in the primaryescapeway, except for the purpose ofmaintenance of the escapeway, and thatthis equipment should have an

appropriate fire suppression system.Because travel in the escapeway incertain mining systems is essential forsafety given the design of the miningsystem used, the recommendation of thecommenter has not been adopted in thefinal rule. Instead, the final ruleprovides that certain types of miningequipment can be operated in theprimary escapeway provided the safetyprecautions set out in the standard arefollowed. One commenter stated thatthe rule should only apply to mobileequipment which is operated in theprimary escapeway, since equipmentnot operating presents little or nohazard. MSHA agrees and hasincorporated this clarification into thefinal rule.

Commenters indicated that it issometimes necessary to withdraw faceequipment, such as continuous miners,roof bolting machines and shuttle cars,into the primary escapeway for a shortdistance beyond the loading point. Theequipment is sometimes parked and leftthere on down shifts or between shifts.MSHA notes that, as clarified, the finalrule does not prohibit this practice.Because the equipment would beattended when operated and is providedwith manual fire suppression, theequipment may be operated in theprimary escapeway.

Following promulgation of theexisting rule, some persons construedthe requirement for an automatic firesuppression system to apply to electricface equipment. As explained in thepreamble to the proposal, this was notthe intent of MSHA. To clarify its intent,MSHA issued Program Policy Letter No.P92–V–4 on November 16, 1992,addressing the operation and location ofequipment in primary escapeways.Under existing regulations in SubpartL—Fire Protection, face equipment isrequired to be protected by a manualfire suppression system. The final rulerecognizes and generally conforms withthis requirement. Other than for anexception to permit a situation such asthe movement of continuous miningmachines between sections without acontinuous water supply, the final rulerequires that when face machinery,equipped with a manual firesuppression system, is operated in theprimary escapeway, it must be attendedby a person trained in the properfunction and use of the fire suppressionsystem. The continuous miningmachine exception recognizes that thefire suppression system for thecontinuous mining machine often relieson a water supply that may beimpracticable to provide duringequipment moves.


The final rule requires in paragraph(f)(4) that with exceptions forcontinuous mining machines and asprovided in paragraphs (f)(5), (f)(6), and(f)(7), each piece of mobile equipmentoperated in primary escapeways shall:(1) be equipped with manually operatedfire suppression systems installed incompliance with §§ 75.1107–3 through75.1107–16 and be attendedcontinuously; or (2) be equipped withan automatic fire suppression systemthat is capable of both automatic andmanual activation and installed incompliance with §§ 75.1107–3 through75.1107–16.

Under paragraph (f)(5) of the finalrule, personnel carriers and smallpersonnel conveyances designed andused solely for the transportation ofpersonnel and small hand tools can beoperated in the primary escapeway ifeither of the requirements underparagraphs (i) or (ii) are met. Paragraph(i) requires a multipurpose dry chemicaltype automatic fire suppression systemcapable of both manual and automaticactivation. Paragraph (ii) provides analternative for a class of small, batterypowered, golf cart type, equipment usedfor transport of persons and small handtools. In this case, fire extinguishersmay be used in lieu of a fire suppressionsystem.

Commenters questioned the need forautomatic systems on the class ofequipment consisting of small, batterypowered, golf cart type equipment. Onecommenter suggested that a manual firesuppression system should be accepted.After a review of the issue, MSHA hasconcluded that some types of mobileequipment present a very limited firehazard. In the case of small, batteryoperated, golf cart type, conveyancesdesigned and used for the transport ofpersonnel and small hand tools,considering the limited hazard, atrained operator provided with two 10pound multi-purpose dry chemical fireextinguishers is equivalent in protectionto a fire suppression system.Accordingly, as an alternative underparagraph (ii), small battery powered,golf cart type, equipment may beoperated in the primary escapeway ifprovided with two 10 pound multi-purpose dry chemical fire extinguishers.Unlike diesel powered equipment, thegolf cart type of equipment is shut offwhen not operating and, therefore,attendance is not an issue. The 10pound units are standard sizeextinguishers and are appropriate forthe equipment involved.

The system used in accordance withparagraph (i) must be suitable for theintended application and listed orapproved by a nationally recognized

independent testing laboratory. Thelanguage was proposed as twoparagraphs but has been combined inthe final rule under paragraph (i) and analternative has been added as paragraph(ii). The types of machinery which fallunder paragraph (f)(5) are not requiredto meet the additional requirements of§§ 75.1107–3 through 75.1107–16. Forexample, it would be impractical andwould not enhance safety to apply theminimum dry chemical poundagerequirements of § 75.1107–9 to smallequipment designed and used solely forpersonnel and small hand tools.

During informational meetings, it wassuggested that the term ‘‘dry chemical’’would be more accurate and appropriatethan the term ‘‘dry powder’’ used in theexisting standard. Like the proposal, thefinal rule adopts this language. MSHAreceived no comments on this proposedrevision.

Paragraph (f)(6) of the final ruleprovides an exception to the generalrequirement and allows mobileequipment not provided with a firesuppression system to operate in theprimary escapeway if no persons areinby other than persons directlyengaged in the use or moving of theequipment. This provision of the finalrule allows for the necessary movementof face equipment, such as betweensections.

One commenter stated that theexemption provided in (f)(6) should beexpanded to allow equipment that doesnot have a fire suppression system to berelocated provided monitoringequipment is utilized for carbonmonoxide or smoke and two-waycommunication is available to notifyappropriate persons. The final rule doesnot adopt this suggestion. Duringmoves, equipment is often laboring atmaximum capacity and there can beseveral machines operatingsimultaneously. Under these conditions,equipment fires can develop quicklyand the products of combustion wouldbe carried to inby workers by theventilating current. By permitting onlyworkers who are directly engaged in theoperation or movement of theequipment, the final rule prevents otherworkers from being exposed to thehazards of a fire on the equipment beingmoved. Workers operating or engaged inmoving the equipment will be in aposition to quickly identify the hazardand take necessary action.

Another commenter objected to theprovision stating that fire suppressionshould be required on all equipment inthe primary escapeway. This suggestionhas not been adopted in the final rule.MSHA does not agree that firesuppression is needed when no persons

are inby or downstream of theequipment being moved. MSHA hasconcluded that either these machinesshould be equipped with firesuppression, or fire extinguishers as in(f)(5)(ii), or no persons should be inbythe location where the equipment isbeing operated except those personsdirectly engaged in the operation ormovement of the equipment.

Another commenter suggested thatthe wording of (f)(6) could be read toallow miners to work on a longwall facewhile equipment not equipped with firesuppression is operated anywhere in theprimary escapeway. This is notpermitted by the standard. By includingthe phrase, ‘‘* * * except those personsdirectly engaged in using or moving theequipment’’, the persons affected areonly those persons in the immediatevicinity of the machine. With nopersons working inby, the use ofmachinery without a fire suppressionsystem would not expose persons to thehazard of toxic gases and fumes from afire on the equipment. The languagealso would not permit persons tooperate mobile equipment without a firesuppression system in the primaryescapeway while miners aredownstream working on a longwall face.The controlling factor is whether thepersons inby are directly engaged inusing or moving that particular piece ofequipment. If they are, and no one elseis inby, the equipment may be operatedwithout a fire suppression system. Forexample, when moving a longwallshield, no one would be permitted to beinby the machine being used to movethe shield if the machine is notprovided with a fire suppression systemexcept those persons moving the shield.This would include miners operatingother pieces of equipment to move othershields.

Paragraph (f)(7) modifies the existingrule to include a new exemption to therequirement that mobile equipmentoperated in primary escapeways have afire suppression system. Paragraph (f)(7)permits mobile equipment designatedand used only as emergency vehicles orambulances to operate in the primaryescapeway without fire suppressionsystems. It was suggested to MSHA thatcertain types of emergency equipment,such as diesel powered ambulances,should be exempt from the requirementsfor fire suppression systems. Commentswere received suggesting thatambulances should be exempt becausespace is extremely limited on thesevehicles and because they are usedinfrequently. MSHA recognizes thepotential benefit in the use of this typeof equipment. Another commenterobjected, foreseeing potential abuses of


the exemption by mine operators whowould designate equipment asambulances but use it as ordinaryequipment. The final rule permitsemergency vehicles to be operated inthe primary escapeway without firesuppression systems only when thisequipment is used only for medicalemergencies.

This existing rule requires inparagraph (i)(2) that mechanical escapefacilities be provided and maintainedfor, ‘‘. . . each slope that is part of adesignated escapeway that is eitherinclined 18 degrees or more from thehorizontal or is inclined 9 degrees ormore from the horizontal and is greaterthan 1,000 feet in length.’’ Duringinformational meetings, MSHA becameaware of a concern that existingparagraph (i)(2) would permit slopes ofsignificant length and inclination toexist without any mechanical escapefacilities. An example would be a slopeof 900 feet inclined less than 18 degreesfrom the horizontal. It was suggestedthat such a slope could be particularlydifficult for passage of injured personsunder cold and icy conditions ifmechanical escape facilities were notprovided. In light of this concern,MSHA proposed to require thatmechanical escape facilities be providedand maintained from the coal seam tothe surface for each slope that is part ofa designated escapeway and is inclinedmore than 9 degrees from the horizontal.The final rule adopts the proposal.

One commenter objected to proposedparagraph (i)(2) indicating that facilitiesare unnecessary in low angle slopeswhich are of short length. Othercommenters believed that the 1992standard was appropriate. Anothercommenter indicated support for theproposal as a way to enable persons toescape quickly in an emergency. Thiscommenter also noted that escape canbe very difficult in icy winter conditionsin some slopes. After consideration ofthe comments received, MSHAconcludes that the proposal wasappropriate and the final rule adoptsthis aspect of the proposal.

One commenter suggested thatproposed paragraph (i)(2) could beinterpreted as requiring mechanicalescape facilities for slopes that occurnaturally underground. It was notMSHA’s intent to apply paragraph (i)(2)to slopes other than from the coal seamto the surface. The final rule clarifiesthis and requires that mechanical escapefacilities be provided for each slopefrom the coal seam to the surface that ispart of a designated escapeway and isinclined more than 9 degrees from thehorizontal.

Section 75.382 Mechanical EscapeFacilities

Because an escapeway route cansometimes be very long, the most safe,direct and practical route to the surfacecan sometimes involve the use of amechanical escape device such as anautomatic elevator or similar, but lesssophisticated, device. Section 75.382contains the requirements formechanical escape facilities installed inescapeways under § 75.380 and§ 75.381. The final rule contains a newrequirement for certification of escapefacility examinations, proposed asparagraph (g). The final rule does notretain the other proposed changes,paragraphs (h) and (i), that would haveadded recordkeeping andcountersigning requirements.

Under paragraph (g) of the final rule,the designated examiner certifies bydate, time, and initials that themechanical escape facilitiesexamination required by paragraph§ 75.382(c) was performed. Thecertification must be located at or nearthe facility examined. Certification haslong been an accepted practice in themining industry for assuring that arequired examination has beencompleted. One commenter agreed thatcertification is necessary and supportedthe revision. The commenter indicatedthat the facilities are often designated asescapeways and therefore there shouldbe some assurance that the facilitieshave been examined and are ready foruse. Also, in the case of mechanicalescape facilities, if certification is notprovided, precious time could be lost asthe escape facility is tested prior to useto determine if it is functional and safe.

Under the proposed paragraphs (h)and (i), a record would have had to bemade of the examination of the escapefacility performed in accordance with§ 75.382 (c). The results of theexamination would be included in arecord, including any deficiency foundalong with the corrective actions takento correct the condition. One commentersupported the revision requiring recordsof deficiencies found duringexaminations as well as a record ofcorrective actions. Other commentersobjected to additional records, notingthat they would not enhance safety.After review of the comments, MSHAhas concluded that certification willachieve the intended objective ofassuring the safety of mechanicalescape. Accordingly, the recordkeepingrequirements proposed as paragraphs(h) and (i) are omitted from the finalrule.

One commenter stated that manycompanies utilize mobile escape

facilities to cover more than one mineif the mines are located in closeproximity. The commenter believed thatsuch an arrangement was notconsidered in the countersigningprovisions of the proposal and stated,‘‘The effort required to go to each mineevery week and track down the mineforeman would be burdensome andunnecessary.’’ Paragraph (c) of theexisting rule requires a weeklyexamination and a weekly test in whichthe hoist must be run through onecomplete cycle of operation todetermine that it is operating properly.The final rule requires certification to becompleted by the examiner. Asindicated above, MSHA has concludedthat certification will achieve theintended objective of assuring that theexaminations have been conducted.

Additional comments were receivedrecommending further modificationsand additions to § 75.382. For example,a commenter recommended 2-waycommunication capability, withsupplies and a holding area at theescape facility. These types ofcomments related to issues outside thescope of the rulemaking and were notaddressed. Another commenter wouldhave MSHA reinstate language from anearlier rule, alleging a reduction inprotection. MSHA does not believe thatthere is a reduction in protection. Also,the final rule did not propose to changethe existing requirement that thecommenter claimed reduced protection,i.e., that a person trained to operate themechanical escape facility always shallbe available. MSHA notes that this issueis outside the scope of the rulemaking.

Section 75.383 Escapeway Maps andDrills

When a fire, explosion or otheremergency necessitates an immediateevacuation of a mine the designatedroute for miners to leave the mine is theescapeway. During a mine fire,passageways, even those designated asescapeways, can become smoke filledand the ability to see can be drasticallyreduced. Therefore, it is vitallyimportant that miners know the route oftravel through the escapeway. Section75.383 provides for the posting ofescapeway maps so that they areavailable for miners to study and useduring an emergency, if necessary.Section 75.383 also provides for minersto be trained in the escape route throughescapeway drills. Escapeway drills inmines are similar to fire drills in schoolsand high rise buildings.

Existing paragraphs (a) and (b)(1) of§ 75.383 deal with the escapeway mapand drill requirements in areas wheremechanized mining equipment is being


installed or removed. Based oncomments received, the final rulecontains 2 revisions to the proposal. Thefirst allows the mine map to be readilyaccessible as an alternative to posting.The second requires that miners whoare underground when any change ismade to the escapeway map beimmediately notified of the change.These revisions to the proposal arediscussed below.

One commenter supported therequirements of (a) and (b)(1) noting thehazards and activities wheremechanized mining equipment is beinginstalled or removed. Anothercommenter stated that the requirementthat the map be ‘‘posted’’ is impracticalin some mines. The commenter statedthat the rule should simply require thatthe map be maintained on the section toallow the map to be maintained in amap tube, or be covered. Thecommenter also indicated that a maptube could aid miners in a rapid escapesince the map and tube could easily betaken with the miners during theescape. MSHA agrees that themaintenance of a posted map could bedifficult in some conditions such as inwet or very low height mines.Accordingly, the final rule provides anoption wherein the map may be eitherposted or be maintained in a locationreadily accessible to all miners. Inspecifying ‘‘readily accessible’’ MSHAintends that all miners be made awareof the map location and have access toreview the map at any time. As anexample, a map secured in a locked toolchest would not be acceptable.

One commenter objected to paragraph(a) in two respects. First, according tothe commenter, the standard does notrequire maps to show the revisedescapeway routes until the end of theshift on which the changes are made.The commenter believes that changesare projected in advance and thereforethe maps should be updatedimmediately. Second, the commenterindicated that the requirement thatminers must be informed of the changesbefore entering the mine does notaddress affected miners alreadyunderground. Many changes withinescapeways are not known or plannedwell in advance. Often, such revisionsare in response to changing conditionsunderground. MSHA does not believethat allowing a portion of one shift is anexcessive amount of time to update themaps. MSHA does agree, however, thatchanges to the escapeways should beimmediately brought to the attention ofall miners who are underground at thetime of a change. Accordingly, the finalrule specifies that all affected minersalready underground must be

immediately notified of the change. Thiswill assure that all affected miners areaware of the change from the time thechange is implemented.

While agreeing that each miner’sfamiliarity with escapeways isimportant, one commenter stated thatrequiring travel by foot in theescapeways could cause undue physicalstress to some miners in low or steeplypitching seams. The commentercontinued that the desired result couldbe obtained by requiring fullparticipation in drills wheretransportation is provided and fullparticipation in drills wheretransportation is not provided, unlessthat escapeway is equipped with acontinuous, directional life line. MSHAnotes that the standard does not requiretravel on foot. Transportation may beused for escapeway drills provided thatthe purpose of the standard can beachieved. That purpose is to assure thatminers are familiar with the escapewayroutes and, as specified in (b)(4), beforeor during practice escapeway drills,miners shall be informed of thelocations of fire doors, check curtains,changes in the routes of travel, andplans for diverting smoke fromescapeways. Traveling an escapeway ina completely enclosed mantrip, suchthat the route could not be observed,would not meet the requirement. As tothe concept of exempting drills in thealternate escapeway where mechanizedtransportation is unavailable if adirectional lifeline exists, MSHAbelieves that certain minimumspecifications for lifelines would beneeded before such a compliancealternative could be considered. Thiswould expand the scope of thisrulemaking beyond the proposal.

One commenter suggested anexpansion of 75.383 to require:directional life lines in bothescapeways; communications in bothescapeways; numbering of all stoppingsalong escapeways; additional SCSRcaches; hard hat stickers depictingescapeways and SCSR donningprocedures; and other measures. Whilemany of the suggestions may have merit,they are outside the scope of thisrulemaking.

In the proposal, MSHA solicitedcomments on a concept to allowindividual miners to opt out ofescapeway drills for health reasons. Onecommenter indicated that a number ofadditional requirements would beneeded to assure that any miners optingout would still remain familiar with theescapeways. After considering thecomments received, MSHA has notincluded an option for miners to opt outof the escapeway drills. As one

commenter pointed out, it is essentialthat each miner be familiar with theescapeways. MSHA concludes that anumber of accommodations can bemade to provide assistance to any minerexperiencing difficulty during drills. Asdiscussed above, mobile equipment maybe used provided that the conveyance isnot so enclosed that miners cannotobserve the route. Operators can allowadditional time for miners who mayencounter difficulty. Also, assistancecan be provided by other miners,particularly in difficult areas such asunusually steep grades. Such assistancewould likely also be needed in an actualemergency and therefore the drillswould be particularly instructive to allthe miners participating in the drills.

MSHA believes that for areas wheremechanized mining equipment is beinginstalled or removed, providingescapeways and posting mapsidentifying these escapeways andconducting the drills specified in thestandard are essential to maintainsafety. These requirements help toassure that miners are familiar withescape routes so that should urgentescape become necessary, they canreach the surface as quickly as possible.

Section 75.384 Longwall andShortwall Travelways

Modern mining methods includeremoving large blocks of coal in onecontinuous operation along a wallwhich can be several hundred feet long.This method is known as longwall orshortwall mining. To avoid trappingminers in the face area without a meansof escape in the event of an emergency,there is a need to have a travelway onthe side of the block of coal opposite theescapeways. Section 75.384 addressesthe requirements for a travelway on thetailgate side of a longwall or shortwall,the location and marking of thetravelway, and procedures to followduring a blockage of the travelway.

MSHA proposed no changes to theexisting rule. Likewise, the final rulemakes no changes to the existing rule.The preamble to the proposal explainedthat MSHA had received commentsuggesting that the existing rule bemodified to provide for additionalinvolvement by miners when a roof fallor other blockage occurs that preventstravel in the tailgate travelway. MSHAbelieves that the existing proceduresand regulations appropriately addressthe hazards and provide a sufficientopportunity for input and involvementfor all interested parties. The preambleto the proposal contains a discussion ofthe existing procedures and regulations.

One commenter recommended severaladditions to existing § 75.384 while


agreeing that maintenance of a tailgatetravelway is essential. Therecommendations included requiringthe tailgate travelway to be ventilated byintake air. The commenter noted thatseveral mines presently ventilate in thismanner, providing intake air splits atboth headgate and tailgate. While thissystem has certain advantages, it is notfeasible or practical in all cases.

Section 75.388 Boreholes in Advanceof Mining.

Areas of a mine, or of an adjacentmine, can be located in close proximityto an advancing working place but canbe inaccessible for a variety of reasons.These inaccessible areas of a mine canpresent hazards when mining proceedsinadvertently or improperly into theseareas. Inaccessible areas may containpotentially dangerous accumulations ofgases or water, which could result inexplosions or inundations. To protectagainst these hazards, § 75.388 requiresoperators to drill boreholes into the coalbefore they extract it. In this manner,the operator can determine whethermining, if continued, will penetrate anarea where unknown hazards may bepresent. Boreholes are not requiredwhen the area toward which mining isadvancing is accessible and is properlyexamined.

The final rule revises requirements forthe drilling of boreholes in advance ofmining. It requires boreholes to bedrilled in both ribs of advancingworking places unless an alternativedrilling plan is approved by the districtmanager in accordance with existingparagraph (g) of this section. Existingparagraph (c) requires that boreholes bedrilled in at least one rib of advancingworking places described in § 75.388 (a).Although MSHA did not intend anychange in promulgating the existinglanguage, comments indicated that someconfusion existed. To address this issue,MSHA proposed to revise the existingstandard and adopt language similar tothe regulation which was in effect priorto 1992. The proposed revisions to§ 75.388 (c) would have required boreholes to be drilled in one or both ribsof advancing working places describedin § 75.388(a), ‘‘ . . . as may benecessary for adequate protection ofminers in such working places.’’

Several comments were received inresponse to the proposal. Onecommenter indicated that the proposedrevision was unnecessary since the 1992standard adequately indicated that morethan one rib may need to be drilled.Another commenter stated that drillingone rib is always adequate sincerequired drilling in adjacent places willassure that the entire area is explored by

drilling. MSHA’s experience is thatworking places are seldom developed atthe same rate and some may lag bysignificant distances. In addition, entryor room centers are ordinarily in excessof the 20 foot drill hole depth specifiedin the standard. Thus, coverage over theentire width of the advancing section isnot always provided as suggested by thecommenter. Another example would bewhere an advance heading approachesan inaccurately mapped abandonedmine such that the unknown workingsare approached near the undrilledribline. An inundation could occur atthe undrilled ribline as the workingplace advanced. To address thesehazards, the final rule requires drillingof both ribs. If the workings were notdiscovered through drilling, multiplefatalities could result from inundationsof water, methane, or oxygen deficientatmosphere (black damp). Accidentssimilar to this scenario have occurredand resulted in inundations of water,methane, or irrespirable atmospheres.

One commenter noted that 38inundations of gases or water occurredbetween 1990 and 1994. MSHA notesthat this number represents only thoseaccidental cut-throughs which resultedin inundations. It should be noted thatnumerous additional accidental cut-throughs have occurred which did notresult in inundations. Each of theseadditional accidental cut-throughsdemonstrates the potential for a seriousor fatal accident. The commenter statedthat the number of inundations and thepotential for multiple fatalities warranta revision to the standard to requireboth ribs to be drilled. Similarcomments and examples were heardduring the public hearings. MSHAagrees.

MSHA concludes that in general, bothribs should be drilled; however, undersome circumstances drilling of both ribsmay be unnecessary. Moreover, MSHArecognizes that there are circumstanceswhere it would be unnecessary to drillboth ribs at all times. Thus, the finalrule requires that both ribs be drilledunless the district manager grantsapproval for an alternative drillingpattern under existing paragraph (g).Under existing paragraph (g), analternative drilling pattern may beapproved which may not requiredrilling of both ribs. As with other planswhich are subject to approval, requestsfor alternative drilling patterns will bereviewed on a case by case basis. Afterconsidering all comments receiveddiscussing this issue, MSHA hasconcluded that the hazard of aninundation is properly addressed by thefinal rule which retains sufficientflexibility for a site specific drilling

pattern if the district manager can besatisfied that the alternative is suitableto the particular circumstances.

Another comment suggested that theminimum distances which triggerdrilling as specified in § 75.388 (a)(1),(a)(2), and (a)(3) be revised to 100, 500,and 500 feet, respectively. In support ofthe suggestion, the commenter notedfactors such as inaccurate old minemaps, unmapped mining over-boundaryor outside the legal limits, lost maps orunknown mines, and less than diligentresearch by some operators. Theminimum drilling distances inparagraph (a) were not proposed forrevision and the final rule does notaddress them. However, it is importantto note that the distances specified arethe minimum at which drilling mustbegin if there is reasonable confidencein the position of the old workings. Thedistances specified provide a safetyfactor to account for slight miningoverruns, mapping errors, smalldeliberate omissions, and similar factorsin cases where the position of the oldworkings are known with reasonablecertainty. In cases where old workingsare known to exist but the position isunknown or known with littleconfidence, drilling would be necessaryin excess of the minimum distancesspecified in (a) to assure compliancewith the standard.

Section 75.389 Mining intoInaccessible Areas

While § 75.388 addresses the need toidentify inaccessible areas to avoidaccidentally drilling into an areacontaining a possible hazardousenvironment, § 75.389 establishesprocedures for drilling into aninaccessible area that has beenidentified. Section 75.389 requires aseparate plan be developed andapproved for drilling into inaccessibleareas. Paragraph (c) of the final ruleclarifies that the requirements of§ 75.389(c)(1), (c)(2) and (c)(3) do notapply to routine mining-throughoperations that are part of a retreatsection ventilation system approved inaccordance with § 75.371(f) and (x). Thefinal rule retains the proposed language.

The preamble to the proposal pointedout that, based on comments receivedduring informational meetings and otherdiscussions, differing interpretations ofthe application of existing § 75.389existed. Some persons were interpretingparagraph (c) as requiring, for example,the mine to be evacuated during thebreak-through of a pillar split in aretreating section. However, paragraphs(a) through (c) of § 75.389 were intendedto apply during mining-throughoperations in areas subject to § 75.388


where hazards and potential hazardsmay be unknown. The final rule revisesexisting § 75.389(c) by adding anexception for routine mining-throughoperations that are a part of a retreatmining system approved in the mineventilation plan. In some circumstances,the mining through occurs duringroutine mining into an area which iscovered by an approved mineventilation plan. In this case, thepotential hazards have already beenaddressed in the mine ventilation plan.Requiring the operator to submitduplicate plans would not result in any

safety benefit; therefore, the level ofsafety provided by the existing standardis maintained.

Petitions for Modification

Operators with petitions formodification that involve the standardsrevised in this rulemaking need todetermine the status of those petitionsbefore the effective date of the rule. Ifthere are sections of this rule that arerenumbered but remain substantivelyunchanged from the existing standards,operators with modifications granted forthese standards need not reapply.

However, operators with petitions formodifications granted for standards thathave been revised must comply with thenew rule on its effective date. Newpetitions for modification of the finalrule may be submitted under 30 CFRpart 44. If Agency assistance is needed,questions should be directed to theappropriate MSHA district office.

Derivation Table

The following derivation table liststhe number of each final standard andthe number of the existing standardfrom which it is derived.

New section Old section

75.301 .................................................................................................................................................................. Partly new, 75.301.75.310(a)(3) ......................................................................................................................................................... Partly new, 75.310(a)(3).75.310(a)(4) ......................................................................................................................................................... Partly new, 75.310(a)(4).75.310(c) .............................................................................................................................................................. Partly new, 75.310(c).75.310(c)(1) ......................................................................................................................................................... Partly new, 75.310(c).75.310(c)(2) ......................................................................................................................................................... 75.310(c).75.310(c)(3) ......................................................................................................................................................... New.75.310(c)(4) ......................................................................................................................................................... Partly new, 75.310(c).75.310(c)(4)(i) ...................................................................................................................................................... 75.310(c)(1).75.310(c)(4)(ii) ..................................................................................................................................................... 75.310(c)(2).75.310(c)(5) ......................................................................................................................................................... New.75.311(d) ............................................................................................................................................................. Partly new, 75.311(d).75.312(a) ............................................................................................................................................................. Partly new, 75.312(a).75.312(b)(1) ......................................................................................................................................................... Partly new, 75.312(b)(1).75.312(b)(1)(i) ...................................................................................................................................................... New.75.312(b)(1)(ii) ..................................................................................................................................................... 75.312(b)(1) through(b)(1)(ii).75.312(c) .............................................................................................................................................................. Partly new, 75.312(c).75.312(d) ............................................................................................................................................................. Partly new, 75.312(d).75.312(f)(1) .......................................................................................................................................................... 75.312(f).75.312(f)(2) .......................................................................................................................................................... New.75.312(g)(1) ......................................................................................................................................................... Partly new, 75.312(g)(1).75.312(g)(2) ......................................................................................................................................................... New.75.312(g)(3) ......................................................................................................................................................... Partly new, 75.312(g)(3).75.312(h) ............................................................................................................................................................. Partly new, 75.312(h).75.313(a)(1) ......................................................................................................................................................... 75.313(a)(1).75.313(a)(2) ......................................................................................................................................................... 75.313(a)(2).75.313(a)(3) ......................................................................................................................................................... 75.313(a)(3).75.313(b) ............................................................................................................................................................. 75.313(b).75.313(c)(1) ......................................................................................................................................................... 75.313(c)(1).75.313(c)(2) ......................................................................................................................................................... Partly new, 75.313(c)(2).75.313(c)(3) ......................................................................................................................................................... Partly new, 75.313(c)(3).75.313(d)(1)(i) ...................................................................................................................................................... Partly new, 75.313(d)(1)(i).75.313(d)(1)(ii) ..................................................................................................................................................... Partly new, 75.313(d)(1)(ii).75.313(d)(2) ......................................................................................................................................................... Partly new, 75.313(d)(2).75.320(e) ............................................................................................................................................................. New.75.321(a)(1) ......................................................................................................................................................... Partly new, 75.321(a).75.321(a)(2) ......................................................................................................................................................... Partly new, 75.321(a).75.323(b)(1) ......................................................................................................................................................... 75.323(b)(1).75.323(b)(1)(i) ...................................................................................................................................................... 75.323(b)(1)(i).75.323(b)(1)(ii) ..................................................................................................................................................... Partly new, 75.323(b)(1)(ii).75.323(b)(1)(iii) .................................................................................................................................................... 75.323(b)(1)(iii).75.323(b)(2) ......................................................................................................................................................... 75.323(b)(2).75.323(b)(2)(i) ...................................................................................................................................................... 75.323(b)(2)(i).75.323(b)(2)(ii) ..................................................................................................................................................... 75.323(b)(2)(ii).75.323(c)(1) ......................................................................................................................................................... Partly new, 75.323(c)(1).75.323(d)(2)(i) ...................................................................................................................................................... Partly new, 75.323(d)(2)(i).75.325(d) ............................................................................................................................................................. Partly new, 75.325(d).75.330(c) .............................................................................................................................................................. New.75.332(a)(1) ......................................................................................................................................................... 75.332(a)(1).75.333(a) ............................................................................................................................................................. Partly new, 75.333(a).75.333(b)(1) ......................................................................................................................................................... Partly new, 75.333(b)(1).75.333(b)(3) ......................................................................................................................................................... Partly new, 75.333(b)(3).75.333(b)(4) ......................................................................................................................................................... Partly new, 75.333(b)(4).75.333(e)(1)(i) ...................................................................................................................................................... Partly new, 75.333(e)(1).75.333(e)(1)(ii) ..................................................................................................................................................... Partly new, 75.333(e)(2).75.333(h) ............................................................................................................................................................. 75.333(e)(1).75.334(e) ............................................................................................................................................................. Partly new, 75.334(e).



75.334(f)(3) .......................................................................................................................................................... Partly new, 75.334(f)(3).75.340(a) ............................................................................................................................................................. Partly new, 75.340(a).75.342(a)(4) ......................................................................................................................................................... Partly new, 75.342(a)(4).75.342(a)(4)(i) ...................................................................................................................................................... New.75.342(a)(4)(ii) ..................................................................................................................................................... New.75.342(a)(4)(iii) .................................................................................................................................................... New.75.344(a) ............................................................................................................................................................. Partly new, 75.344(a).75.344(a)(1) ......................................................................................................................................................... Partly new, 75.344(b)(1).75.344(a)(2) ......................................................................................................................................................... Partly new, 75.344(a)(1).75.344(a)(2)(i) ...................................................................................................................................................... 75.344(b)(2)(i).75.344(a)(2)(ii) ..................................................................................................................................................... 75.344(b)(2)(ii).75.344(b) ............................................................................................................................................................. Partly new, 75.344(a)(2).75.344(e) ............................................................................................................................................................. New.75.360(a)(1) ......................................................................................................................................................... Partly new, 75.360(a)(1).75.360(a)(2) ......................................................................................................................................................... New.75.360(b) ............................................................................................................................................................. 75.360(b).75.360(b)(1) ......................................................................................................................................................... Partly new, 75.360(b)(1).75.360(b)(3) ......................................................................................................................................................... Partly new, 75.360(b)(3).75.360(b)(4) ......................................................................................................................................................... Partly new, 75.360(b)(4).75.360(b)(6)(i) ...................................................................................................................................................... Partly new, 75.360(b)(6).75.360(b)(6)(ii) ..................................................................................................................................................... Partly new, 75.360(b)(6).75.360(b)(8) ......................................................................................................................................................... New.75.360(b)(9) ......................................................................................................................................................... New.75.360(b)(10) ....................................................................................................................................................... New.75.360(e) ............................................................................................................................................................. 75.360(f).75.360(f) .............................................................................................................................................................. Partly new, 75.360(g).75.360(g) ............................................................................................................................................................. Partly new, 75.360(h).75.362(a)(1) ......................................................................................................................................................... Partly new, 75.362(a)(1).75.362(a)(2) ......................................................................................................................................................... New.75.362(c)(1) ......................................................................................................................................................... Partly new, 75.362(c)(1).75.362(c)(2) ......................................................................................................................................................... 75.362(c)(2).75.362(d)(1)(i) ...................................................................................................................................................... New.75.362(d)(1)(iii) .................................................................................................................................................... Partly new, 75.362(d)(1)(ii).75.362(d)(2) ......................................................................................................................................................... Partly new, 75.362(d)(2).75.362(g)(1) ......................................................................................................................................................... New.75.362(g)(2) ......................................................................................................................................................... New.75.363 .................................................................................................................................................................. Partly new, 75.313, 75.361,

75.362.75.364(a)(1) ......................................................................................................................................................... Partly new, 75.364(a)(1).75.364(a)(2)(i) ...................................................................................................................................................... Partly new, 75.364(a)(2)(i).75.364(a)(2)(ii) ..................................................................................................................................................... Partly new, 75.364(a)(2)(ii).75.364(a)(2)(iii) .................................................................................................................................................... Partly new, 75.364(a)(2)(iii).75.364(a)(2)(iv) .................................................................................................................................................... Partly new, 75.364(a)(2)(iii).75.364(h) ............................................................................................................................................................. Partly new, 75.364(h).75.364(i) ............................................................................................................................................................... Partly new, 75.364(i).75.370(a)(3) ......................................................................................................................................................... Partly new, 75.370(a)(3).75.370(a)(3)(i) ...................................................................................................................................................... New.75.370(a)(3)(ii) ..................................................................................................................................................... 75.370(a)(3).75.370(a)(3)(iii) .................................................................................................................................................... Partly new, 75.370(a)(3).75.370(b) ............................................................................................................................................................. New.75.370(c)(1) ......................................................................................................................................................... Partly new, 75.370(b)(1).75.370(c)(2) ......................................................................................................................................................... 75.370(b)(2).75.370(f) .............................................................................................................................................................. Partly new, 75.370(e).75.370(f)(1) .......................................................................................................................................................... New.75.370(f)(2) .......................................................................................................................................................... Partly new, 75.370(e).75.370(f)(3) .......................................................................................................................................................... Partly new, 75.370(e).75.371(r) .............................................................................................................................................................. Partly new, 75.371(r).75.371(s) .............................................................................................................................................................. Partly new, 75.371(s).75.371(z) .............................................................................................................................................................. Partly new, 75.371(z).75.371(bb) ........................................................................................................................................................... Partly new, 75.371(bb).75.371(cc) ............................................................................................................................................................ Partly new, 75.371(cc).75.372(b)(3) ......................................................................................................................................................... Partly new, 75.372(b)(3).75.372(b)(19) ....................................................................................................................................................... New.75.372(b)(20) ....................................................................................................................................................... New.75.380(b)(1) ......................................................................................................................................................... 75.380(b)(1).75.380(b)(2) ......................................................................................................................................................... 75.380(b)(2).75.380(d)(3) ......................................................................................................................................................... Partly new, 75.380(d)(3).75.380(d)(4)(ii) ..................................................................................................................................................... Partly new, 75.380(d)(4)(ii).75.380(d)(4)(iii) .................................................................................................................................................... New.75.380(d)(4)(iv) .................................................................................................................................................... New.75.380(d)(5) ......................................................................................................................................................... Partly new, 75.380(d)(5).75.380(f) .............................................................................................................................................................. Partly new, 75.380(f)(1).75.380(f)(1) .......................................................................................................................................................... Partly new, 75.380(f)(1).75.380(f)(2) .......................................................................................................................................................... Partly new, 75.380(f)(1).



75.380(f)(3) .......................................................................................................................................................... Partly new, 75.380(f)(1).75.380(f)(4) .......................................................................................................................................................... Partly new, 75.380(f)(2).75.380(f)(5) .......................................................................................................................................................... Partly new, 75.380(f)(2).75.380(f)(6) .......................................................................................................................................................... New.75.380(f)(7) .......................................................................................................................................................... New.75.380(i)(2) .......................................................................................................................................................... Partly new, 75.380(i)(2).75.382(g) ............................................................................................................................................................. New.75.383(a) ............................................................................................................................................................. Partly new, 75.383(a).75.383(b)(1) ......................................................................................................................................................... 75.383(b)(1).75.388(c) .............................................................................................................................................................. Partly new, 75.388(c).75.389(c) .............................................................................................................................................................. New.75.389(c)(1) ......................................................................................................................................................... 75.389(c)(1).

Redesignation Table

The following redesignation table liststhe section number of the existing

standard and the section number of thefinal standard which contain revised

provisions derived from thecorresponding existing section.

Old section New section

75.310(a)(3) ....................................................................................................................................................... 75.310(a)(3).75.310(a)(4) ....................................................................................................................................................... 75.310(a)(4).75.310(c) ........................................................................................................................................................... 75.310(c).75.310(c) ........................................................................................................................................................... 75.310(c)(1).75.310(c) ........................................................................................................................................................... 75.310(c)(2).75.310(c) ........................................................................................................................................................... 75.310(c)(4).75.310(c)(1) ....................................................................................................................................................... 75.310(c)(4)(i).75.310(c)(2) ....................................................................................................................................................... 75.310(c)(4)(ii).75.311(d) ........................................................................................................................................................... 75.311(d).75.312(a) ........................................................................................................................................................... 75.312(a).75.312(b)(1) ....................................................................................................................................................... 75.312(b)(1), 75.312(b)(1)(ii).75.312(b)(1)(i) ................................................................................................................................................... 75.312(b)(1)(ii)(A).75.312(b)(1)(ii) ................................................................................................................................................... 75.312(b)(1)(ii)(B).75.312(c) ........................................................................................................................................................... 75.312(c).75.312(d) ........................................................................................................................................................... 75.312(d).75.312(f) ............................................................................................................................................................ 75.312(f)(1).75.312(g)(1) ....................................................................................................................................................... 75.312(g)(1).75.312(g)(3) ....................................................................................................................................................... 75.312(g)(3).75.312(h) ........................................................................................................................................................... 75.312(h).75.313(c)(2) ....................................................................................................................................................... 75.313(c)(2).75.313(c)(3) ....................................................................................................................................................... 75.313(c)(3).75.313(d)(1)(i) ................................................................................................................................................... 75.313(d)(1)(i).75.313(d)(1)(ii) ................................................................................................................................................... 75.313(d)(1)(ii).75.321(a) ........................................................................................................................................................... 75.321(a)(1).75.321(a) ........................................................................................................................................................... 75.321(a)(2).75.323(b)(1)(ii) ................................................................................................................................................... 75.323(b)(1)(ii).75.323(c)(1) ....................................................................................................................................................... 75.323(c)(1).75.323(d)(2)(i) ................................................................................................................................................... 75.323(d)(2)(i).75.325(d) ........................................................................................................................................................... 75.325(d).75.333(a) ........................................................................................................................................................... 75.333(a).75.333(b)(1) ....................................................................................................................................................... 75.333(b)(1).75.333(b)(3) ....................................................................................................................................................... 75.333(b)(3).75.333(b)(4) ....................................................................................................................................................... 75.333(b)(4).75.333(e)(1) ....................................................................................................................................................... 75.333(e)(1)(i).75.333(e)(1) ....................................................................................................................................................... 75.333(e)(1)(ii).75.334(e) ........................................................................................................................................................... 75.334(e).75.334(f)(3) ........................................................................................................................................................ 75.334(f)(3).75.340(a) ........................................................................................................................................................... 75.340(a)75.340(a)(1) ....................................................................................................................................................... 75.340(a)(1)(i).75.340(a)(2) ....................................................................................................................................................... 75.340(a)(1)(ii).75.340(a)(3) ....................................................................................................................................................... 75.340(a)(1)(iii).75.340(a)(3)(i) ................................................................................................................................................... 75.340(a)(1)(iii)(A).75.340(a)(3)(ii) ................................................................................................................................................... 75.340(a)(1)(iii)(B).75.340(a) ........................................................................................................................................................... 75.340(a)(2).75.340(a)(1) ....................................................................................................................................................... 75.340(a)(2)(i).75.340(a)(2) ....................................................................................................................................................... 75.340(a)(2)(ii).75.342(a)(4) ....................................................................................................................................................... 75.342(a)(4).75.344(a) ........................................................................................................................................................... 75.344(a).75.344(a)(1) ....................................................................................................................................................... 75.344(a)(2).75.344(a)(2) ....................................................................................................................................................... 75.344(b).75.344(b)(1) ....................................................................................................................................................... 75.344(a)(1).75.344(b)(2) ....................................................................................................................................................... 75.344(a)(2).75.344(b)(2)(i) ................................................................................................................................................... 75.344(a)(2)(i).


Old section New section

75.344(b)(2)(ii) ................................................................................................................................................... 75.344(a)(2)(ii).75.360(a) ........................................................................................................................................................... 75.360(a)(1).75.360(b) ........................................................................................................................................................... 75.360(b).75.360(b)(1) ....................................................................................................................................................... 75.360(b)(1).75.360(b)(3) ....................................................................................................................................................... 75.360(b)(3).75.360(b)(4) ....................................................................................................................................................... 75.350(b)(4).75.360(b)(6) ....................................................................................................................................................... 75.360(b)(6)(i).75.360(b)(6) ....................................................................................................................................................... 75.360(b)(6)(ii).75.360(c) ........................................................................................................................................................... 75.360(c).75.360(c)(1) ....................................................................................................................................................... 75.360(c)(1).75.360(c)(3 ........................................................................................................................................................ 75.360(c)(3).75.360(e) ........................................................................................................................................................... 75.363.75.360(f) ............................................................................................................................................................ 75.360(e).75.360(g) ........................................................................................................................................................... 75.360(f).75.360(h) ........................................................................................................................................................... 75.360(g).75.362(a)(1) ....................................................................................................................................................... 75.362(a)(1).75.363(a)(2) ....................................................................................................................................................... 75.363.75.362(c)(1) ....................................................................................................................................................... 75.362(c)(1).75.362(d)(1)(i) ................................................................................................................................................... 75.362(d)(1)(ii).75.362(d)(1)(ii) ................................................................................................................................................... 75.362(d)(1)(iii).75.362(d)(2) ....................................................................................................................................................... 75.362(d)(2).75.362(g) ........................................................................................................................................................... 75.363.75.362(h) ........................................................................................................................................................... 75.363.75.364(a)(1) ....................................................................................................................................................... 75.364(a)(1).75.364(a)(2)(i) ................................................................................................................................................... 75.364(a)(2)(i).75.364(a)(2)(ii) ................................................................................................................................................... 75.364(a)(2)(ii).75.364(a)(2)(iii) .................................................................................................................................................. 75.364(a)(2)(iii).75.364(h) ........................................................................................................................................................... 75.364(h).75.364(i) ............................................................................................................................................................ 75.364(i).75.370(a)(3) ....................................................................................................................................................... 75.370(a)(3).75.370(a)(3) ....................................................................................................................................................... 75.370(a)(3)(ii).75.370(a)(3) ....................................................................................................................................................... 75.370(a)(3)(iii).75.370(b)(1) ....................................................................................................................................................... 75.370(c)(1).75.370(b)(2) ....................................................................................................................................................... 75.370(c)(2).75.370(e) ........................................................................................................................................................... 75.370(f).75.370(e) ........................................................................................................................................................... 75.370(f)(2).75.370(e) ........................................................................................................................................................... 75.370(f)(3).75.371(r) ............................................................................................................................................................ 75.371(r).75.371(s) ........................................................................................................................................................... 75.371(s).75.371(z) ........................................................................................................................................................... 75.371(z).75.371(bb) ......................................................................................................................................................... 75.371(bb).75.371(cc) ......................................................................................................................................................... 75.371(cc).75.372(b)(3) ....................................................................................................................................................... 75.372(b)(3).75.380(d)(3) ....................................................................................................................................................... 75.380(d)(3).75.380(d)(4)(ii) ................................................................................................................................................... 75.380(d)(4)(ii).75.380(d)(5) ....................................................................................................................................................... 75.380(d)(5).75.380(f) ............................................................................................................................................................ 75.380(f).75.380(i)(2) ........................................................................................................................................................ 75.380(i)(2).75.383(a) ........................................................................................................................................................... 75.383(a).75.388(c) ........................................................................................................................................................... 75.388(c).75.389(c)(1) ....................................................................................................................................................... 75.389(c)(1).

III. Paperwork Reduction Act

The information collectionrequirements contained in this rule havebeen submitted to the Office ofManagement and Budget (OMB) forreview under the Paperwork ReductionAct of 1995 (44 U.S.C. 3501–3520), asimplemented by OMB in regulations at5 CFR part 1320. No person may berequired to respond to, or may besubjected to a penalty for failure tocomply with, these informationcollection requirements until they havebeen approved and MSHA hasannounced the assigned OMB controlnumber. The OMB control number,when assigned, will be announced by

separate notice in the Federal Register.In accordance with § 1320.11(h) of theimplementing regulations, OMB has 60days from today’s publication date inwhich to approve, disapprove, orinstruct MSHA to make a change to theinformation collection requirements inthis rule.

This final rule addresses commentssubmitted to OMB and MSHA on thecollection of information requirementsin the proposed rule. In revising therequirements from those that appearedin the proposed rule, MSHA hasevaluated the necessity and usefulnessof the collections of information;reevaluated MSHA’s estimate of theinformation collection burden,

including the validity of the underlyingmethodology and assumptions; andminimized the burden on respondentsfor the information collectionrequirements, to the extent possible.This final rule provides for the use ofelectronic storage and maintenance ofrecords.

Benefits

In assessing costs and benefits of theventilation rule, it is important to notethat ventilation of underground coalmines is the primary method ofpreventing the accumulation ofexplosive methane gas, controllingharmful respirable dust, and assuringthe quality of air miners breath. Because


of the potential for a large number offatalities resulting from ventilationproblems, MSHA has found it prudentto establish multiple safety factors andsafety work practices to better assureadequate protection for miners. It isextremely difficult to specificallyquantify safety benefits related to eachsafety factor. However, due to the close,confined nature of the workplace in anunderground coal mine, failure of anysafety factors or protective actionsrelated to ventilation can havedisastrous effects. The introduction ofthis rule lists some of those tragic mineaccidents. In the restricted workenvironment of an underground coalmine, failure of a single safety factor ornoncompliance with a safe workpractice could jeopardize the well-beingof all miners underground. The totaleffect of the provisions in this final rulein conjunction with MSHA’s existingventilation standards should decreasethe occurrence of fatalities, injuries,accidents, and illnesses in undergroundcoal mines.

With respect to this final rule, theAgency has identified nine fatalities andseven injuries which potentially couldhave been prevented by compliancewith these provisions. In addition, thefinal rule contains provisions to betterassure compliance with the respirabledust control parameters specified in themine ventilation plan. Adherence tothese parameters helps to maintain a

work environment free of excessivelevels of respirable dust, therebyimproving long-term health protectionfor miners and potentially reducing thenumber of miners afflicted with coalworkers’ pneumoconiosis.

Some provisions clarify the intent ofthe existing rule. Such clarificationsshould increase the likelihood ofcompliance and thereby will help toincrease the probability of preventing afatality, injury, or non-injury accident.For the provisions which offer analternative compliance option, theminers will be provided at least thesame level of safety provided by anexisting requirement. These provisionswill facilitate compliance by theoperator, thereby increasing thepotential for the rule to reduce theprobability of a ventilation-relatedexplosion or accident.

In conclusion, the Agency determinedthat these provisions will increase theprobability that compliance with theventilation rule will prevent futureventilation-related accidents andgenerate a safer mining environment.

Compliance Costs and Economic ImpactMSHA has compared the costs

associated with the existingrequirements with the costs of the newrequirements. Based upon the availabledata, MSHA estimates that compliancewith the rule will produce net total peryear costs of approximately $4.0 millionfor the mining industry. This $4.0

million is composed of approximately$0.6 million in net annualized costs(derived from $4.0 million one-timecosts) and approximately $3.4 millionnet annual recurring costs.

With respect to large undergroundcoal mines the net total per year costswill be approximately $3.0 million. This$3.0 million is composed ofapproximately $0.46 million in netannualized costs (derived from $3.0million one-time costs) andapproximately $2.54 million net annualrecurring costs.

With respect to small undergroundcoal mines the net total per year costswill be approximately $1.0 million. This$1.0 million is composed ofapproximately $0.14 million in netannualized costs (derived from $1.0million one-time costs) andapproximately $0.82 million net annualrecurring costs.

Executive Order 12866 requires thatregulatory agencies assess the impact tothe government for any regulationdetermined to be a significant regulatoryaction. MSHA does not believe that thisrule will create any significant costimpacts to the government. Theregulation can be implemented underexisting government practices withoutany substantial equipment or facilityexpenditures by the government.

The incremental compliance costs forall underground coal mines are listed byprovision in Table I.

TABLE IV–1.—COMPLIANCE COSTS TO COMPLY WITH THE VENTILATION RULE FOR ALL UNDERGROUND COAL MINES

[In thousands of dollars]

StandardFirstyearcosts

Annualizedcosts

Annualcosts

75.301 .................................................................................................................................................................... (100) (7) (20)75.310 .................................................................................................................................................................... 329 47 (70)75.311 .................................................................................................................................................................... ............ ................. ................75.312 .................................................................................................................................................................... ............ ................. (1,121)75.313 .................................................................................................................................................................... ............ ................. 32275.320 .................................................................................................................................................................... ............ ................. ................75.321 .................................................................................................................................................................... 250 35 4075.323 .................................................................................................................................................................... ............ ................. ................75.330 .................................................................................................................................................................... ............ ................. ................75.333 .................................................................................................................................................................... ............ ................. ................75.334 .................................................................................................................................................................... ............ ................. ................75.340 .................................................................................................................................................................... 63 975.342 .................................................................................................................................................................... 12 2 3875.344 .................................................................................................................................................................... 57 10 1,25675.360 .................................................................................................................................................................... 123 17 (1,556)75.362 .................................................................................................................................................................... 420 59 3,27575.363 .................................................................................................................................................................... ............ ................. 32175.364 .................................................................................................................................................................... ............ ................. 68275.370 .................................................................................................................................................................... ............ ................. 6775.371 .................................................................................................................................................................... ............ ................. 1375.372 .................................................................................................................................................................... ............ ................. ................75.380 .................................................................................................................................................................... 2,839 436 5175.382 .................................................................................................................................................................... ............ ................. 1375.388 .................................................................................................................................................................... ............ ................. 53


TABLE IV–1.—COMPLIANCE COSTS TO COMPLY WITH THE VENTILATION RULE FOR ALL UNDERGROUND COAL MINES—Continued


StandardFirstyearcosts

Annualizedcosts

Annualcosts

75.389.

Total costs ................................................................................................................................................... 3,993 608 3,364

Regulatory Flexibility Certification

The Regulatory Flexibility Actrequires that agencies evaluate andinclude, wherever possible, compliancealternatives that minimize any adverseimpact on small businesses whendeveloping regulatory standards. MSHAhas not exempted small mines from anyprovision of the rule and small mines

will benefit from some of the provisionsand the alternative compliancemethods.

MSHA determined that theserevisions will not generate a substantialcost increase for small mines. The lackof a substantial cost increase for smallmines, in conjunction with the fact thatsimilar hazards exist in both large andsmall mining operations, indicates that

regulatory relief is not warranted forsmall mining operations. Therefore,MSHA has determined that theseprovisions will not have a significantlyadverse impact upon a substantialnumber of small entities.

The incremental costs for small andlarge mines are listed by provision inTable II.

TABLE IV–2.—COMPLIANCE COSTS TO COMPLY WITH THE VENTILATION RULE FOR SMALL AND LARGE UNDERGROUNDCOAL MINES


StandardFirst year costs Annualized costs Annual costs

Small Large Small Large Small Large

75.301 ............................................................................... (100) (7) (20)75.310 ............................................................................... 273 56 39 8 (78) 875.311 ...............................................................................75.312 ............................................................................... (1,121)75.313 ............................................................................... 55 26775.320 ...............................................................................75.321 ............................................................................... 250 35 4075.323 ...............................................................................75.330 ...............................................................................75.333 ...............................................................................75.334 ...............................................................................75.340 ............................................................................... 4 59 1 875.342 ............................................................................... 6 6 1 1 18 2075.344 ............................................................................... 57 10 43 1,21375.360 ............................................................................... 37 86 5 12 100 (1,656)75.362 ............................................................................... 80 340 11 48 409 2,86675.363 ............................................................................... 98 22375.364 ............................................................................... 126 55675.370 ............................................................................... 12 5575.371 ............................................................................... 6 775.372 ...............................................................................75.380 ............................................................................... 585 2,254 89 347 6 4575.382 ............................................................................... 1375.388 ............................................................................... 25 2875.389 ...............................................................................

Total ....................................................................... 985 3,008 146 462 820 2,544

List of Subjects in 30 CFR Part 75

Escapeways, Mine safety and health,Underground coal mines, Ventilation.

Dated: March 4, 1996.J. Davitt McAteer,Assistant Secretary for Mine Safety andHealth.

Accordingly, part 75, subchapter O,chapter I, title 30 of the Code of FederalRegulations is amended as follows:

PART 75—MANDATORY SAFETYSTANDARDS—UNDERGROUND COALMINES

1. The authority citation for part 75 isrevised to read as follows:

Authority: 30 U.S.C. 811.

2. Subpart D of part 75 is revised toread as follows:


Subpart D—Ventilation

Sec.75.300 Scope.75.301 Definitions.75.302 Main mine fans.75.310 Installation of main mine fans.75.311 Main mine fan operation.75.312 Main mine fan examinations and

records.75.313 Main mine fan stoppage with

persons underground.75.320 Air quality detectors and

measurement devices.75.321 Air quality.75.322 Harmful quantities of noxious gases.75.323 Actions for excessive methane.75.324 Intentional changes in the

ventilation system.75.325 Air quantity.75.326 Mean entry air velocity.75.327 Air courses and trolley haulage

systems.75.330 Face ventilation control devices.75.331 Auxiliary fans and tubing.75.332 Working sections and working

places.75.333 Ventilation controls.75.334 Worked-out areas and areas where

pillars are being recovered.75.335 Construction of seals.75.340 Underground electrical installations.75.341 Direct-fired intake air heaters.75.342 Methane monitors.75.343 Underground shops.75.344 Compressors.75.350 Air courses and belt haulage entries.75.351 Atmospheric monitoring system

(AMS).75.352 Return air courses.75.360 Preshift examination.75.361 Supplemental examination.75.362 On-shift examination.75.363 Hazardous conditions; posting,

correcting and recording.75.364 Weekly examination.75.370 Mine ventilation plan; submission

and approval.75.371 Mine ventilation plan; contents.75.372 Mine ventilation map.75.373 Reopening mines.75.380 Escapeways; bituminous and lignite

mines.75.381 Escapeways; anthracite mines.75.382 Mechanical escape facilities.75.383 Escapeway maps and drills.75.384 Longwall and shortwall travelways.75.385 Opening new mines.75.386 Final mining of pillars.75.388 Boreholes in advance of mining.75.389 Mining into inaccessible areas.

§ 75.300 Scope.

This subpart sets requirements forunderground coal mine ventilation.

§ 75.301 Definitions.

In addition to the applicabledefinitions in § 75.2, the followingdefinitions apply in this subpart.

Air course. An entry or a set of entriesseparated from other entries bystoppings, overcasts, other ventilationcontrol devices, or by solid blocks ofcoal or rock so that any mixing of air

currents between each is limited toleakage.

Incombustible. Incapable of beingburned.

Intake air. Air that has not yetventilated the last working place on anysplit of any working section, or anyworked-out area, whether pillared ornonpillared.

Intrinsically safe. Incapable ofreleasing enough electrical or thermalenergy under normal or abnormalconditions to cause ignition of aflammable mixture of methane ornatural gas and air of the most easilyignitable composition.

Noncombustible Structure or Area.Describes a structure or area that willcontinue to provide protection againstflame spread for at least 1 hour whensubjected to a fire test incorporating anASTM E119–88 time/temperature heatinput, or equivalent.

Noncombustible Material. Describes amaterial which when used to constructa ventilation control results in a controlthat will continue to serve its intendedfunction for 1 hour when subjected to afire test incorporating an ASTM E119–88 time/temperature heat input, orequivalent.

Return air. Air that has ventilated thelast working place on any split of anyworking section or any worked-out areawhether pillared or nonpillared. If airmixes with air that has ventilated thelast working place on any split of anyworking section or any worked-out area,whether pillared or nonpillared, it isconsidered return air. For the purposesof § 75.507–1, air that has been used toventilate any working place in a coalproducing section or pillared area, or airthat has been used to ventilate anyworking face if such air is directed awayfrom the immediate return is return air.Notwithstanding the definition of intakeair, for the purpose of ventilation ofstructures, areas or installations that arerequired by this subpart D to beventilated to return air courses, and forventilation of seals, other air coursesmay be designated as return air coursesby the operator only when the air inthese air courses will not be used toventilate working places or otherlocations, structures, installations orareas required to be ventilated withintake air.

Worked-out area. An area wheremining has been completed, whetherpillared or nonpillared, excludingdeveloping entries, return air courses,and intake air courses.

§ 75.302 Main mine fans.Each coal mine shall be ventilated by

one or more main mine fans. Boosterfans shall not be installed underground

to assist main mine fans except inanthracite mines. In anthracite mines,booster fans installed in the main aircurrent or a split of the main air currentmay be used provided their use isapproved in the ventilation plan.

§ 75.310 Installation of main mine fans.

(a) Each main mine fan shall be—(1) Installed on the surface in an

incombustible housing;(2) Connected to the mine opening

with incombustible air ducts;(3) Equipped with an automatic

device that gives a signal at the minewhen the fan either slows or stops. Aresponsible person designated by theoperator shall always be at a surfacelocation at the mine where the signalcan be seen or heard while anyone isunderground. This person shall beprovided with two-way communicationwith the working sections and workstations where persons are routinelyassigned to work for the majority of ashift;

(4) Equipped with a pressurerecording device or system. Minespermitted to shut down main mine fansunder § 75.311 and which do not havea pressure recording device installed onmain mine fans shall have until March11, 1997 to install a pressure recordingdevice or system on all main mine fans.If a device or system other than acircular pressure recorder is used tomonitor main mine fan pressure, themonitoring device or system shallprovide a continuous graph orcontinuous chart of the pressure as afunction of time. At not more than 7-dayintervals, a hard copy of the continuousgraph or chart shall be generated or therecord of the fan pressure shall be storedelectronically. When records of fanpressure are stored electronically, thesystem used to store these records shallbe secure and not susceptible toalteration and shall be capable of storingthe required data. Records of the fanpressure shall be retained at a surfacelocation at the mine for at least 1 yearand be made available for inspection byauthorized representatives of theSecretary and the representative ofminers;

(5) Protected by one or more weakwalls or explosion doors, or acombination of weak walls andexplosion doors, located in direct linewith possible explosive forces;

(6) Except as provided underparagraph (e) of this section, offset by atleast 15 feet from the nearest side of themine opening unless an alternativemethod of protecting the fan and itsassociated components is approved inthe ventilation plan.


(b)(1) If an electric motor is used todrive a main mine fan, the motor shalloperate from a power circuitindependent of all mine power circuits.

(2) If an internal combustion engine isused to drive a main mine fan—

(i) The fuel supply shall be protectedagainst fires and explosions;

(ii) The engine shall be installed in anincombustible housing and be equippedwith a remote shut-down device;

(iii) The engine and the engineexhaust system shall be located out ofdirect line of the air current exhaustingfrom the mine; and

(iv) The engine exhaust shall bevented to the atmosphere so that theexhaust gases do not contaminate themine intake air current or anyenclosure.

(c) If a main mine fan monitoringsystem is used under § 75.312, thesystem shall—

(1) Record, as described in paragraph(a)(4) the mine ventilating pressure;

(2) Monitor bearing temperature,revolutions per minute, vibration,electric voltage, and amperage;

(3) Provide a printout of themonitored parameters, including themine ventilating pressure within areasonable period, not to exceed the endof the next scheduled shift duringwhich miners are underground; and

(4) Be equipped with an automaticdevice that signals when—

(i) An electrical or mechanicaldeficiency exists in the monitoringsystem; or

(ii) A sudden increase or loss in mineventilating pressure occurs.

(5) Provide monitoring, records,printouts, and signals required byparagraphs (c)(1) through (c)(4) at asurface location at the mine where aresponsible person designated by theoperator is always on duty and wheresignals from the monitoring system canbe seen or heard while anyone isunderground. This person shall beprovided with two-way communicationwith the working sections and workstations where persons are routinelyassigned to work for the majority of ashift.

(d) Weak walls and explosion doorsshall have cross-sectional areas at leastequal to that of the entry through whichthe pressure from an explosionunderground would be relieved. A weakwall and explosion door combinationshall have a total cross-sectional area atleast equal to that of the entry throughwhich the pressure from an explosionunderground would be relieved.

(e) If a mine fan is installed in linewith an entry, a slope, or a shaft—

(1) The cross-sectional area of thepressure relief entry shall be at leastequal to that of the fan entry;

(2) The fan entry shall be developedout of direct line with possibleexplosive forces;

(3) The coal or other solid materialbetween the pressure relief entry andthe fan entry shall be at least 2,500square feet; and

(4) The surface opening of thepressure relief entry shall be not lessthan 15 feet nor more than 100 feet fromthe surface opening of the fan entry andfrom the underground intersection ofthe fan entry and pressure relief entry.

(f) In mines ventilated by multiplemain mine fans, incombustible doorsshall be installed so that if any mainmine fan stops and air reversals throughthe fan are possible, the doors on theaffected fan automatically close.

§ 75.311 Main mine fan operation.(a) Main mine fans shall be

continuously operated, except asotherwise approved in the ventilationplan, or when intentionally stopped fortesting of automatic closing doors andautomatic fan signal devices,maintenance or adjustment of the fan, orto perform maintenance or repair workunderground that cannot otherwise bemade while the fan is operating.

(b) Except as provided in paragraph(c) of this section, when a main minefan is intentionally stopped and theventilating quantity provided by the fanis not maintained by a back-up fansystem—

(1) Only persons necessary to evaluatethe effect of the fan stoppage or restart,or to perform maintenance or repairwork that cannot otherwise be madewhile the fan is operating, shall bepermitted underground;

(2) Mechanized equipment shall beshut off before stopping the fan; and

(3) Electric power circuits enteringunderground areas of the mine shall bedeenergized.

(c) When a back-up fan system is usedthat does not provide the ventilatingquantity provided by the main mine fan,persons may be permitted in the mineand electric power circuits may beenergized as specified in the approvedventilation plan.

(d) If an unusual variance in the mineventilation pressure is observed, or if anelectrical or mechanical deficiency of amain mine fan is detected, the mineforeman or equivalent mine official, orin the absence of the mine foreman orequivalent mine official, a designatedcertified person acting for the mineforeman or equivalent mine officialshall be notified immediately, andappropriate action or repairs shall beinstituted promptly.

(e) While persons are underground, aresponsible person designated by the

operator shall always be at a surfacelocation where each main mine fansignal can be seen or heard.

(f) The area within 100 feet of mainmine fans and intake air openings shallbe kept free of combustible material,unless alternative precautions necessaryto provide protection from fire or otherproducts of combustion are approved inthe ventilation plan.

(g) If multiple mine fans are used, themine ventilation system shall bedesigned and maintained to eliminateareas without air movement.

(h) Any atmospheric monitoringsystem operated during fan stoppagesshall be intrinsically safe.

§ 75.312 Main mine fan examinations andrecords.

(a) To assure electrical andmechanical reliability of main minefans, each main mine fan and itsassociated components, includingdevices for measuring or recording mineventilation pressure, shall be examinedfor proper operation by a trained persondesignated by the operator.Examinations of main mine fans shall bemade at least once each day that the fanoperates, unless a fan monitoring systemis used. No examination is required onany day when no one, includingcertified persons, goes underground,except that an examination shall becompleted prior to anyone entering themine.

(b)(1) If a main mine fan monitoringsystem is used, a trained persondesignated by the operator shall—

(i) At least once each day review thedata provided by the fan monitoringsystem to assure that the fan and the fanmonitoring system are operatingproperly. No review is required on anyday when no one, including certifiedpersons, goes underground, except thata review of the data shall be performedprior to anyone entering theunderground portion of the mine. Datareviewed should include the fanpressure, bearing temperature,revolutions per minute, vibration,electric voltage, and amperage; and

(ii) At least every 7 days—(A) Test the monitoring system for

proper operation; and(B) Examine each main mine fan and

its associated components to assureelectrical and mechanical reliability ofmain mine fans.

(2) If the monitoring systemmalfunctions, the malfunction shall becorrected, or paragraph (a) of thissection shall apply.

(c) At least every 31 days, theautomatic fan signal device for eachmain mine fan shall be tested bystopping the fan. Only persons


necessary to evaluate the effect of thefan stoppage or restart, or to performmaintenance or repair work that cannototherwise be made while the fan isoperating, shall be permittedunderground. Notwithstanding therequirement of § 75.311(b)(3),underground power may remainenergized during this test provided noone, including persons identified in§ 75.311(b)(1), is underground. If the fanis not restarted within 15 minutes,underground power shall bedeenergized and no one shall enter anyunderground area of the mine until thefan is restarted and an examination ofthe mine is conducted as described in§ 75.360 (b) through (e) and the minehas been determined to be safe.

(d) At least every 31 days, theautomatic closing doors in multiplemain mine fan systems shall be testedby stopping the fan. Only personsnecessary to evaluate the effect of thefan stoppage or restart, or to performmaintenance or repair work that cannototherwise be made while the fan isoperating, shall be permittedunderground. Notwithstanding theprovisions of § 75.311, undergroundpower may remain energized during thistest provided no one, including personsidentified in § 75.311(b)(1), isunderground. If the fan is not restartedwithin 15 minutes, underground powershall be deenergized and no one shallenter any underground area of the mine,until the fan is restarted and anexamination of the mine is conducted asdescribed in § 75.360 (b) through (e) andthe mine has been determined to besafe.

(e) Circular main mine fan pressurerecording charts shall be changed beforethe beginning of a second revolution.

(f)(1) Certification. Persons makingmain mine fan examinations shallcertify by initials and date at the fan oranother location specified by theoperator that the examinations weremade. Each certification shall identifythe main mine fan examined.

(2) Persons reviewing data producedby a main mine fan monitoring systemshall certify by initials and date on aprinted copy of the data from the systemthat the review was completed. In lieuof certification on a copy of the data, theperson reviewing the data may certifyelectronically that the review wascompleted. Electronic certification shallbe by handwritten initials and date in acomputer system so as to be secure andnot susceptible to alteration.

(g)(1) Recordkeeping. By the end ofthe shift on which the examination ismade, persons making main mine fanexaminations shall record alluncorrected defects that may affect the

operation of the fan that are notcorrected by the end of that shift.Records shall be maintained in a securebook that is not susceptible to alterationor electronically in a computer systemso as to be secure and not susceptibleto alteration.

(2) When a fan monitoring system isused in lieu of the daily fanexamination—

(i) The certified copies of dataproduced by fan monitoring systemsshall be maintained separate from othercomputer-generated reports or data; and

(ii) A record shall be made of any fanmonitoring system malfunctions,electrical or mechanical deficiencies inthe monitoring system and any suddenincrease or loss in mine ventilatingpressure. The record shall be made bythe end of the shift on which the reviewof the data is completed and shall bemaintained in a secure book that is notsusceptible to alteration orelectronically in a computer system soas to be secure and not susceptible toalteration.

(3) By the end of the shift on whichthe monthly test of the automatic fansignal device or the automatic closingdoors is completed, persons makingthese tests shall record the results of thetests. Records shall be maintained in asecure book that is not susceptible toalteration or electronically in acomputer system so as to be secure andnot susceptible to alteration.

(h) Retention period. Records,including records of mine fan pressureand the certified copies of dataproduced by fan monitoring systems,shall be retained at a surface location atthe mine for at least 1 year and shall bemade available for inspection byauthorized representatives of theSecretary and the representative ofminers.

§ 75.313 Main mine fan stoppage withpersons underground.

(a) If a main mine fan stops whileanyone is underground and theventilating quantity provided by the fanis not maintained by a back-up fansystem—

(1) Electrically powered equipment ineach working section shall bedeenergized;

(2) Other mechanized equipment ineach working section shall be shut off;and

(3) Everyone shall be withdrawn fromthe working sections and areas wheremechanized mining equipment is beinginstalled or removed.

(b) If ventilation is restored within 15minutes after a main mine fan stops,certified persons shall examine formethane in the working places and in

other areas where methane is likely toaccumulate before work is resumed andbefore equipment is energized orrestarted in these areas.

(c) If ventilation is not restored within15 minutes after a main mine fanstops—

(1) Everyone shall be withdrawn fromthe mine;

(2) Underground electric powercircuits shall be deenergized. However,circuits necessary to withdraw personsfrom the mine need not be deenergizedif located in areas or haulageways wheremethane is not likely to migrate to oraccumulate. These circuits shall bedeenergized as persons are withdrawn;and

(3) Mechanized equipment notlocated on working sections shall beshut off. However, mechanizedequipment necessary to withdrawpersons from the mine need not be shutoff if located in areas where methane isnot likely to migrate to or accumulate.

(d)(1) When ventilation is restored—(i) No one other than designated

certified examiners shall enter anyunderground area of the mine until anexamination is conducted as describedin § 75.360(b) through (e) and the areahas been determined to be safe.Designated certified examiners shallenter the underground area of the minefrom which miners have beenwithdrawn only after the fan hasoperated for at least 15 minutes unlessa longer period of time is specified inthe approved ventilation plan.

(ii) Underground power circuits shallnot be energized and nonpermissiblemechanized equipment shall not bestarted or operated in an area until anexamination is conducted as describedin § 75.360(b) through (e) and the areahas been determined to be safe, exceptthat designated certified examiners mayuse nonpermissible transportationequipment in intake airways to facilitatethe making of the required examination.

(2) If ventilation is restored to themine before miners reach the surface,the miners may return to undergroundworking areas only after an examinationof the areas is made by a certifiedperson and the areas are determined tobe safe.

(e) Any atmospheric monitoringsystem operated during fan stoppagesshall be intrinsically safe.

§ 75.320 Air quality detectors andmeasurement devices.

(a) Tests for methane shall be made bya qualified person with MSHA approveddetectors that are maintained inpermissible and proper operatingcondition and calibrated with a known


methane-air mixture at least once every31 days.

(b) Tests for oxygen deficiency shallbe made by a qualified person withMSHA approved oxygen detectors thatare maintained in permissible andproper operating condition and that candetect 19.5 percent oxygen with anaccuracy of ±0.5 percent. The oxygendetectors shall be calibrated at the startof each shift that the detectors will beused.

(c) Handheld devices that containelectrical components and that are usedfor measuring air velocity, carbonmonoxide, oxides of nitrogen, and othergases shall be approved and maintainedin permissible and proper operatingcondition.

(d) An oxygen detector approved byMSHA shall be used to make tests foroxygen deficiency required by theregulations in this part. Permissibleflame safety lamps may only be used asa supplementary testing device.

(e) Maintenance of instrumentsrequired by paragraphs (a) through (d) ofthis section shall be done by personstrained in such maintenance.

§ 75.321 Air quality.(a)(1) The air in areas where persons

work or travel, except as specified inparagraph (a)(2) of this section, shallcontain at least 19.5 percent oxygen andnot more than 0.5 percent carbondioxide, and the volume and velocity ofthe air current in these areas shall besufficient to dilute, render harmless,and carry away flammable, explosive,noxious, and harmful gases, dusts,smoke, and fumes.

(2) The air in areas of bleeder entriesand worked-out areas where personswork or travel shall contain at least 19.5percent oxygen, and carbon dioxidelevels shall not exceed 0.5 percent timeweighted average and 3.0 percent shortterm exposure limit.

(b) Notwithstanding the provisions of§ 75.322, for the purpose of preventingexplosions from gases other thanmethane, the following gases shall notbe permitted to accumulate in excess ofthe concentrations listed below:

(1) Carbon monoxide (CO)—2.5percent

(2) Hydrogen (H2)—.80 percent(3) Hydrogen sulfide (H2S)—.80

percent(4) Acetylene (C2H2)—.40 percent(5) Propane (C3H8)—.40 percent(6) MAPP (methyl-acetylene-

propylene-propodiene)—.30 percent

§ 75.322 Harmful quantities of noxiousgases.

Concentrations of noxious orpoisonous gases, other than carbon

dioxide, shall not exceed the currentthreshold limit values (TLV) asspecified and applied by the ACGIH.Detectors or laboratory analysis of mineair samples shall be used to determinethe concentrations of harmful, noxious,or poisonous gases.

§ 75.323 Actions for excessive methane.

(a) Location of tests. Tests for methaneconcentrations under this section shallbe made at least 12 inches from the roof,face, ribs, and floor.

(b) Working places and intake aircourses.

(1) When 1.0 percent or more methaneis present in a working place or anintake air course, including an aircourse in which a belt conveyor islocated, or in an area where mechanizedmining equipment is being installed orremoved—

(i) Except intrinsically safeatmospheric monitoring systems (AMS),electrically powered equipment in theaffected area shall be deenergized, andother mechanized equipment shall beshut off;

(ii) Changes or adjustments shall bemade at once to the ventilation systemto reduce the concentration of methaneto less than 1.0 percent; and

(iii) No other work shall be permittedin the affected area until the methaneconcentration is less than 1.0 percent.

(2) When 1.5 percent or more methaneis present in a working place or anintake air course, including an aircourse in which a belt conveyor islocated, or in an area where mechanizedmining equipment is being installed orremoved—

(i) Everyone except those personsreferred to in § 104(c) of the Act shall bewithdrawn from the affected area; and

(ii) Except for intrinsically safe AMS,electrically powered equipment in theaffected area shall be disconnected atthe power source.

(c) Return air split. (1) When 1.0percent or more methane is present ina return air split between the lastworking place on a working section andwhere that split of air meets anothersplit of air, or the location at which thesplit is used to ventilate seals orworked-out areas changes oradjustments shall be made at once to theventilation system to reduce theconcentration of methane in the returnair to less than 1.0 percent.

(2) When 1.5 percent or more methaneis present in a return air split betweenthe last working place on a workingsection and where that split of air meetsanother split of air, or the locationwhere the split is used to ventilate sealsor worked-out areas—

(i) Everyone except those personsreferred to in § 104(c) of the Act shall bewithdrawn from the affected area;

(ii) Other than intrinsically safe AMS,equipment in the affected area shall bedeenergized, electric power shall bedisconnected at the power source, andother mechanized equipment shall beshut off; and

(iii) No other work shall be permittedin the affected area until the methaneconcentration in the return air is lessthan 1.0 percent.

(d) Return air split alternative. (1) Theprovisions of this paragraph apply if—

(i) The quantity of air in the splitventilating the active workings is atleast 27,000 cubic feet per minute in thelast open crosscut or the quantityspecified in the approved ventilationplan, whichever is greater;

(ii) The methane content of the air inthe split is continuously monitoredduring mining operations by an AMSthat gives a visual and audible signal onthe working section when the methanein the return air reaches 1.5 percent, andthe methane content is monitored asspecified in § 75.351; and

(iii) Rock dust is continuously appliedwith a mechanical duster to the returnair course during coal production at alocation in the air course immediatelyoutby the most inby monitoring point.

(2) When 1.5 percent or more methaneis present in a return air split betweena point in the return opposite thesection loading point and where thatsplit of air meets another split of air orwhere the split of air is used to ventilateseals or worked-out areas—

(i) Changes or adjustments shall bemade at once to the ventilation systemto reduce the concentration of methanein the return air below 1.5 percent;

(ii) Everyone except those personsreferred to in § 104(c) of the Act shall bewithdrawn from the affected area;

(iii) Except for intrinsically safe AMS,equipment in the affected area shall bedeenergized, electric power shall bedisconnected at the power source, andother mechanized equipment shall beshut off; and

(iv) No other work shall be permittedin the affected area until the methaneconcentration in the return air is lessthan 1.5 percent.

(e) Bleeders and other return aircourses. The concentration of methanein a bleeder split of air immediatelybefore the air in the split joins anothersplit of air, or in a return air courseother than as described in paragraphs (c)and (d) of this section, shall not exceed2.0 percent.


§ 75.324 Intentional changes in theventilation system.

(a) A person designated by theoperator shall supervise any intentionalchange in ventilation that—

(1) Alters the main air current or anysplit of the main air current in a mannerthat could materially affect the safety orhealth of persons in the mine; or

(2) Affects section ventilation by9,000 cubic feet per minute of air ormore in bituminous or lignite mines, or5,000 cubic feet per minute of air ormore in anthracite mines.

(b) Intentional changes shall be madeonly under the following conditions:

(1) Electric power shall be removedfrom areas affected by the ventilationchange and mechanized equipment inthose areas shall be shut off before theventilation change begins.

(2) Only persons making the changein ventilation shall be in the mine.

(3) Electric power shall not berestored to the areas affected by theventilation change and mechanizedequipment shall not be restarted until acertified person has examined theseareas for methane accumulation and foroxygen deficiency and has determinedthat the areas are safe.

§ 75.325 Air quantity.(a)(1) In bituminous and lignite mines

the quantity of air shall be at least 3,000cubic feet per minute reaching eachworking face where coal is being cut,mined, drilled for blasting, or loaded.When a greater quantity is necessary todilute, render harmless, and carry awayflammable, explosive, noxious, andharmful gases, dusts, smoke, and fumes,this quantity shall be specified in theapproved ventilation plan. A minimumair quantity may be required to bespecified in the approved ventilationplan for other working places orworking faces.

(2) The quantity of air reaching theworking face shall be determined at ornear the face end of the line curtain,ventilation tubing, or other ventilationcontrol device. If the curtain, tubing, ordevice extends beyond the last row ofpermanent roof supports, the quantity ofair reaching the working face shall bedetermined behind the line curtain or inthe ventilation tubing at or near the lastrow of permanent supports.

(3) If machine mounted dustcollectors or diffuser fans are used, theapproved ventilation plan shall specifythe operating volume of the dustcollector or diffuser fan.

(b) In bituminous and lignite mines,the quantity of air reaching the last opencrosscut of each set of entries or roomson each working section and thequantity of air reaching the intake end

of a pillar line shall be at least 9,000cubic feet per minute unless a greaterquantity is required to be specified inthe approved ventilation plan.

(c) In longwall and shortwall miningsystems—

(1) The quantity of air shall be at least30,000 cubic feet per minute reachingthe working face of each longwall,unless the operator demonstrates that alesser air quantity will maintaincontinual compliance with applicablemethane and respirable dust standards.This lesser quantity shall be specified inthe approved ventilation plan. Aquantity greater than 30,000 cubic feetper minute may be required to bespecified in the approved ventilationplan.

(2) The velocity of air that will beprovided to control methane andrespirable dust below applicablestandards on each longwall or shortwalland the locations where these velocitieswill be provided shall be specified inthe approved ventilation plan. Thelocations specified shall be at least 50feet but no more than 100 feet from theheadgate and tailgate, respectively.

(d) Ventilation shall be maintainedduring installation and removal ofmechanized mining equipment. Theapproved ventilation plan shall specifythe minimum quantity of air, thelocations where this quantity will beprovided and the ventilation controlsrequired.

(e) In anthracite mines, the quantity ofair shall be as follows:

(1) At least 1,500 cubic feet perminute reaching each working facewhere coal is being mined, unless agreater quantity is required to bespecified in the approved ventilationplan.

(2) At least 5,000 cubic feet perminute passing through the last opencrosscut in each set of entries or roomsand at the intake end of any pillar line,unless a greater quantity is required tobe specified in the approved ventilationplan.

(3) When robbing areas where aircurrents cannot be controlled and airmeasurements cannot be obtained, theair shall have perceptible movement.

§ 75.326 Mean entry air velocity.In exhausting face ventilation

systems, the mean entry air velocityshall be at least 60 feet per minutereaching each working face where coalis being cut, mined, drilled for blasting,or loaded, and to any other workingplaces as required in the approvedventilation plan. A lower mean entry airvelocity may be approved in theventilation plan if the lower velocitywill maintain methane and respirable

dust concentrations below theapplicable levels. Mean entry airvelocity shall be determined at or nearthe inby end of the line curtain,ventilation tubing, or other faceventilation control devices.

§ 75.327 Air courses and trolley haulagesystems.

(a) In any mine opened on or afterMarch 30, 1970, or in any new workingsection of a mine opened before thatdate, where trolley haulage systems aremaintained and where trolley wires ortrolley feeder wires are installed, anauthorized representative of theSecretary shall require enough entries orrooms as intake air courses to limit thevelocity of air currents in thehaulageways to minimize the hazards offires and dust explosions in thehaulageways.

(b) Unless the district managerapproves a higher velocity, the velocityof the air current in the trolley haulageentries shall be limited to not more than250 feet per minute. A higher airvelocity may be required to limit themethane content in these haulageentries or elsewhere in the mine to lessthan 1.0 percent and provide anadequate supply of oxygen.

§ 75.330 Face ventilation control devices.

(a) Brattice cloth, ventilation tubingand other face ventilation controldevices shall be made of flame-resistantmaterial approved by MSHA.

(b)(1) Ventilation control devices shallbe used to provide ventilation to dilute,render harmless, and to carry awayflammable, explosive, noxious, andharmful gases, dusts, smoke, andfumes—

(i) To each working face from whichcoal is being cut, mined, drilled forblasting, or loaded; and

(ii) To any other working places asrequired by the approved ventilationplan.

(2) These devices shall be installed ata distance no greater than 10 feet fromthe area of deepest penetration to whichany portion of the face has beenadvanced unless an alternative distanceis specified and approved in theventilation plan. Alternative distancesspecified shall be capable ofmaintaining concentrations of respirabledust, methane, and other harmful gasesbelow the levels specified in theapplicable sections of this chapter.

(c) When the line brattice or any otherface ventilation control device isdamaged to an extent that ventilation ofthe working face is inadequate,production activities in the workingplace shall cease until necessary repairs


are made and adequate ventilation isrestored.

§ 75.331 Auxiliary fans and tubing.(a) When auxiliary fans and tubing are

used for face ventilation, each auxiliaryfan shall be—

(1) Permissible, if the fan iselectrically operated;

(2) Maintained in proper operatingcondition;

(3) Deenergized or shut off when noone is present on the working section;and

(4) Located and operated to avoidrecirculation of air.

(b) If a deficiency exists in anyauxiliary fan system, the deficiencyshall be corrected or the auxiliary fanshall be deenergized immediately.

(c) If the air passing through anauxiliary fan or tubing contains 1.0percent or more methane, power toelectrical equipment in the workingplace and to the auxiliary fan shall bedeenergized, and other mechanizedequipment in the working place shall beshut off until the methane concentrationis reduced to less than 1.0 percent.

(d) When an auxiliary fan isstopped—

(1) Line brattice or other faceventilation control devices shall be usedto maintain ventilation to affected faces;and

(2) Electrical equipment in theaffected working places shall bedisconnected at the power source, andother mechanized equipment shall beshut off until ventilation to the workingplace is restored.

§ 75.332 Working sections and workingplaces.

(a)(1) Each working section and eacharea where mechanized miningequipment is being installed orremoved, shall be ventilated by aseparate split of intake air directed byovercasts, undercasts or otherpermanent ventilation controls.

(2) When two or more sets of miningequipment are simultaneously engagedin cutting, mining, or loading coal orrock from working places within thesame working section, each set ofmining equipment shall be on a separatesplit of intake air.

(3) For purposes of this section, a setof mining equipment includes a singleloading machine, a single continuousmining machine, or a single longwall orshortwall mining machine.

(b)(1) Air that has passed through anyarea that is not examined under§§ 75.360, 75.361 or 75.364 of thissubpart, or through an area wheresecond mining has been done shall notbe used to ventilate any working place.

Second mining is intentional retreatmining where pillars have been whollyor partially removed, regardless of theamount of recovery obtained.

(2) Air that has passed by any openingof any unsealed area that is notexamined under §§ 75.360, 75.361 or75.364 of this subpart, shall not be usedto ventilate any working place.

§ 75.333 Ventilation controls.(a) For purposes of this section,

‘‘doors’’ include any door frames.(b) Permanent stoppings or other

permanent ventilation control devicesconstructed after November 15, 1992,shall be built and maintained—

(1) Between intake and return aircourses, except temporary controls maybe used in rooms that are 600 feet or lessfrom the centerline of the entry fromwhich the room was developedincluding where continuous facehaulage systems are used in such rooms.Unless otherwise approved in theventilation plan, these stoppings orcontrols shall be maintained to andincluding the third connecting crosscutoutby the working face;

(2) To separate belt conveyorhaulageways from return air courses,except where belt entries in areas ofmines developed before March 30, 1970,are used as return air courses;

(3) To separate belt conveyorhaulageways from intake air courseswhen the air in the intake air courses isused to provide air to active workingplaces. Temporary ventilation controlsmay be used in rooms that are 600 feetor less from the centerline of the entryfrom which the rooms were developedincluding where continuous facehaulage systems are used in such rooms.When continuous face haulage systemsare used, permanent stoppings or otherpermanent ventilation control devicesshall be built and maintained to theoutby most point of travel of the dollyor 600 feet from the point of deepestpenetration in the conveyor belt entry,whichever distance is closer to the pointof deepest penetration, to separate thecontinuous haulage entry from theintake entries;

(4) To separate the primary escapewayfrom belt and trolley haulage entries, asrequired by § 75.380(g). For thepurposes of § 75.380(g), the loadingpoint for a continuous haulage systemshall be the outby most point of travelof the dolly or 600 feet from the pointof deepest penetration, whicheverdistance is less; and

(5) In return air courses to direct airinto adjacent worked-out areas.

(c) Personnel doors shall beconstructed of noncombustible materialand shall be of sufficient strength to

serve their intended purpose ofmaintaining separation and permittingtravel between air courses, and shall beinstalled as follows in permanentstoppings constructed after November15, 1992:

(1) The distance between personneldoors shall be no more than 300 feet inseam heights below 48 inches and 600feet in seam heights 48 inches or higher.

(2) The location of all personnel doorsin stoppings along escapeways shall beclearly marked so that the doors may beeasily identified by anyone traveling inthe escapeway and in the entries oneither side of the doors.

(3) When not in use, personnel doorsshall be closed.

(d) Doors, other than personnel doors,constructed after November 15, 1992,that are used in lieu of permanentstoppings or to control ventilationwithin an air course shall be:

(1) Made of noncombustible materialor coated on all accessible surfaces withflame-retardant material having a flame-spread index of 25 or less, as testedunder ASTM E162–87.

(2) Of sufficient strength to serve theirintended purpose of maintainingseparation and permitting travelbetween or within air courses or entries.

(3) Installed in pairs to form anairlock. When an airlock is used, oneside of the airlock shall remain closed.When not in use, both sides shall beclosed.

(e)(1)(i) Except as provided inparagraphs (e)(2), (e)(3) and (e)(4) of thissection all overcasts, undercasts, shaftpartitions, permanent stoppings, andregulators, installed after March 11,1997, shall be constructed in atraditionally accepted method and ofmaterials that have been demonstratedto perform adequately or in a methodand of materials that have been testedand shown to have a minimum strengthequal to or greater than the traditionallyaccepted in-mine controls. Tests may beperformed under ASTM E72–80 Section12—Transverse Load-SpecimenVertical, load only, or the operator mayconduct comparative in-mine tests. In-mine tests shall be designed todemonstrate the comparative strength ofthe proposed construction and atraditionally accepted in-mine control.

(ii) All overcasts, undercasts, shaftpartitions, permanent stoppings, andregulators, installed after November 15,1992, shall be constructed ofnoncombustible material. Materials thatare suitable for the construction ofovercasts, undercasts, shaft partitions,permanent stoppings, and regulatorsinclude concrete, concrete block, brick,cinder block, tile, or steel. Noventilation controls installed after


November 15, 1992, shall be constructedof aluminum.

(2) In anthracite mines, permanentstoppings may be constructed ofoverlapping layers of hardwood mineboards, if the stoppings are a minimum2 inches thick.

(3) When timbers are used to createpermanent stoppings in heaving orcaving areas, the stoppings shall becoated on all accessible surfaces with aflame-retardant material having a flame-spread index of 25 or less, as testedunder ASTM E162–87, ‘‘SurfaceFlammability of Materials Using aRadiant Heat Energy Source.’’

(4) In anthracite mines, doors andregulators may be constructed ofoverlapping layers of hardwood boards,if the doors, door frames, and regulatorsare a minimum 2 inches thick.

(f) When sealants are applied toventilation controls, the sealant shallhave a flame-spread index of 25 or lessunder ASTM E162–87.

(g) Before mining is discontinued inan entry or room that is advanced morethan 20 feet from the inby rib, a crosscutshall be made or line brattice shall beinstalled and maintained to provideadequate ventilation. When conditionssuch as methane liberation warrant adistance less than 20 feet, the approvedventilation plan shall specify thelocation of such rooms or entries andthe maximum distance they will bedeveloped before a crosscut is made orline brattice is installed.

(h) All permanent ventilationcontrols, including seals, shall bemaintained to serve the purpose forwhich they were built.

§ 75.334 Worked-out areas and areaswhere pillars are being recovered.

(a) Worked-out areas where no pillarshave been recovered shall be—

(1) Ventilated so that methane-airmixtures and other gases, dusts, andfumes from throughout the worked-outareas are continuously diluted androuted into a return air course or to thesurface of the mine; or

(2) Sealed.(b)(1) During pillar recovery a bleeder

system shall be used to control the airpassing through the area and tocontinuously dilute and move methane-air mixtures and other gases, dusts, andfumes from the worked-out area awayfrom active workings and into a returnair course or to the surface of the mine.

(2) After pillar recovery a bleedersystem shall be maintained to provideventilation to the worked-out area, orthe area shall be sealed.

(c) The approved ventilation planshall specify the following:

(1) The design and use of bleedersystems;

(2) The means to determine theeffectiveness of bleeder systems;

(3) The means for adequatelymaintaining bleeder entries free ofobstructions such as roof falls andstanding water; and

(4) The location of ventilating devicessuch as regulators, stoppings andbleeder connectors used to control airmovement through the worked-out area.

(d) If the bleeder system used does notcontinuously dilute and move methane-air mixtures and other gases, dusts, andfumes away from worked-out areas intoa return air course or to the surface ofthe mine, or it cannot be determined byexaminations or evaluations under§ 75.364 that the bleeder system isworking effectively, the worked-out areashall be sealed.

(e) Each mining system shall bedesigned so that each worked-out areacan be sealed. The approved ventilationplan shall specify the location and thesequence of construction of proposedseals.

(f) In place of the requirements ofparagraphs (a) and (b) of this section, formines with a demonstrated history ofspontaneous combustion, or that arelocated in a coal seam determined to besusceptible to spontaneous combustion,the approved ventilation plan shallspecify the following:

(1) Measures to detect methane,carbon monoxide, and oxygenconcentrations during and after pillarrecovery, and in worked-out areaswhere no pillars have been recovered, todetermine if the areas must beventilated or sealed.

(2) Actions that will be taken toprotect miners from the hazards ofspontaneous combustion.

(3) If a bleeder system will not beused, the methods that will be used tocontrol spontaneous combustion,accumulations of methane-air mixtures,and other gases, dusts, and fumes in theworked-out area.

§ 75.335 Construction of seals.(a)(1) Each seal constructed after

November 15, 1992, shall be—(i) Constructed of solid concrete

blocks at least 6 by 8 by 16 inches, laidin a transverse pattern with mortarbetween all joints;

(ii) Hitched into solid ribs to a depthof at least 4 inches and hitched at least4 inches into the floor;

(iii) At least 16 inches thick. Whenthe thickness of the seal is less than 24inches and the width is greater than 16feet or the height is greater than 10 feet,a pilaster shall be interlocked near thecenter of the seal. The pilaster shall beat least 16 inches by 32 inches; and

(iv) Coated on all accessible surfaceswith flame-retardant material that will

minimize leakage and that has a flame-spread index of 25 or less, as testedunder ASTM E162–87, ‘‘SurfaceFlammability of Materials Using aRadiant Heat Energy Source.’’

(2) Alternative methods or materialsmay be used to create a seal if they canwithstand a static horizontal pressure of20 pounds per square inch provided themethod of installation and the materialused approved in the ventilation plan.If the alternative methods or materialsinclude the use of timbers, the timbersalso shall be coated on all accessiblesurfaces with flame-retardant materialhaving a flame-spread index 25 or less,as tested under ASTM E162–87.

(b) A sampling pipe or pipes shall beinstalled in each set of seals for aworked-out area. Each pipe shall—

(1) Extend into the sealed area asufficient distance (at least 15 feet) toobtain a representative sample frombehind the seal;

(2) Be equipped with a cap or shut-offvalve; and

(3) Be installed with the sampling endof the pipe about 12 inches from theroof.

(c)(1) A corrosion-resistant water pipeor pipes shall be installed in seals at thelow points of the area being sealed andat all other locations necessary whenwater accumulation within the sealedarea is possible; and

(2) Each water pipe shall have a watertrap installed on the outby side of theseal.

§ 75.340 Underground electricalinstallations.

(a) Underground transformer stations,battery charging stations, substations,rectifiers, and water pumps shall behoused in noncombustible structures orareas or be equipped with a firesuppression system meeting therequirements of § 75.1107–3 through§ 75.1107–16.

(1) When a noncombustible structureor area is used, these installations shallbe—

(i) Ventilated with intake air that iscoursed into a return air course or to thesurface and that is not used to ventilateworking places; or

(ii) Ventilated with intake air that ismonitored for carbon monoxide orsmoke by an AMS installed andoperated according to § 75.351.Monitoring of intake air ventilatingbattery charging stations shall be donewith sensors not affected by hydrogen;or

(iii) Ventilated with intake air andequipped with sensors to monitor forheat and for carbon monoxide or smoke.Monitoring of intake air ventilatingbattery charging stations shall be done


with sensors not affected by hydrogen.The sensors shall deenergize power tothe installation, activate a visual andaudible alarm located outside of and onthe intake side of the enclosure, andactivate doors that will automaticallyclose when either of the followingoccurs:

(A) The temperature in thenoncombustible structure reaches 165°F; or

(B) The carbon monoxideconcentration reaches 10 parts permillion above the ambient level for thearea, or the optical density of smokereaches 0.022 per meter. At least every31 days, sensors installed to monitor forcarbon monoxide shall be calibratedwith a known concentration of carbonmonoxide and air sufficient to activatethe closing door, or each smoke sensorshall be tested to determine that itfunctions correctly.

(2) When a fire suppression system isused, these installations shall be—

(i) Ventilated with intake air that iscoursed into a return air course or to thesurface and that is not used to ventilateworking places; or

(ii) Ventilated with intake air that ismonitored for carbon monoxide orsmoke by an AMS installed andoperated according to § 75.351.Monitoring of intake air ventilatingbattery charging stations shall be donewith sensors not affected by hydrogen.

(b) This section does not apply to—(1) Rectifiers and power centers with

transformers that are either dry-type orcontain nonflammable liquid, if they arelocated at or near the section and aremoved as the working section advancesor retreats;

(2) Submersible pumps;(3) Permissible pumps and associated

permissible switchgear;(4) Pumps located on or near the

section and that are moved as theworking section advances or retreats;

(5) Pumps installed in anthracitemines; and

(6) Small portable pumps.

§ 75.341 Direct-fired intake air heaters.(a) If any system used to heat intake

air malfunctions, the heaters affectedshall switch off automatically.

(b) Thermal overload devices shallprotect the blower motor fromoverheating.

(c) The fuel supply shall turn offautomatically if a flame-out occurs.

(d) Each heater shall be located orguarded to prevent contact by personsand shall be equipped with a screen atthe inlet to prevent combustiblematerials from passing over the burnerunits.

(e) If intake air heaters use liquefiedfuel systems—

(1) Hydrostatic relief valves installedon vaporizers and on storage tanks shallbe vented; and

(2) Fuel storage tanks shall be locatedor protected to prevent fuel from leakinginto the mine.

(f) Following any period of 8 hours ormore during which a heater does notoperate, the heater and its associatedcomponents shall be examined withinits first hour of operation. Additionally,each heater and its components shall beexamined at least once each shift thatthe heater operates. The examinationshall include measurement of thecarbon monoxide concentration at thebottom of each shaft, slope, or in thedrift opening where air is being heated.The measurements shall be taken by aperson designated by the operator or bya carbon monoxide sensor that iscalibrated with a known concentrationof carbon monoxide and air at least onceevery 31 days. When the carbonmonoxide concentration at this locationreaches 50 parts per million, the heatercausing the elevated carbon monoxidelevel shall be shut down.

§ 75.342 Methane monitors.(a)(1) MSHA approved methane

monitors shall be installed on all facecutting machines, continuous miners,longwall face equipment, loadingmachines, and other mechanizedequipment used to extract or load coalwithin the working place.

(2) The sensing device for methanemonitors on longwall shearing machinesshall be installed at the return air endof the longwall face. An additionalsensing device also shall be installed onthe longwall shearing machine,downwind and as close to the cuttinghead as practicable. An alternativelocation or locations for the sensingdevice required on the longwallshearing machine may be approved inthe ventilation plan.

(3) The sensing devices of methanemonitors shall be installed as close tothe working face as practicable.

(4) Methane monitors shall bemaintained in permissible and properoperating condition and shall becalibrated with a known air-methanemixture at least once every 31 days. Toassure that methane monitors areproperly maintained and calibrated, theoperator shall:

(i) Use persons properly trained in themaintenance, calibration, andpermissibility of methane monitors tocalibrate and maintain the devices.

(ii) Maintain a record of all calibrationtests of methane monitors. Records shallbe maintained in a secure book that isnot susceptible to alteration orelectronically in a computer system so

as to be secure and not susceptible toalteration.

(iii) Retain the record of calibrationtests for 1 year from the date of the test.Records shall be retained at a surfacelocation at the mine and made availablefor inspection by authorizedrepresentatives of the Secretary and therepresentative of miners.

(b)(1) When the methaneconcentration at any methane monitorreaches 1.0 percent the monitor shallgive a warning signal.

(2) The warning signal device of themethane monitor shall be visible to aperson who can deenergize theequipment on which the monitor ismounted.

(c) The methane monitor shallautomatically deenergize the machineon which it is mounted when—

(1) The methane concentration at anymethane monitor reaches 2.0 percent; or

(2) The monitor is not operatingproperly.

§ 75.343 Underground shops.(a) Underground shops shall be

equipped with an automatic firesuppression system meeting therequirements of § 75.1107–3 through§ 75.1107–16, or be enclosed in anoncombustible structure or area.

(b) Underground shops shall beventilated with intake air that is courseddirectly into a return air course.

§ 75.344 Compressors.(a) Except compressors that are

components of equipment such aslocomotives and rock dusting machinesand compressors of less than 5horsepower, electrical compressorsincluding those that may startautomatically shall be:

(1) Continuously attended by a persondesignated by the operator who can seethe compressor at all times during itsoperation. Any designated personattending the compressor shall becapable of activating the firesuppression system and deenergizing orshutting-off the compressor in the eventof a fire; or,

(2) Enclosed in a noncombustiblestructure or area which is ventilated byintake air coursed directly into a returnair course or to the surface andequipped with sensors to monitor forheat and for carbon monoxide or smoke.The sensors shall deenergize power tothe compressor, activate a visual andaudible alarm located outside of and onthe intake side of the enclosure, andactivate doors to automatically enclosethe noncombustible structure or areawhen either of the following occurs:

(i) The temperature in thenoncombustible structure or areareaches 165 °F.


(ii) The carbon monoxideconcentration reaches 10 parts permillion above the ambient level for thearea, or the optical density of smokereaches 0.022 per meter. At least onceevery 31 days, sensors installed tomonitor for carbon monoxide shall becalibrated with a known concentrationof carbon monoxide and air sufficient toactivate the closing door, and eachsmoke sensor shall be tested todetermine that it functions correctly.

(b) Compressors, except thoseexempted in paragraph (a), shall beequipped with a heat activated firesuppression system meeting therequirements of 75.1107–3 through75.1107–16.

(c) Two portable fire extinguishers orone extinguisher having at least twicethe minimum capacity specified for aportable fire extinguisher in § 75.1100–1(e) shall be provided for eachcompressor.

(d) In addition to electricalcompressors, this section shall apply todiesel compressors.

(e) Notwithstanding the requirementsof § 75.1107–4, upon activation of anyfire suppression system used underparagraph (b) of this section, thecompressor shall be automaticallydeenergized or automatically shut off.

§ 75.350 Air courses and belt haulageentries.

In any coal mine opened after March30, 1970, the entries used as intake andreturn air courses shall be separatedfrom belt haulage entries, and eachoperator of such mine shall limit thevelocity of the air coursed through belthaulage entries to the amount necessaryto provide an adequate supply of oxygenin such entries, and to insure that the airtherein shall contain less than 1.0volume per centum of methane, andsuch air shall not be used to ventilateactive working places. Whenever anauthorized representative of theSecretary finds, in the case of any coalmine opened on or prior to March 30,1970, that has been developed withmore than two entries, that theconditions in the entries, other than belthaulage entries, are such as to permitadequately the coursing of intake orreturn air through such entries:

(a) The belt haulage entries shall notbe used to ventilate, unless such entriesare necessary to ventilate, activeworking places, and

(b) When the belt haulage entries arenot necessary to ventilate the activeworking places, the operator of suchmine shall limit the velocity of the aircoursed through the belt haulage entriesto the amount necessary to provide anadequate supply of oxygen in such

entries, and to assure that air thereinshall contain less than 1.0 volume percentum of methane.

§ 75.351 Atmospheric monitoring system(AMS).

(a) Minimum requirements. An AMSshall consist of sensors to monitor themine atmosphere and instruments at asurface location designated by theoperator to receive information from themonitoring sensors. Each AMS installedin accordance with §§ 75.323(d)(1)(ii),75.340(a)(2) and 75.362(f) shall do thefollowing:

(1) Monitor for circuit continuity andsensor function, and identify at thedesignated surface location anyactivated or malfunctioning sensor.

(2) Signal a designated surfacelocation at the mine when anyinterruption of circuit continuity occursor any sensor malfunctions.

(3) Signal affected working sectionsand the designated surface locationwhen—

(i) The carbon monoxideconcentration at any carbon monoxidesensor reaches 5 parts per million abovethe established ambient level for thatarea; or

(ii) The methane concentration at anymethane monitoring station exceeds themaximum allowable concentration asspecified for that location in § 75.323.

(4) Activate alarms at a designatedsurface location and affected workingsections when the carbon monoxideconcentration at any carbon monoxidesensor reaches 10 parts per millionabove the established ambient level forthe area or when the optical density ofsmoke at any smoke sensor reaches 0.05per meter.

(b) Return splits. (1) If used to monitorreturn air splits under § 75.362(f), AMSsensors shall monitor the mineatmosphere for percentage of methanein each return split of air from eachworking section between the lastworking place, or longwall or shortwallface, ventilated by that air split and thejunction of that return air split withanother air split, seal, or worked-outarea. If auxiliary fans and tubing areused, the sensor also shall be locatedoutby the auxiliary fan discharge.

(2) If used to monitor air splits under§ 75.323(d)(1)(ii), AMS sensors shallmonitor the mine atmosphere at thefollowing locations:

(i) In the return air course oppositethe section loading point or, if auxiliaryfans and tubing are used, in the returnair course outby the auxiliary fans anda point opposite the section loadingpoint.

(ii) Immediately inby the locationwhere the split of air meets another split

of air, or inby the location where thesplit of air is used to ventilate seals orworked-out areas.

(c) Electrical installations. If used tomonitor the intake air ventilatingunderground transformer stations,battery charging stations, substations,rectifiers, or water pumps under§ 75.340(a)(2), at least one sensor shallbe installed to monitor the mineatmosphere for carbon monoxide orsmoke at least 50 feet and no more than100 feet downstream in the direction ofair flow.

(d) Signals and alarms. (1) A persondesignated by the operator shall be at asurface location where the signals andalarms from the AMS can always beseen or heard while anyone isunderground. This person shall haveaccess to two-way communication withworking sections and with otheridentifiable duty stations underground.A mine map showing the undergroundmonitoring system shall be posted at thesurface location.

(2) If a signal from any AMS sensor isactivated, the monitor producing thesignal shall be identified, anexamination shall be made to determinethe cause of the activation, andappropriate action shall be taken.

(e) Sensors. (1) Each carbon monoxidesensor shall be capable of detectingcarbon monoxide in air at a level of ±1part per million throughout theoperating range.

(2) Each methane sensor shall becapable of detecting 1.0 percentmethane in air with an accuracy of ±0.2percent methane.

(3) Each smoke sensor shall becapable of detecting the optical densityof smoke with an accuracy of ±0.005 permeter.

(f) Testing and calibration. At leastonce every 31 days—

(1) Each carbon monoxide sensorshall be calibrated with a knownconcentration of carbon monoxide andair sufficient to activate an alarm;

(2) Each smoke sensor shall befunctionally tested;

(3) Each methane sensor shall becalibrated with a known methane-airmixture; and

(4) Each oxygen sensor shall becalibrated with air having a knownoxygen concentration.

(g) Intrinsic Safety. Components ofAMS installed in areas wherepermissible equipment is required shallbe intrinsically safe.

(h) Recordkeeping. If a signal deviceor alarm is activated, a record shall bemade of the date, time, type of sensor,and the reason for its activation. Alsothe maximum concentration detected at


the sensor producing the signal shall berecorded.

(i) Retention period. Records shall beretained for at least 1 year at a surfacelocation at the mine and made availablefor inspection by authorizedrepresentatives of the Secretary andrepresentatives of miners.

§ 75.352 Return air courses.Entries used as return air courses

shall be separated from belt haulageentries by permanent ventilationcontrols.

§ 75.360 Preshift examination.(a)(1) Except as provided in paragraph

(a)(2) of this section, a certified persondesignated by the operator shall make apreshift examination within 3 hourspreceding the beginning of any 8-hourinterval during which any person isscheduled to work or travelunderground. The operator shallestablish the 8-hour intervals of timesubject to the required preshiftexaminations. No person other thancertified examiners may enter or remainin any underground area unless apreshift examination has beencompleted for the established 8-hourperiod.

(2) Preshift examinations of areaswhere pumpers are scheduled to workor travel shall not be required prior tothe pumper entering the areas if thepumper is a certified person and thepumper conducts an examination forhazardous conditions, tests for methaneand oxygen deficiency and determines ifthe air is moving in its proper directionin the area where the pumper works ortravels. The examination of the areamust be completed before the pumperperforms any other work. A record of allhazardous conditions found by thepumper shall be made and retained inaccordance with § 75.363.

(b) The person conducting the preshiftexamination shall examine forhazardous conditions, test for methaneand oxygen deficiency, and determine ifthe air is moving in its proper directionat the following locations:

(1) Roadways, travelways and trackhaulageways where persons arescheduled, prior to the beginning of thepreshift examination, to work or travelduring the oncoming shift.

(2) Belt conveyors that will be used totransport persons during the oncomingshift and the entries in which these beltconveyors are located.

(3) Working sections and areas wheremechanized mining equipment is beinginstalled or removed, if anyone isscheduled to work on the section or inthe area during the oncoming shift. Thescope of the examination shall include

the working places, approaches toworked-out areas and ventilationcontrols on these sections and in theseareas, and the examination shall includetests of the roof, face and rib conditionson these sections and in these areas.

(4) Approaches to worked-out areasalong intake air courses and at theentries used to carry air into worked-outareas if the intake air passing theapproaches is used to ventilate workingsections where anyone is scheduled towork during the oncoming shift. Theexamination of the approaches to theworked-out areas shall be made in theintake air course immediately inby andoutby each entry used to carry air intothe worked-out area. An examination ofthe entries used to carry air into theworked-out areas shall be conducted ata point immediately inby theintersection of each entry with theintake air course.

(5) Seals along intake air courseswhere intake air passes by a seal toventilate working sections whereanyone is scheduled to work during theoncoming shift.

(6)(i) Entries and rooms developedafter November 15, 1992, and developedmore than 2 crosscuts off an intake aircourse without permanent ventilationcontrols where intake air passes throughor by these entries or rooms to reach aworking section where anyone isscheduled to work during the oncomingshift; and,

(ii) Entries and rooms developed afterNovember 15, 1992, and driven morethan 20 feet off an intake air coursewithout a crosscut and withoutpermanent ventilation controls whereintake air passes through or by theseentries or rooms to reach a workingsection where anyone is scheduled towork during the oncoming shift.

(7) Where unattended dieselequipment is to operate or areas wheretrolley wires or trolley feeder wires areto be or will remain energized duringthe oncoming shift.

(8) High spots along intake air courseswhere methane is likely to accumulate,if equipment will be operated in thearea during the shift.

(9) Underground electricalinstallations referred to in § 75.340(a),except those pumps listed in § 75.340(b)(2) through (b)(6), and areas wherecompressors subject to § 75.344 areinstalled if the electrical installation orcompressor is or will be energizedduring the shift.

(10) Other areas where work or travelduring the oncoming shift is scheduledprior to the beginning of the preshiftexamination.

(c) The person conducting the preshiftexamination shall determine the volume

of air entering each of the followingareas if anyone is scheduled to work inthe areas during the oncoming shift:

(1) In the last open crosscut of eachset of entries or rooms on each workingsection and areas where mechanizedmining equipment is being installed orremoved. The last open crosscut is thecrosscut in the line of pillars containingthe permanent stoppings that separatethe intake air courses and the return aircourses.

(2) On each longwall or shortwall inthe intake entry or entries at the intakeend of the longwall or shortwall faceimmediately outby the face and thevelocity of air at each end of the face atthe locations specified in the approvedventilation plan.

(3) At the intake end of any pillarline—

(i) If a single split of air is used, in theintake entry furthest from the return aircourse, immediately outby the first opencrosscut outby the line of pillars beingmined; or

(ii) If a split system is used, in theintake entries of each split immediatelyinby the split point.

(d) The district manager may requirethe certified person to examine otherareas of the mine or examine for otherhazards during the preshiftexamination.

(e) Certification. At each workingplace examined, the person doing thepreshift examination shall certify byinitials, date, and the time, that theexamination was made. In areasrequired to be examined outby aworking section, the certified personshall certify by initials, date, and thetime at enough locations to show thatthe entire area has been examined.

(f) Recordkeeping. A record of theresults of each preshift examination,including a record of hazardousconditions and their locations found bythe examiner during each examinationand of the results and locations of airand methane measurements, shall bemade on the surface before any persons,other than certified persons conductingexaminations required by this subpart,enter any underground area of the mine.The results of methane tests shall berecorded as the percentage of methanemeasured by the examiner. The recordshall be made by the certified personwho made the examination or by aperson designated by the operator. If therecord is made by someone other thanthe examiner, the examiner shall verifythe record by initials and date by or atthe end of the shift for which theexamination was made. A record shallalso be made by a certified person of theaction taken to correct hazardousconditions found during the preshift


examination. All preshift and correctiveaction records shall be countersigned bythe mine foreman or equivalent mineofficial by the end of the mine foreman’sor equivalent mine official’s nextregularly scheduled working shift. Therecords required by this section shall bemade in a secure book that is notsusceptible to alteration orelectronically in a computer system soas to be secure and not susceptible toalteration.

(g) Retention period. Records shall beretained at a surface location at the minefor at least 1 year and shall be madeavailable for inspection by authorizedrepresentatives of the Secretary and therepresentative of miners.

§ 75.361 Supplemental examination.(a) Except for certified persons

conducting examinations required bythis subpart, within 3 hours beforeanyone enters an area in which apreshift examination has not been madefor that shift, a certified person shallexamine the area for hazardousconditions, determine whether the air istraveling in its proper direction and atits normal volume, and test for methaneand oxygen deficiency.

(b) Certification. At each workingplace examined, the person making thesupplemental examination shall certifyby initials, date, and the time, that theexamination was made. In areasrequired to be examined outby aworking section, the certified personshall certify by initials, date, and thetime at enough locations to show thatthe entire area has been examined.

§ 75.362 On-shift examination.(a) (1) At least once during each shift,

or more often if necessary for safety, acertified person designated by theoperator shall conduct an on-shiftexamination of each section whereanyone is assigned to work during theshift and any area where mechanizedmining equipment is being installed orremoved during the shift. The certifiedperson shall check for hazardousconditions, test for methane and oxygendeficiency, and determine if the air ismoving in its proper direction.

(2) A person designated by theoperator shall conduct an examinationto assure compliance with the respirabledust control parameters specified in themine ventilation plan. In thoseinstances when a shift change isaccomplished without an interruptionin production on a section, theexamination shall be made anytimewithin 1 hour of the shift change. Inthose instances when there is aninterruption in production during theshift change, the examination shall be

made before production begins on asection. Deficiencies in dust controlsshall be corrected before productionbegins or resumes. The examinationshall include air quantities andvelocities, water pressures and flowrates, excessive leakage in the waterdelivery system, water spray numbersand orientations, section ventilation andcontrol device placement, and any otherdust suppression measures required bythe ventilation plan. Additionalmeasurements of the air velocity andquantity, water pressure and flow ratesare not required if continuousmonitoring of these controls is used andindicates that the dust controls arefunctioning properly.

(b) During each shift that coal isproduced, a certified person shallexamine for hazardous conditions alongeach belt conveyor haulageway where abelt conveyor is operated. Thisexamination may be conducted at thesame time as the preshift examination ofbelt conveyors and belt conveyorhaulageways, if the examination isconducted within 3 hours before theoncoming shift.

(c) Persons conducting the on-shiftexamination shall determine at thefollowing locations:

(1) The volume of air in the last opencrosscut of each set of entries or roomson each section and areas wheremechanized mining equipment is beinginstalled or removed. The last opencrosscut is the crosscut in the line ofpillars containing the permanentstoppings that separate the intake aircourses and the return air courses.

(2) The volume of air on a longwallor shortwall, including areas wherelongwall or shortwall equipment isbeing installed or removed, in the intakeentry or entries at the intake end of thelongwall or shortwall.

(3) The velocity of air at each end ofthe longwall or shortwall face at thelocations specified in the approvedventilation plan.

(4) The volume of air at the intake endof any pillar line—

(i) Where a single split of air is usedin the intake entry furthest from thereturn air course immediately outby thefirst open crosscut outby the line ofpillars being mined; or

(ii) Where a split system is used in theintake entries of each split immediatelyinby the split point.

(d) (1) A qualified person shall maketests for methane—

(i) At the start of each shift at eachworking place before electricallyoperated equipment is energized; and

(ii) Immediately before equipment isenergized, taken into, or operated in aworking place; and

(iii) At 20-minute intervals, or moreoften if required in the approvedventilation plan at specific locations,during the operation of equipment inthe working place.

(2) These methane tests shall be madeat the face from under permanent roofsupport, using extendable probes orother acceptable means. When longwallor shortwall mining systems are used,these methane tests shall be made at theshearer, the plow, or the cutting head.When mining has been stopped for morethan 20 minutes, methane tests shall beconducted prior to the start up ofequipment.

(e) If auxiliary fans and tubing areused, they shall be inspected frequently.

(f) During each shift that coal isproduced and at intervals not exceeding4 hours, tests for methane shall be madeby a certified person or by anatmospheric monitoring system (AMS)in each return split of air from eachworking section between the lastworking place, or longwall or shortwallface, ventilated by that split of air andthe junction of the return air split withanother air split, seal, or worked-outarea. If auxiliary fans and tubing areused, the tests shall be made at alocation outby the auxiliary fandischarge.

(g) Certification. (1) The personconducting the on-shift examination inbelt haulage entries shall certify byinitials, date, and time that theexamination was made. The certifiedperson shall certify by initials, date, andthe time at enough locations to showthat the entire area has been examined.

(2) The person directing the on-shiftexamination to assure compliance withthe respirable dust control parametersspecified in the mine ventilation planshall certify by initials, date, and timethat the examination was made.

§ 75.363 Hazardous conditions; posting,correcting and recording.

(a) Any hazardous condition found bythe mine foreman or equivalent mineofficial, assistant mine foreman orequivalent mine official, or othercertified persons designated by theoperator for the purposes of conductingexaminations under this subpart D, shallbe posted with a conspicuous dangersign where anyone entering the areaswould pass. A hazardous condition,other than one detected during apreshift examination or an examinationconducted following a fan stoppage andrestart under § 75.313(d)(1)(i), shall becorrected immediately or the area shallremain posted until the hazardouscondition is corrected. If the conditioncreates an imminent danger, everyoneexcept those persons referred to in


section 104(c) of the Act shall bewithdrawn from the area affected to asafe area until the hazardous conditionis corrected. Only persons designated bythe operator to correct or evaluate thecondition may enter the posted area.

(b) A record shall be made of anyhazardous condition found. This recordshall be kept in a book maintained forthis purpose on the surface at the mine.The record shall be made by thecompletion of the shift on which thehazardous condition is found and shallinclude the nature and location of thehazardous condition and the correctiveaction taken. This record shall not berequired for shifts when no hazardousconditions are found or for hazardousconditions found during the preshift orweekly examinations inasmuch as theseexaminations have separaterecordkeeping requirements.

(c) The record shall be made by thecertified person who conducted theexamination or a person designated bythe operator. If made by a person otherthan the certified person, the certifiedperson shall verify the record by initialsand date by or at the end of the shift forwhich the examination was made.Records shall be countersigned by themine foreman or equivalent mineofficial by the end of the mine foreman’sor equivalent mine official’s nextregularly scheduled working shift. Therecord shall be made in a secure bookthat is not susceptible to alteration orelectronically in a computer system soas to be secure and not susceptible toalteration.

(d) Retention period. Records shall beretained at a surface location at the minefor at least 1 year and shall be madeavailable for inspection by authorizedrepresentatives of the Secretary and therepresentative of miners.

§ 75.364 Weekly examination.(a) Worked-out areas. (1) At least

every 7 days, a certified person shallexamine unsealed worked-out areaswhere no pillars have been recovered bytraveling to the area of deepestpenetration; measuring methane andoxygen concentrations and air quantitiesand making tests to determine if the airis moving in the proper direction in thearea. The locations of measurementpoints where tests and measurementswill be performed shall be included inthe mine ventilation plan and shall beadequate in number and location toassure ventilation and air quality in thearea. Air quantity measurements shallalso be made where the air enters andleaves the worked-out area. Analternative method of evaluating theventilation of the area may be approvedin the ventilation plan.

(2) At least every 7 days, a certifiedperson shall evaluate the effectivenessof bleeder systems required by § 75.334as follows:

(i) Measurements of methane andoxygen concentrations and air quantityand a test to determine if the air ismoving in its proper direction shall bemade where air enters the worked-outarea.

(ii) Measurements of methane andoxygen concentrations and air quantityand a test to determine if the air ismoving in the proper direction shall bemade immediately before the air entersa return split of air.

(iii) At least one entry of each set ofbleeder entries used as part of a bleedersystem under § 75.334 shall be traveledin its entirety. Measurements ofmethane and oxygen concentrations andair quantities and a test to determine ifthe air is moving in the proper directionshall be made at the measurement pointlocations specified in the mineventilation plan to determine theeffectiveness of the bleeder system.

(iv) In lieu of the requirements ofparagraphs (a)(2)(i) and (iii) of thissection, an alternative method ofevaluation may be specified in theventilation plan provided the alternativemethod results in proper evaluation ofthe effectiveness of the bleeder system.

(b) Hazardous conditions. At leastevery 7 days, an examination forhazardous conditions at the followinglocations shall be made by a certifiedperson designated by the operator:

(1) In at least one entry of each intakeair course, in its entirety, so that theentire air course is traveled.

(2) In at least one entry of each returnair course, in its entirety, so that theentire air course is traveled.

(3) In each longwall or shortwalltravelway in its entirety, so that theentire travelway is traveled.

(4) At each seal along return andbleeder air courses and at each sealalong intake air courses not examinedunder § 75.360(b)(5).

(5) In each escapeway so that theentire escapeway is traveled.

(6) On each working section notexamined under § 75.360(b)(3) duringthe previous 7 days.

(7) At each water pump not examinedduring a preshift examinationconducted during the previous 7 days.

(c) Measurements and tests. At leastevery 7 days, a certified person shall—

(1) Determine the volume of airentering the main intakes and in eachintake split;

(2) Determine the volume of air andtest for methane in the last opencrosscut in any pair or set of developingentries or rooms, in the return of each

split of air immediately before it entersthe main returns, and where the airleaves the main returns; and

(3) Test for methane in the returnentry nearest each set of sealsimmediately after the air passes theseals.

(d) Hazardous conditions shall becorrected immediately. If the conditioncreates an imminent danger, everyoneexcept those persons referred to in§ 104(c) of the Act shall be withdrawnfrom the area affected to a safe area untilthe hazardous condition is corrected.

(e) The weekly examination may beconducted at the same time as thepreshift or on-shift examinations.

(f) (1) The weekly examination is notrequired during any 7 day period inwhich no one enters any undergroundarea of the mine.

(2) Except for certified personsrequired to make examinations, no oneshall enter any underground area of themine if a weekly examination has notbeen completed within the previous 7days.

(g) Certification. The person makingthe weekly examinations shall certify byinitials, date, and the time that theexamination was made. Certificationsand times shall appear at enoughlocations to show that the entire areahas been examined.

(h) Recordkeeping. At the completionof any shift during which a portion ofa weekly examination is conducted, arecord of the results of each weeklyexamination, including a record ofhazardous conditions found during eachexamination and their locations, thecorrective action taken, and the resultsand location of air and methanemeasurements, shall be made. Theresults of methane tests shall berecorded as the percentage of methanemeasured by the examiner. The recordshall be made by the person making theexamination or a person designated bythe operator. If made by a person otherthan the examiner, the examiner shallverify the record by the initials and dateby or at the end of the shift for whichthe examination was made. The recordshall be countersigned by the mineforeman or equivalent mine official bythe end of the mine foreman’s orequivalent mine official’s next regularlyscheduled working shift. The recordsrequired by this section shall be madein a secure book that is not susceptibleto alteration or electronically in acomputer system so as to be secure andnot susceptible to alteration.

(i) Retention period. Records shall beretained at a surface location at the minefor at least 1 year and shall be madeavailable for inspection by authorized


representatives of the Secretary and therepresentative of miners.

§ 75.370 Mine ventilation plan; submissionand approval.

(a) (1) The operator shall develop andfollow a ventilation plan approved bythe district manager. The plan shall bedesigned to control methane andrespirable dust and shall be suitable tothe conditions and mining system at themine. The ventilation plan shall consistof two parts, the plan content asprescribed in § 75.371 and theventilation map with information asprescribed in § 75.372. Only that portionof the map which contains informationrequired under § 75.371 will be subjectto approval by the district manager.

(2) The proposed ventilation plan andany revision to the plan shall besubmitted in writing to the districtmanager. When revisions to aventilation plan are proposed, only therevised pages, maps, or sketches of theplan need to be submitted. Whenrequired in writing by the districtmanager, the operator shall submit afully revised plan by consolidating theplan and all revisions in an orderlymanner and by deleting all outdatedmaterial.

(3) (i) The mine operator shall notifythe representative of miners at least 5days prior to submission of a mineventilation plan and any revision to amine ventilation plan. If requested, themine operator shall provide a copy tothe representative of miners at the timeof notification. In the event of asituation requiring immediate action ona plan revision, notification of therevision shall be given, and if requested,a copy of the revision shall be provided,to the representative of miners by theoperator at the time of submittal;

(ii) A copy of the proposed ventilationplan, and a copy of any proposedrevision, submitted for approval shall bemade available for inspection by therepresentative of miners; and

(iii) A copy of the proposedventilation plan, and a copy of anyproposed revision, submitted forapproval shall be posted on the minebulletin board at the time of submittal.The proposed plan or proposed revisionshall remain posted until it is approved,withdrawn or denied.

(b) Following receipt of the proposedplan or proposed revision, therepresentative of miners may submittimely comments to the districtmanager, in writing, for considerationduring the review process. A copy ofthese comments shall also be providedto the operator by the district managerupon request.

(c) (1) The district manager will notifythe operator in writing of the approvalor denial of approval of a proposedventilation plan or proposed revision. Acopy of this notification will be sent tothe representative of miners by thedistrict manager.

(2) If the district manager deniesapproval of a proposed plan or revision,the deficiencies of the plan or revisionshall be specified in writing and theoperator will be provided anopportunity to discuss the deficiencieswith the district manager.

(d) No proposed ventilation plan shallbe implemented before it is approved bythe district manager. Any intentionalchange to the ventilation system thatalters the main air current or any splitof the main air current in a manner thatcould materially affect the safety andhealth of the miners, or any change tothe information required in § 75.371shall be submitted to and approved bythe district manager beforeimplementation.

(e) Before implementing an approvedventilation plan or a revision to aventilation plan, persons affected by therevision shall be instructed by theoperator in its provisions.

(f) The approved ventilation plan andany revisions shall be—

(1) Provided upon request to therepresentative of miners by the operatorfollowing notification of approval;

(2) Made available for inspection bythe representative of miners; and

(3) Posted on the mine bulletin boardwithin 1 working day followingnotification of approval. The approvedplan and revisions shall remain postedon the bulletin board for the period thatthey are in effect.

(g) The ventilation plan for each mineshall be reviewed every 6 months by anauthorized representative of theSecretary to assure that it is suitable tocurrent conditions in the mine.

§ 75.371 Mine ventilation plan; contents.

The mine ventilation plan shallcontain the information described belowand any additional provisions requiredby the district manager:

(a) The mine name, company name,mine identification number, and thename of the individual submitting theplan information.

(b) Planned main mine fan stoppages,other than those scheduled for testing,maintenance or adjustment, includingprocedures to be followed during thesestoppages and subsequent restarts (see§ 75.311(a)) and the type of device to beused for monitoring main mine fanpressure, if other than a pressurerecording device (see 75.310(a)(4)).

(c) Methods of protecting main minefans and associated components fromthe forces of an underground explosionif a 15-foot offset from the nearest sideof the mine opening is not provided (see§ 75.310(a)(6)); and the methods ofprotecting main mine fans and intake airopenings if combustible material will bewithin 100 feet of the area surroundingthe fan or these openings (see§ 75.311(f)).

(d) Persons that will be permitted toenter the mine, the work these personswill do while in the mine, and electricpower circuits that will be energizedwhen a back-up fan system is used thatdoes not provide the ventilatingquantity provided by the main mine fan(see § 75.311(c)).

(e) The locations and operatingconditions of booster fans installed inanthracite mines (see § 75.302).

(f) Section and face ventilationsystems used, including drawingsillustrating how each system is used,and a description of each different dustsuppression system used on equipmenton working sections.

(g) Locations where the air quantitiesmust be greater than 3,000 cubic feet perminute (see § 75.325(a)(1)).

(h) In anthracite mines, locationswhere the air quantities must be greaterthan 1,500 cubic feet per minute (see§ 75.325(e)(1)).

(i) Working places and working facesother than those where coal is being cut,mined, drilled for blasting or loaded,where a minimum air quantity will bemaintained, and the air quantity at thoselocations (see § 75.325(a)(1)).

(j) The operating volume of machinemounted dust collectors or diffuser fans,if used (see § 75.325(a)(3)).

(k) The minimum mean entry airvelocity in exhausting face ventilationsystems where coal is being cut, mined,drilled for blasting, or loaded, if thevelocity will be less than 60 feet perminute. Other working places wherecoal is not being cut, mined, drilled forblasting or loaded, where at least 60 feetper minute or some other minimummean entry air velocity will bemaintained (see § 75.326).

(l) The maximum distance if greaterthan 10 feet from each working face atwhich face ventilation control deviceswill be installed (see § 75.330(b)(2)). Theworking places other than those wherecoal is being cut, mined, drilled forblasting or loaded, where faceventilation control devices will be used(see § 75.330(b)(1)(ii).

(m) The volume of air required in thelast open crosscut or the quantity of airreaching the pillar line if greater than9,000 cubic feet per minute (see§ 75.325(b)).


(n) In anthracite mines, the volume ofair required in the last open crosscut orthe quantity of air reaching the pillarline if greater than 5,000 cubic feet perminute (see § 75.325(e)(2)).

(o) Locations where separations ofintake and return air courses will bebuilt and maintained to other than thethird connecting crosscut outby eachworking face (see § 75.333(b)(1)).

(p) The volume of air required at theintake to the longwall sections, ifdifferent than 30,000 cubic feet perminute (see § 75.325(c)).

(q) The velocities of air on a longwallor shortwall face, and the locationswhere the velocities must be measured(see § 75.325(c)(2)).

(r) The minimum quantity of air thatwill be provided during the installationand removal of mechanized miningequipment, the location where thisquantity will be provided, and theventilation controls that will be used.(see § 75.325(d)).

(s) The locations and frequency of themethane tests if required more often by§ 75.362(d)(1)(iii) (see § 75.362(d)(1)(iii).

(t) The locations where samples for‘‘designated areas’’ will be collected,including the specific location of eachsampling device, and the respirable dustcontrol measures used at the dustgenerating sources for these locations(see § 70.208 of this chapter).

(u) The methane and dust controlsystems at underground dumps,crushers, transfer points, andhaulageways.

(v) Areas in trolley haulage entrieswhere the air velocity will be greaterthan 250 feet per minute and thevelocity in these areas (see § 75.327(b)).

(w) Locations where entries will beadvanced less than 20 feet from the inbyrib without a crosscut being providedwhere a line brattice will be required.(see § 75.333(g)).

(x) A description of the bleedersystem to be used, including its design(see § 75.334).

(y) The means for determining theeffectiveness of bleeder systems (see§ 75.334(c)(2)).

(z) The locations where measurementsof methane and oxygen concentrationsand air quantities and tests to determinewhether the air is moving in the properdirection will be made to evaluate theventilation of nonpillared worked-outareas (see § 75.364 (a)(1)) and theeffectiveness of bleeder systems (see§ 75.364 (a)(2)(iii). Alternative methodsof evaluation of the effectiveness ofbleeder systems (§ 75.364 (a)(2)(iv)).

(aa) The means for adequatelymaintaining bleeder entries free of

obstructions such as roof falls andstanding water (see § 75.334(c)(3)).

(bb) The location of ventilationdevices such as regulators, stoppingsand bleeder connectors used to controlair movement through worked-out areas(see § 75.334(c)(4)). The location andsequence of construction of proposedseals for each worked-out area. (see§ 75.334(e)).

(cc) In mines with a demonstratedhistory of spontaneous combustion: adescription of the measures that will beused to detect methane, carbonmonoxide, and oxygen concentrationduring and after pillar recovery and inworked-out areas where no pillars havebeen recovered (see § 75.334(f)(1); and,the actions which will be taken toprotect miners from the hazardsassociated with spontaneouscombustion (see § 75.334(f)(2). If ableeder system will not be used, themethods that will be used to controlspontaneous combustion,accumulations of methane-air mixtures,and other gases, dusts, and fumes in theworked-out area (see § 75.334(f)(3)).

(dd) The location of all horizontaldegasification holes that are longer than1,000 feet and the location of all verticaldegasification holes.

(ee) If methane drainage systems areused, a detailed sketch of each system,including a description of safetyprecautions used with the systems.

(ff) A description of the methods andmaterials to be used to seal worked-outareas if those methods or materials willbe different from those specified by§ 75.335(a)(1).

(gg) The alternative location for theadditional sensing device if the devicewill not be installed on the longwallshearing machine (see § 75.342(a)(2)).

(hh) The ambient level in parts permillion of carbon monoxide, and themethod for determining the ambientlevel, in all areas where carbonmonoxide sensors are installed.

(ii) The distance that separationbetween the primary escapeway and thebelt or track haulage entries will bemaintained if other than to the firstconnecting crosscut outby the sectionloading point (see § 75.380(g)).

(jj) In anthracite mines, thedimensions of escapeways where thepitch of the coal seam does not permitescapeways to be maintained 4 feet by5 feet and the locations where thesedimensions must be maintained (see§ 75.381(c)(4)).

§ 75.372 Mine ventilation map.(a)(1) At intervals not exceeding 12

months, the operator shall submit to thedistrict manager 3 copies of an up-to-date map of the mine drawn to a scale

of not less than 100 nor more than 500feet to the inch. A registered engineer ora registered surveyor shall certify thatthe map is accurate.

(2) In addition to the informationalrequirements of this section the mapmay also be used to depict and explainplan contents that are required in§ 75.371. Information shown on the mapto satisfy the requirements of § 75.371shall be subject to approval by thedistrict manager.

(b) The map shall contain thefollowing information:

(1) The mine name, company name,mine identification number, a legendidentifying the scale of the map andsymbols used, and the name of theindividual responsible for theinformation on the map.

(2) All areas of the mine, includingsealed and unsealed worked-out areas.

(3) All known mine workings that arelocated in the same coalbed within1,000 feet of existing or projectedworkings. These workings may beshown on a mine map with a scale otherthan that required by paragraph (a) ofthis section, if the scale does not exceed2,000 feet to the inch and is specified onthe map.

(4) The locations of all known mineworkings underlying and overlying themine property and the distance betweenthe mine workings.

(5) The locations of all known oil andgas wells and all known drill holes thatpenetrate the coalbed being mined.

(6) The locations of all main minefans, installed backup fans and motors,and each fan’s specifications, includingsize, type, model number, manufacturer,operating pressure, motor horsepower,and revolutions per minute.

(7) The locations of all surface mineopenings and the direction and quantityof air at each opening.

(8) The elevation at the top andbottom of each shaft and slope, andshaft and slope dimensions, includingdepth and length.

(9) The direction of air flow in allunderground areas of the mine.

(10) The locations of all activeworking sections and the four-digitidentification number for eachmechanized mining unit (MMU).

(11) The location of all escapeways.(12) The locations of all ventilation

controls, including permanentstoppings, overcasts, undercasts,regulators, seals, airlock doors,haulageway doors and other doors,except temporary ventilation controlson working sections.

(13) The direction and quantity ofair—

(i) Entering and leaving each split;(ii) In the last open crosscut of each

set of entries and rooms; and


(iii) At the intake end of each pillarline, including any longwall orshortwall.

(14) Projections for at least 12 monthsof anticipated mine development,proposed ventilation controls, proposedbleeder systems, and the anticipatedlocation of intake and return air courses,belt entries, and escapeways.

(15) The locations of existing methanedrainage systems.

(16) The locations of all atmosphericmonitoring system sensors.

(17) Contour lines that pass throughwhole number elevations of the coalbedbeing mined. These lines shall bespaced at 10-foot elevation levels unlessa wider spacing is permitted by thedistrict manager.

(18) The location of proposed seals foreach worked-out area.

(19) The entry height, velocity anddirection of the air current at or near themidpoint of each belt flight where theheight and width of the entry arerepresentative of the belt haulage entry.

(20) The location and designation ofair courses that have been redesignatedfrom intake to return for the purpose ofventilation of structures, areas orinstallations that are required by thissubpart D to be ventilated to return aircourses, and for ventilation of seals.

(c) The mine map required by§ 75.1200 may be used to satisfy therequirements for the ventilation map,provided that all the informationrequired by this section is contained onthe map.

§ 75.373 Reopening mines.After a mine is abandoned or declared

inactive, and before it is reopened,mining operations shall not begin untilMSHA has been notified and hascompleted an inspection.

§ 75.380 Escapeways; bituminous andlignite mines.

(a) Except in situations addressed in§ 75.381, § 75.385 and § 75.386, at leasttwo separate and distinct travelablepassageways shall be designated asescapeways and shall meet therequirements of this section.

(b) (1) Escapeways shall be providedfrom each working section, and eacharea where mechanized miningequipment is being installed orremoved, continuous to the surfaceescape drift opening or continuous tothe escape shaft or slope facilities to thesurface.

(2) During equipment installation,these escapeways shall begin at theprojected location for the sectionloading point. During equipmentremoval, they shall begin at the locationof the last loading point.

(c) The two separate and distinctescapeways required by this sectionshall not end at a common shaft, slope,or drift opening, except that multiplecompartment shafts or slopes separatedby walls constructed of noncombustiblematerial may be used as separate anddistinct passageways.

(d) Each escapeway shall be—(1) Maintained in a safe condition to

always assure passage of anyone,including disabled persons;

(2) Clearly marked to show the routeand direction of travel to the surface;

(3) Maintained to at least a height of5 feet from the mine floor to the mineroof, excluding the thickness of any roofsupport, except that the escapewaysshall be maintained to at least the heightof the coalbed, excluding the thicknessof any roof support, where the coalbedis less than 5 feet. In areas of mineswhere escapeways pass through doors,the height may be less than 5 feet,provided that sufficient height ismaintained to enable miners, includingdisabled persons, to escape quickly inan emergency. In areas of minesdeveloped before November 16, 1992,where escapeways pass over or underovercasts or undercasts, the height maybe less than 5 feet provided thatsufficient height is maintained to enableminers, including disabled persons, toescape quickly in an emergency. Whenthere is a need to determine whethersufficient height is provided, MSHAmay require a stretcher test where 4persons carry a miner through the areain question on a stretcher;

(4) Maintained at least 6 feet wideexcept—

(i) Where necessary supplemental roofsupport is installed, the escapeway shallnot be less than 4 feet wide; or

(ii) Where the route of travel passesthrough doors or other permanentventilation controls, the escapewayshall be at least 4 feet wide to enableminers to escape quickly in anemergency, or

(iii) Where the alternate escapewaypasses through doors or otherpermanent ventilation controls or wheresupplemental roof support is requiredand sufficient width is maintained toenable miners, including disabledpersons, to escape quickly in anemergency. When there is a need todetermine whether sufficient width isprovided, MSHA may require a stretchertest where 4 persons carry a minerthrough the area in question on astretcher, or

(iv) Where mobile equipment nearworking sections, and other equipmentessential to the ongoing operation oflongwall sections, is necessary duringnormal mining operations, such as

material cars containing rock dust orroof control supplies, or is to be used forthe evacuation of miners off the sectionin the event of an emergency. In anyinstance, escapeways shall be ofsufficient width to enable miners,including disabled persons, to escapequickly in an emergency. When there isa need to determine whether sufficientwidth is provided, MSHA may requirea stretcher test where 4 persons carry aminer through the area in question ona stretcher;

(5) Located to follow the most direct,safe and practical route to the nearestmine opening suitable for the safeevacuation of miners; and

(6) Provided with ladders, stairways,ramps, or similar facilities where theescapeways cross over obstructions.

(e) Surface openings shall beadequately protected to prevent surfacefires, fumes, smoke, and flood waterfrom entering the mine.

(f) Primary escapeway. (1) Oneescapeway that is ventilated with intakeair shall be designated as the primaryescapeway.

(2) Paragraphs (f)(3) through (f)(7) ofthis section apply as follows:

(i) To all areas of a primary escapewaydeveloped on or after November 16,1992;

(ii) Effective as of March 11, 1997, toall areas of a primary escapewaydeveloped between March 30, 1970 andNovember 16, 1992; and

(iii) Effective as of March 11, 1997, toall areas of the primary escapewaydeveloped prior to March 30, 1970where separation of the belt and trolleyhaulage entries from the primaryescapeway existed prior to November16, 1992.

(3) The following equipment is notpermitted in the primary escapeway:

(i) Unattended operating dieselequipment without an automatic firesuppression system.

(ii) Mobile equipment hauling coalexcept for hauling coal incidental tocleanup or maintenance of the primaryescapeway.

(iii) Compressors, except—(A) Compressors necessary to

maintain the escapeway in safe,travelable condition;

(B) Compressors that are componentsof equipment such as locomotives androck dusting machines; and

(C) Compressors of less than fivehorsepower.

(iv) Underground transformerstations, battery charging stations,substations, and rectifiers except—

(A) Where necessary to maintain theescapeway in safe, travelable condition;and

(B) Battery charging stations andrectifiers and power centers with


transformers that are either dry-type orcontain nonflammable liquid, providedthey are located on or near a workingsection and are moved as the sectionadvances or retreats.

(v) Water pumps, except—(A) Water pumps necessary to

maintain the escapeway in safe,travelable condition;

(B) Submersible pumps;(C) Permissible pumps and associated

permissible switchgear;(D) Pumps located on or near a

working section that are moved as thesection advances or retreats;

(E) Pumps installed in anthracitemines; and

(F) Small portable pumps.(4) Mobile equipment operated in the

primary escapeway, except forcontinuous miners and as provided inparagraphs (f)(5), (f)(6), and (f)(7) of thissection, shall be equipped with a firesuppression system installed accordingto §§ 75.1107–3 through 75.1107–16 thatis—

(i) Manually operated and attendedcontinuously by a person trained in thesystems function and use, or

(ii) A multipurpose dry chemical typecapable of both automatic and manualactivation.

(5) Personnel carriers and smallmobile equipment designed and usedonly for carrying people and small handtools may be operated in primaryescapeways if—

(i) The equipment is provided with amultipurpose dry chemical type firesuppression system capable of bothautomatic and manual activation, andthe suppression system is suitable forthe intended application and is listed orapproved by a nationally recognizedindependent testing laboratory, or,

(ii) Battery powered and providedwith two 10 pound multipurpose drychemical portable fire extinguishers.

(6) Notwithstanding the requirementsof paragraph (f)(3)(i), mobile equipmentnot provided with a fire suppressionsystem may operate in the primaryescapeway if no one is inby except thosepersons directly engaged in using ormoving the equipment.

(7) Notwithstanding the requirementsof paragraph (f)(3)(i), mobile equipmentdesignated and used only as emergencyvehicles or ambulances, may beoperated in the primary escapewaywithout fire suppression systems.

(g) Except where separation of beltand trolley haulage entries fromdesignated escapeways did not existbefore November 15, 1992, the primaryescapeway shall be separated from beltand trolley haulage entries for its entirelength, to and including the firstconnecting crosscut outby each loading

point except when a greater or lesserdistance for this separation is specifiedand approved in the ventilation planand does not pose a hazard to miners.

(h) Alternate escapeway. Oneescapeway shall be designated as thealternate escapeway. The alternateescapeway shall be separated from theprimary escapeway for its entire length,except that the alternate and primaryescapeways may be ventilated from acommon intake air shaft or slopeopening.

(i) Mechanical escape facilities shallbe provided and maintained for—

(1) Each shaft that is part of adesignated escapeway and is greaterthan 50 feet in depth; and

(2) Each slope from the coal seam tothe surface that is part of a designatedescapeway and is inclined more than 9degrees from the horizontal.

(j) Within 30 minutes after minepersonnel on the surface have beennotified of an emergency requiringevacuation, mechanical escape facilitiesprovided under paragraph (i) of thissection shall be operational at thebottom of shaft and slope openings thatare part of escapeways.

(k) Except where automaticallyactivated hoisting equipment is used,the bottom of each shaft or slopeopening that is part of a designatedescapeway shall be equipped with ameans of signaling a surface locationwhere a person is always on duty whenanyone is underground. When the signalis activated or the evacuation of personsunderground is necessary, the personshall assure that mechanical escapefacilities are operational as required byparagraph (j) of this section.

(l) (1) Stairways or mechanical escapefacilities shall be installed in shafts thatare part of the designated escapewaysand that are 50 feet or less in depth,except ladders may be used in shaftsthat are part of the designatedescapeways and that are 5 feet or less indepth.

(2) Stairways shall be constructed ofconcrete or metal, set on an angle not toexceed 45 degrees from the horizontal,and equipped on the open side withhandrails. In addition, landingplatforms that are at least 2 feet by 4 feetshall be installed at intervals not toexceed 20 vertical feet on the stairwaysand equipped on the open side withhandrails.

(3) Ladders shall be constructed ofmetal, anchored securely, and set on anangle not to exceed 60 degrees from thehorizontal.

(m) A travelway designed to preventslippage shall be provided in slope anddrift openings that are part of designated

escapeways, unless mechanical escapefacilities are installed.

§ 75.381 Escapeways; anthracite mines.

(a) Except as provided in §§ 75.385and 75.386, at least two separate anddistinct travelable passageways shall bedesignated as escapeways and shallmeet the requirements of this section.

(b) Escapeways shall be providedfrom each working section continuousto the surface.

(c) Each escapeway shall be—(1) Maintained in a safe condition to

always assure passage of anyone,including disabled persons;

(2) Clearly marked to show the routeof travel to the surface;

(3) Provided with ladders, stairways,ramps, or similar facilities where theescapeways cross over obstructions; and

(4) Maintained at least 4 feet wide by5 feet high. If the pitch or thickness ofthe coal seam does not permit thesedimensions to be maintained otherdimensions may be approved in theventilation plan.

(d) Surface openings shall beadequately protected to prevent surfacefires, fumes, smoke, and flood waterfrom entering the mine.

(e) Primary escapeway. Oneescapeway that shall be ventilated withintake air shall be designated as theprimary escapeway.

(f) Alternate escapeway. Oneescapeway that shall be designated asthe alternate escapeway shall beseparated from the primary escapewayfor its entire length.

(g) Mechanical escape facilities shallbe provided—

(1) For each shaft or slope openingthat is part of a primary escapeway; and

(2) For slopes that are part ofescapeways, unless ladders areinstalled.

(h) Within 30 minutes after minepersonnel on the surface have beennotified of an emergency requiringevacuation, mechanical escape facilitiesshall be operational at the bottom ofeach shaft and slope opening that is partof an escapeway.

(i) Except where automaticallyactivated hoisting equipment is used,the bottom of each shaft or slopeopening that is part of a primaryescapeway shall be equipped with ameans of signaling a surface locationwhere a person is always on duty whenanyone is underground. When the signalis activated or the evacuation ofpersonnel is necessary, the person onduty shall assure that mechanicalescape facilities are operational asrequired by paragraph (h) of thissection.


§ 75.382 Mechanical escape facilities.(a) Mechanical escape facilities shall

be provided with overspeed, overwind,and automatic stop controls.

(b) Every mechanical escape facilitywith a platform, cage, or other deviceshall be equipped with brakes that canstop the fully loaded platform, cage, orother device.

(c) Mechanical escape facilities,including automatic elevators, shall beexamined weekly. The weeklyexamination of this equipment may beconducted at the same time as a dailyexamination required by § 75.1400–3.

(1) The weekly examination shallinclude an examination of the headgear,connections, links and chains,overspeed and overwind controls,automatic stop controls, and otherfacilities.

(2) At least once each week, the hoistshall be run through one complete cycleof operation to determine that it isoperating properly.

(d) A person trained to operate themechanical escape facility always shallbe available while anyone isunderground to provide the mechanicalescape facilities, if required, to thebottom of each shaft and slope openingthat is part of an escapeway within 30minutes after personnel on the surfacehave been notified of an emergencyrequiring evacuation. However, nooperator is required for automaticallyoperated cages, platforms, or elevators.

(e) Mechanical escape facilities shallhave rated capacities consistent with theloads handled.

(f) Manually-operated mechanicalescape facilities shall be equipped withindicators that accurately and reliablyshow the position of the facility.

(g) Certification. The person makingthe examination as required byparagraph (c) of this section shall certifyby initials, date, and the time that theexamination was made. Certificationsshall be made at or near the facilityexamined.

§ 75.383 Escapeway maps and drills.(a) A map shall be posted or readily

accessible to all miners in each workingsection, and in each area wheremechanized mining equipment is beinginstalled or removed. The map shallshow the designated escapeways fromthe working section to the locationwhere miners must travel to satisfy theescapeway drill specified in paragraph(b)(1) of this section. A map showing themain escapeways shall be posted at asurface location of the mine whereminers congregate, such as at the minebulletin board, bathhouse, or waitingroom. All maps shall be kept up to date,and any changes in route of travel,

locations of doors, or directions ofairflow shall be shown on the maps bythe end of the shift on which thechanges are made, and affected minersshall be informed of the changes beforeentering the underground areas of themine. Miners underground on a shiftwhen any such change is made shall beimmediately notified of the change.

(b) (1) At least once every 90 days,each miner, including miners withworking stations located betweenworking sections and main escapeways,shall participate in a practice escapewaydrill. During this drill, each miner shalltravel the primary or alternateescapeway from the miner’s workingsection or area where mechanizedmining equipment is being installed orremoved, to the area where the split ofair ventilating the working sectionintersects a main air course, or 2,000feet outby the section loading point,whichever distance is greater. Otherminers shall participate in theescapeway drill by traveling in theprimary or alternate escapeway for adistance of 2,000 feet from their workingstation toward the nearest escapefacility or drift opening. An escapewaydrill shall not be conducted in the sameescapeway as the immediatelypreceding drill.

(2) At least once every 6 weeks andfor each shift, at least two miners oneach coal producing working sectionwho work on that section, accompaniedby the section supervisor, shallparticipate in a practice escape drill andshall travel the primary or alternateescapeway from the location specifiedin paragraph (b)(1) of this section, to thesurface, to mechanical escape facilities,or to an underground entrance to a shaftor slope to the surface. Systematicrotation of section personnel shall beused so that all miners participate inthis drill. An escapeway drill shall notbe conducted in the same escapeway asthe immediately preceding drill.

(3) At least once every 6 weeks, atleast two miners on each maintenanceshift and a supervisor, shall participatein a practice escape drill and shall travelthe primary or alternate escapeway fromthe location specified in paragraph(b)(1) of this section, to the surface, tomechanical escape facilities, or to anunderground entrance to a shaft or slopeto the surface. Systematic rotation ofmaintenance personnel and workingsections shall be used so that all minersparticipate in this drill and theescapeways from all sections aretraveled. An escapeway drill shall notbe conducted in the same escapeway asthe immediately preceding drill.

(4) Before or during practiceescapeway drills, miners shall be

informed of the locations of fire doors,check curtains, changes in the routes oftravel, and plans for diverting smokefrom escapeways.

(c) The practice escapeway drills maybe used to satisfy the evacuationspecifications of the fire drills requiredby § 75.1101–23.

§ 75.384 Longwall and shortwalltravelways.

(a) If longwall or shortwall miningsystems are used and the two designatedescapeways required by § 75.380 arelocated on the headgate side of thelongwall or shortwall, a travelway shallbe provided on the tailgate side of thatlongwall or shortwall. The travelwayshall be located to follow the mostdirect and safe practical route to adesignated escapeway.

(b) The route of travel shall be clearlymarked.

(c) When a roof fall or other blockageoccurs that prevents travel in thetravelway—

(1) Work shall cease on the longwallor shortwall face;

(2) Miners shall be withdrawn fromface areas to a safe area outby thesection loading point; and

(3) MSHA shall be notified.(d) Work may resume on the longwall

or shortwall face after the procedures setout in §§ 75.215 and 75.222 areimplemented.

§ 75.385 Opening new mines.

When new mines are opened, no morethan 20 miners at a time shall beallowed in any mine until a connectionhas been made between the mineopenings, and these connections shallbe made as soon as possible.

§ 75.386 Final mining of pillars.

When only one mine opening isavailable due to final mining of pillars,no more than 20 miners at a time shallbe allowed in the mine, and the distancebetween the mine opening and workingface shall not exceed 500 feet.

§ 75.388 Boreholes in advance of mining.

(a) Boreholes shall be drilled in eachadvancing working place when theworking place approaches—

(1) To within 50 feet of any arealocated in the mine as shown by surveysthat are certified by a registeredengineer or registered surveyor unlessthe area has been preshift examined;

(2) To within 200 feet of any arealocated in the mine not shown bysurveys that are certified by a registeredengineer or registered surveyor unlessthe area has been preshift examined; or

(3) To within 200 feet of any mineworkings of an adjacent mine located in


the same coalbed unless the mineworkings have been preshift examined.

(b) Boreholes shall be drilled asfollows:

(1) Into the working face, parallel tothe rib, and within 3 feet of each rib.

(2) Into the working face, parallel tothe rib, and at intervals across the facenot to exceed 8 feet.

(3) At least 20 feet in depth inadvance of the working face, and alwaysmaintained to a distance of 10 feet inadvance of the working face.

(c) Boreholes shall be drilled in bothribs of advancing working placesdescribed in paragraph (a) of thissection unless an alternative drillingplan is approved by the DistrictManager in accordance with paragraph(g) of this section. These boreholes shallbe drilled—

(1) At an angle of 45 degrees to thedirection of advance;

(2) At least 20 feet in depth; and(3) At intervals not to exceed 8 feet.(d) When a borehole penetrates an

area that cannot be examined, andbefore mining continues, a certifiedperson shall, if possible, determine—

(1) The direction of airflow in theborehole;

(2) The pressure differential betweenthe penetrated area and the mineworkings;

(3) The concentrations of methane,oxygen, carbon monoxide, and carbondioxide; and

(4) Whether water is impoundedwithin the penetrated area.

(e) Unless action is taken to dewateror to ventilate penetrated areas,

boreholes shall be plugged with woodenplugs or similar devices when—

(1) Tests conducted at the boreholesshow that the atmosphere in thepenetrated area contains more than 1.0percent methane, less than 19.5 percentoxygen, or harmful concentrations ofcarbon monoxide, carbon dioxide orother explosive, harmful or noxiousgases;

(2) Tests for methane, oxygen, carbonmonoxide, and carbon dioxide cannotbe made because air from mineworkings is flowing into the penetratedarea; or

(3) Water is discharging through theboreholes from the penetrated area intothe mine workings.

(f) If mining is to be conducted within50 feet above or below an inaccessiblearea of another mine, boreholes shall bedrilled, as necessary, according to a planapproved by the district manager.

(g) Alternative borehole patterns thatprovide the same protection to minersas the pattern established by paragraphs(b) and (c) of this section may be usedunder a plan approved by the districtmanager.

§ 75.389 Mining into inaccessible areas.

(a) (1) The operator shall develop andfollow a plan for mining into areaspenetrated by boreholes drilled under§ 75.388.

(2) Mining shall not resume into anyarea penetrated by boreholes untilconditions in the penetrated area can bedetermined under § 75.388 and the plan

for mining-through into the area hasbeen approved by the district manager.

(3) A copy of the procedures to befollowed shall be posted near the site ofthe mining-through operations and theoperator shall explain these proceduresto all miners involved in the operations.

(b) The procedures specified in theplan shall include—

(1) The method of ventilation,ventilation controls, and the airquantities and velocities in the affectedworking section and working place;

(2) Dewatering procedures to be usedif a penetrated area contains a wateraccumulation; and

(3) The procedures and precautions tobe followed during mining-throughoperations.

(c) Except for routine mining-throughoperations that are part of a retreatsection ventilation system approved inaccordance with § 75.371(f) and (x), thefollowing provisions shall apply:

(1) Before and during mining-throughoperations, a certified person shallperform air quality tests at intervals andat locations necessary to protect thesafety of the miners.

(2) During mining-through operations,only persons involved in theseoperations shall be permitted in themine; and

(3) After mining-through, a certifiedperson shall determine that the affectedareas are safe before any persons enterthe underground areas of the mine.

[FR Doc. 96–5453 Filed 3–6–96; 11:23 am]BILLING CODE 4510–43–P

federal register - United States Department of Labor · Mine Ventilation; Final Rule. 9764 Federal Register/Vol. 61, No. 48/Monday, March 11, 1996/Rules and Regulations DEPARTMENT

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