751 Study Guide

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OSHAcademy Course751StudyGuide

Copyright20002014GeigleSafetyGroup,Inc. Page1of85

HearingConservation

ProgramManagement


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OSHAcademyCourse751StudyGuide

HearingConservationProgram

Copyright2014GeigleSafetyGroup,Inc.

Noportionofthistextmaybereprintedforotherthanpersonaluse.Anycommercialuseof

thisdocumentisstrictlyforbidden.ContactOSHAcademytoarrangeforuseasatraining

document.

Thisstudyguideisdesignedtobereviewedofflineasatoolforpreparationtosuccessfully

completeOSHAcademyCourse751.

Readeachmodule,answerthequizquestions,andsubmitthequizquestionsonlinethrough

thecoursewebpage.Youcanprintthepostquizresponsescreenwhichwillcontainthecorrect

answerstothequestions.

Thefinalexamwillconsistofquestionsdevelopedfromthecoursecontentandmodulequizzes.

Wehopeyouenjoythecourseandifyouhaveanyquestions,feelfreetoemailorcall:

OSHAcademy

1915NWAmberglenParkway,Suite400

Beaverton,Oregon97006

www.oshatrain.org

[email protected]

+1.888.668.9079

Disclaimer

This document does not constitute legal advice. Consult with your own company counsel for advice on compliance with all applicable state and

federal regulations. Neither Geigle Safety Group, Inc., nor any of its employees, subcontractors, consultants, committees, or other assignees makeany warranty or representation, either express or implied, with respect to the accuracy, completeness, or usefulness of the information contained

herein, or assume any liability or responsibility for any use, or the results of such use, of any information or process disclosed in this publication.

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LIMITATION, ANY WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Taking actions suggestedin these documents does not guarantee that an operator or contractor will be in compliance with SEMS. Ultimately every company is responsible

for determining the applicability of each section of SEMS to its own operations. Each operators SEMS plan will be different. Mapping safety

and environmental management policies, procedures, or operations using this document does not guarantee compliance with an operators SEMS

plan.


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TableofContents

CourseIntroduction........................................................................................................................ 7

MillionsAreExposedtoHazardousLevelsofNoiseEachDay...............................................7

HighRiskIndustries................................................................................................................ 7

Whatsthestandard?.............................................................................................................. 8

HearingConservationProgram............................................................................................... 8

Module1:Thebasics...................................................................................................................... 9

SoundandNoiseWhatsthedifference?............................................................................ 9

Howissoundmeasured?........................................................................................................ 9

Howdoestheearwork?......................................................................................................... 9

ThePerilsofExposure........................................................................................................... 10

Exposuretochemicals.......................................................................................................... 11

Howdoessounddamagehearing?....................................................................................... 11

Howtoknowifyourhearingisdamaged............................................................................. 11

Module1Quiz........................................................................................................................... 13

MODULE2:EvaluatingExposures................................................................................................. 14

WarningSignsofHazardousWorkplaceNoise..................................................................... 14

HowtoevaluateNoiseexposure?........................................................................................ 14

IndicationsofaProblem....................................................................................................... 14

Walkaroundsurvey.............................................................................................................. 15

WorkshiftSampling............................................................................................................. 15

NoiseSurveyInstruments..................................................................................................... 16

Module2Quiz........................................................................................................................... 18

Module3:ReducingNoiseRelatedHazards................................................................................. 19

Introduction.......................................................................................................................... 19

EngineeringandAdministrativeControls............................................................................. 19

Engineeringcontrols............................................................................................................. 19

ExamplesofEngineeringControls........................................................................................ 20

AdministrativeControls........................................................................................................ 21


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ManagementResponsibilities............................................................................................... 22

EmployeeResponsibilities.................................................................................................... 22

Module3Quiz........................................................................................................................... 24

Module4:HearingConservationPrograms................................................................................. 25

Introduction.......................................................................................................................... 25

Whatconstitutesaneffectivehearingconservationprogram?...........................................25

ProgramElements................................................................................................................. 25

MonitoringProgram............................................................................................................. 25

ProvidingHearingProtectionDevices(HPDs) ManagementResponsibilities..................26

HearingProtectionDevices(HPDs)BasicRequirements..................................................27

HPDSelectionandUse.......................................................................................................... 27

FittingHPDs.......................................................................................................................... 28

HPDAttenuation................................................................................................................... 28

HearingProtectionLabeling................................................................................................. 29

EmployeeTrainingandEducation........................................................................................ 30

AccesstoInformationandTrainingMaterials...................................................................... 31

Module4Quiz........................................................................................................................... 32

Module5: HearingConservationProgramBenefits.................................................................... 34

Introduction.......................................................................................................................... 34

TheCosts............................................................................................................................... 34

EmployerBenefits................................................................................................................. 34

EmployeeBenefits................................................................................................................ 35

Module5Quiz........................................................................................................................... 37

Module6: HearingConservation:RequiredMonitoring.............................................................39

Whenmusttheemployerrepeatmonitoring?.................................................................... 39

Whatisaudiometrictesting?................................................................................................ 39

Whatisabaselineaudiogram?............................................................................................. 40

Whatareannualaudiograms?.............................................................................................. 40

Whatisanemployerrequiredtodofollowinganaudiogramevaluation?.........................41


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Whenshouldanemployerperformanaudiogram?............................................................41

Whenareemployeesrequiredtowearhearingprotectors?...............................................42

NoiseReductionRatings(NRR)............................................................................................. 42

StandardThresholdShift(STS)............................................................................................. 42

WhatTrainingisrequired?................................................................................................... 42

Whatexposureandtestingrecordsmustemployerskeep?................................................43


Module6Quiz........................................................................................................................... 44

Module7:HearingConservationProgramAudit(Optional)........................................................46

Introduction.......................................................................................................................... 46

Programevaluationchecklist,canservewell...................................................................... 46

Howdoessafetyandhealthmanagementsystemassistancehelpemployersand

employees?........................................................................................................................... 48

HearingConservationProgramEvaluationChecklist...........................................................49

EngineeringandAdministrativeControls............................................................................. 50

HearingProtectionDevices................................................................................................... 52

Module7Quiz........................................................................................................................... 54

Module8:PolicyNeeds(Optional)............................................................................................... 56

PoliciesManagementMustAddress.................................................................................... 56

Settinguptrainingsessions.................................................................................................. 58

ProgramImplementerResponsibilities................................................................................ 59

RewardsandPunishments.................................................................................................... 61

RecordKeeping..................................................................................................................... 62


Module8Quiz........................................................................................................................... 66

Module9:TheFutureofHearingLossPrevention(Optional).....................................................68

Introduction.......................................................................................................................... 68

HolisticApproach:LookingatFactorsOtherThanNoise.....................................................68

TaskBasedExposureAssessment........................................................................................ 69


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NewDirectionsinTheoriesaboutSelfProtectiveBehavior................................................71

Module9Quiz........................................................................................................................... 73

AppendixA.................................................................................................................................... 74

SoundLevelMeter ConsiderationsforUse............................................................................ 74

MeasuringImpulse/ImpactSounds.......................................................................................... 74

ANSIStandards.......................................................................................................................... 74

AppendixB.................................................................................................................................... 76

Dosimeter ConsiderationsforUse.......................................................................................... 76

Settings...................................................................................................................................... 76

DosimeterReadout................................................................................................................... 77

AmericanNationalStandardsInstitute(ANSI)Standards........................................................78

Glossary......................................................................................................................................... 80

Endnotes....................................................................................................................................... 85


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CourseIntroduction

MillionsAreExposedtoHazardousLevelsofNoiseEachDay

IntheUnitedStates,fourmillionworkersgotoworkeachdayindamagingnoise.Tenmillion

peoplehaveanoiserelatedhearingloss.Occupationalhearinglossisthemostcommonwork

relatedillnessintheUnitedStates. Approximately22millionU.S.workersexposedto

hazardousnoiselevelsatwork,andanadditional9millionexposedtoototoxicchemicals.An

estimated$242millionisspentannuallyonworkerscompensationforhearinglossdisability.

In2007,approximately23,000caseswerereportedofoccupationalhearinglossthatwasgreat

enoughtocausehearingimpairment. In2008,approximately2millionU.S.workerswere

exposedtonoiselevelsatworkthatputthematriskofhearingloss. In2007,approximately

82%ofthecasesinvolvingoccupationalhearinglosswerereportedamongworkersinthe

manufacturingsector. Noiserelatedhearinglosshasbeenlistedasoneofthemostprevalent

occupationalhealthconcernsintheUnitedStatesformorethan25years.Thousandsof

workerseveryyearsufferfrompreventablehearinglossduetohighworkplacenoiselevels.

HighRiskIndustries

Whileanyworkercanbeatriskfornoiseinducedhearinglossintheworkplace,workersin

manyindustrieshavehigherexposurestodangerouslevelsofnoise.Industrieswithhigh

numbersofexposedworkersinclude:agriculture;mining;construction;manufacturingand

utilities;transportation;andmilitary.

Noiseinduced

hearing

loss

is

one

of

the

most

common

occupational

disease

and

the

second

mostselfreportedoccupationalillnessorinjury.Industryspecificstudiesreveal:

44%ofcarpentersand48%ofplumbersreportedthattheyhadaperceivedhearingloss.

49%ofmale,metal/nonmetalminers,willhaveahearingimpairmentbyage50(vs.9%

ofthegeneralpopulation)risingto70%byage60.

Whileanyworkercanbeatriskfornoise

inducedhearinglossintheworkplace,workers

inmanyindustrieshavehigherexposuresto

dangerouslevelsofnoise.Industrieswithhigh

numbersofexposedworkersinclude:

agriculture;mining;construction;

manufacturingandutilities;transportation;and

military.


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Whatsthestandard?

OSHAsetslegallimits,indecibels,onnoiseexposureintheworkplace. Adecibelistheunit

usedtomeasuretheintensityofasoundandwelltalkmoreaboutthislaterinthecourse.

Theselimitsarebasedontheaverageamountoftimeaworkersisexposedtonoiseoveran8

hourday(calledatimeweightedaverage). Itsimportantthatyourefamiliarwithtwo

importantnoiselevellimitsintheworkplace:

1. OSHA'spermissibleexposurelimit(PEL)is90dBAforallworkersforan8hourday.2. OSHArequiresemployerstoimplementaHearingConservationProgramwhereworkersare

exposedtoatimeweightedaveragenoiselevelof85dBAorhigheroveran8hourworkshift.

HearingConservationProgram

OSHAshearingconservationprogramisdesignedtoprotectworkerswithsignificant

occupationalnoiseexposuresfromhearingimpairmenteveniftheyaresubjecttosuchnoise

exposuresovertheirentireworkinglifetimes.

HearingConservationProgramsrequireemployersto:

measurenoiselevels,

providefreeannualhearingexamsandfreehearingprotection,

providetraining,and

conductevaluationsoftheadequacyofthehearingprotectorsinuseunlesschangesto

tools,equipmentandschedulesaremadesothattheyarelessnoisy,andworker

exposuretonoiseislessthanthetimeweightedaverageof85dBAoveran8hourwork

shift.

ThiscoursesummarizestherequiredcomponentofOSHAshearingconservationprogramfor

generalindustry.Itcoversmonitoring,audiometrictesting,hearingprotectors,training,and

recordkeepingrequirements.


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Module1:Thebasics

SoundandNoiseWhatsthedifference?

Sound consistsofpressurechangesina

medium(usuallyair),causedbyvibration

orturbulence.

These

pressure

changes

producewavesemanatingawayfromthe

turbulentorvibratingsource.

Noise isnothingmorethanunwanted

sound. Noiseisoneofthemost

widespreadoccupationalhealthproblems.

Itisabyproductofmanyindustrialprocesses.

Howissoundmeasured?

Soundis

measured

in

two

ways:

decibels

and

frequency.

Decibelsmeasurethepressureofsound.Frequencyisrelatedtoasoundspitchandis

measuredinunitscalledhertz(Hz),orcyclespersecond.Thepitchofasoundhowhighor

lowitseemsishowyouperceiveitsfrequency;thehigherthepitch,thehigherthe

frequency.Highfrequencysoundsaregenerallymoreannoyingthanlowfrequencysoundsand

canbemoreharmfultohearing.

Humanhearingismostsensitivetofrequenciesbetween3,000and4,000Hz.Thatswhypeople

withdamagedhearinghavedifficultyunderstandinghigherpitchedvoicesandothersoundsin

the3,000

to

4,000

Hz

range.

CheckouttheCDCNoiseMeterpagetogetabetterideahowloudisloud.

Howdoestheearwork?

Whensoundwavesentertheouterear,thevibrationsimpacttheeardrumandaretransmitted

tothemiddleandinnerear.

Inthemiddleearthreesmallbonescalledthemalleus(orhammer),theincus(oranvil),andthe

stapes(orstirrup)amplifyandtransmitthevibrationsgeneratedbythesoundtotheinnerear.

Theinner

ear

contains

asnail

like

structure

called

the

cochlea

which

is

filled

with

fluid

and

lined

withcellswithveryfinehairs.Thesemicroscopichairsmovewiththevibrationsandconvert

thesoundwavesintonerveimpulsestheresultisthesoundwehear. Exposuretoloudnoise

candestroythesehaircellsandcausehearingloss!


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ThePerilsofExposure

Exposuretonoiseismeasuredinunitsofsoundpressurelevelscalleddecibels,namedafter

AlexanderGrahamBell,usingAweightedsoundlevels(dBA).TheAweightedsoundlevels

closelymatchtheperceptionofloudnessbythehumanear.

Exposuretohighlevelsofnoisecauseshearinglossandmaycauseotherharmfulhealtheffects

aswell.Theextentofdamagemostlydependsontheintensityofthenoiseandthedurationof

theexposure.

Hearing

loss

caused

by

noise

can

be

temporary

or

permanent.

Temporaryhearinglossresultsfromshorttermexposurestonoise,withnormalhearing

returningafteraperiodofrest.

Prolongedexposuretohighnoiselevelsoveraperiodoftimegraduallycauses

permanentdamage.

Loudnoisecanalsocreatephysicalandpsychologicalstress,reduceproductivity,interferewith

communicationandconcentration,andcontributetoworkplaceaccidentsandinjuriesby

makingitdifficulttohearwarningsignals.

Noiseinducedhearinglosslimitsyourabilitytohearhighfrequencysounds,understand

speech,andseriouslyimpairsyourabilitytocommunicate.


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Theeffectsofhearinglosscanbeprofoundashearinglosscaninterferewithyourabilityto

enjoysocializingwithfriends,playingwithyourchildrenorgrandchildren,orparticipatingin

othersocialactivitiesyouenjoy,andcanleadtopsychologicalandsocialisolation.

Exposuretochemicals

Nolonger

is

noise

considered

to

be

the

only

source

of

hearing

loss

associated

with

work.

Exposuretochemicals,suchasaromaticsolventsandmetalssuchaslead,arsenic,andmercury

canresultinhearingloss.

Combinedexposurestonoiseandchemicalscancausemorehearinglossthanexposureto

eitheragentalone.Vibrationandextremeheatarealsopotentiallyharmfultohearingwhen

combinedwithnoise.

Howdoessounddamagehearing?

Very

loud

sounds

can

damage

the

sensitive

hair

cells

in

your

inner

ear.

Hair

cells

are

the

foot

soldiersforyourhearing.Asthenumberofdamagedhaircellsincreases,yourbrainreceives

fewerimpulsestointerpretassound.Whenyoudamagehaircells,youdamagehearing.

Whileasingleexposuretoloudnoisecandamageyourhaircells,itprobablywontdestroy

them.Youmayexperienceringinginyourearsandsomesoundsmaybemuffled,butyourhair

cellswillrecoverandsowillyourhearing.Thisiscalledatemporarythresholdshift.But

repeatedexposurestoloudnoisecandamagehaircellstothepointthattheywontrecover.

Becausethedamageispermanent,theresultiscalledapermanentthresholdshift.No

treatmentwillrestoreit.Whenyoudestroyhaircells,youdestroyhearing.

Howtoknowifyourhearingisdamaged

Hearinglossispainlessandgradual.Itusuallydevelopsoverseveralyearsyoumightnot

evennoticethelossduringthoseyears.


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Sometimes,overexposuretoloudnoisecantriggerringingorothersoundsinyourears,called

Tinnitus.Whiletinnitusmaybeasymptomofdamagedhearing,itcanalsobecausedby

infections,medications,andearwax.

Theonlywaytoknowforsureifnoisehasdamagedyourhearingistohaveahearing

examinationbyacertifiedaudiometrictechnician,audiologist,otolaryngologist,orphysician.

Ifyouansweryestoanyofthefollowingquestions,yourhearingmaybeatrisk:

Doyoufrequentlyaskpeopletorepeatsentences?

Doyoufeelyourhearingisnotasgoodasitwas10yearsago?

Havefamilymembersnoticedaproblemwithyourhearing?

Areyouexposedtoloudnoisewithouthearingprotectionwhereyouwork?

Doyouhavetoshouttoacoworkerbecauseofthenoisearoundyou?

Areyou

exposed

to

noise

from

firearms,

motorcycles,

snowmobiles,

power

tools,

or

loudmusicwithouthearingprotection?

Congratulations! Yourefinishedwiththefirstmodule. Dontforgettoreviewthequiz.


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Module1Quiz

Usethisquiztoselfcheckyourunderstandingofthemodulecontent.Youcanalsogoonline

andtakethisquizwithinthemodule.Theonlinequizprovidesthecorrectansweronce

submitted.

1.

Soundconsists

of

pressure

changes

in

amedium

(usually

air),

caused

by

_____

or_____.

a. vibration,turbulence

b.

turbulence,noise

c. vibration,noise

d. Bothaandb

2.

Whatisnoise?

a.

Pressurechanges

b. Unwantedsound

c.

Decibels

d. Varyingfrequencies

3.

Betweenwhichfrequenciesishumanhearingmostsensitiveto?

a. 1,000and5,000Hz

b. 3,000and8,000Hz

c. 1,000and2,000Hz

d.

3,000and4,000Hz

4.

Whatarethetwofactorsthatdeterminetheamountofhearinglossaperson

experienceswhenexposedtoloudnoises?

a. Decibelsandfrequency

b.

dBAandAweightedsoundlevels

c. Intensityandduration

d. Soundandnoise

5.

Sometimes,

overexposure

to

loud

noise

can

trigger

ringing

or

other

sounds

in

yourears,called_____.

a. Audiotis

b. Ringitis

c. Frunitus

d.

Tinnitus


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Module2:EvaluatingExposures

WarningSignsofHazardousWorkplaceNoise

Noisemaybeaprobleminyourworkplaceif:

Youhear

ringing

or

humming

in

your

ears

when

youleavework.

Youhavetoshouttobeheardbyacoworkeran

arm'slengthaway.

Youexperiencetemporaryhearinglosswhen

leavingwork.

Noiseinducedhearinglosscandeveloprapidlyinworkers

exposedto

relatively

high

noise

levels

on

adaily

basis.

HowtoevaluateNoiseexposure?

Thefirststeptowardsolvinganynoiseproblemisto

defineit.Tounderstandwhatrequirementsmustbe

implementedaccordingtoOSHA'snoisestandard,itis

necessarytodetermineexposurelevels.Thefollowing

sectionsprovideinformationaboutevaluatingnoise

exposurelevels:

IndicationsofaProblem

WalkaroundSurvey

WorkshiftSampling

InstrumentsUsedtoConductaNoiseSurvey

IndicationsofaProblem

Therearevariousfactorsthatmayindicatenoiseisaproblemintheworkplace.Whilepeople

reactdifferentlytonoise,subjectiveresponsesshouldnotbeignoredbecausetheymay

providewarnings

that

noise

may

be

at

unacceptable

levels.

Noisyconditionscanmakenormalconversationdifficult.

Whennoiselevelsareabove80decibels(dB),peoplehavetospeakveryloudly.

Whennoiselevelsarebetween85and90dB,peoplehavetoshout.


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Whennoiselevelsaregreaterthan95dB,peoplehavetomoveclosetogethertoheareach

otheratall.

Walkaroundsurvey

Awalkaroundsurveyshouldbeperformedtoscreenfornoiseexposuresandtodetermineif

additionalmonitoring

is

necessary.

When

screening

for

noise

exposures,

sound

level

meter

measurementsandestimatesofthedurationofexposurearesufficient.Theresultingspot

readingscanbeusedtodeterminetheneedforamorethoroughevaluation.Thefollowing

generalapproachmaybefollowed:

1. Tourthefacilityanddevelopadetailedunderstandingoffacilityoperationsand

potentialnoisesources.Makenotesonadiagramofthefloorplanifpossible.Lookfor

indicationsthatnoisemaybeaproblem.

2.

Useasoundlevelmetertotakespotreadingsofoperationsthatareinquestion.Itmay

beuseful

to

mark

the

sound

levels

on

adiagram

of

the

floor

plan.

Make

notes

regarding

whatequipmentisonoroff.

3. Estimateexposuresbyidentifyingworkersandtheirlocations,andestimatethelength

oftimetheyspendindifferentareasorhowlongtheyoperateparticularequipmentor

tools.

Iftheresultsofthewalkaroundsurveyindicatetimeweightedaverage(TWA)exposuresof80

dBAormore,thenadditionalnoisemonitoringshouldbeperformed.

WorkshiftSampling

Whenthe

results

of

the

walk

around

survey

indicate

that

the

noise

levels

may

exceed

those

outlinedinOSHA'snoisestandard,additionalmonitoringisnecessary.Establishasampling

protocolforyourworkplace.Ageneralprotocolisprovidedasanexample.

Followthissamplingprotocol:

1. Informtheemployeebeingmonitoredthatthedosimeter(noisesamplingequipment)

shouldnotinterferewithhis/hernormalduties,andemphasizethattheemployee

shouldcontinuetoworkasusual.

2. Explainthepurposeofthedosimetertoeachemployeebeingsampledandemphasize

thatthe

dosimeter

is

not

aspeech

recording

device.

3. Instructtheemployeebeingsamplednottoremovethedosimeterunlessabsolutely

necessaryandnottocoverthemicrophonewithacoatoroutergarmentormoveit

fromitsinstalledposition.Informtheemployeewhenandwherethedosimeterwillbe

removed.


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4. Themicrophoneshouldbelocatedintheemployee'shearingzone.OSHAdefinesthe

hearingzoneasaspherewithatwofootdiametersurroundingthehead.Clipthe

microphonetotheemployee'sclothingaccordingtothemanufacturer'sinstructions.

Mostmanufacturersrecommendthatthemicrophonebeplacedontheshoulderarea

midwaybetweentheheadandthepointoftheshoulder.Practicalityandsafetywill

dictatetheactualmicrophoneplacementateachsurveylocation.

5. Usethemicrophonewindscreentoprotectthemicrophonewhentheweareris

outdoorsorindustyordirtyareas(thewindscreenwillnotprotectthemicrophone

fromrainorextremehumidity).

6.

Whennoiselevelsaredifferentateachoftheemployeesears,thehigherlevelmustbe

sampled.

7.

Positionandsecureanyexcessmicrophonecabletoavoidsnaggingorinconvenienceto

theemployee.Ifpractical,thecordshouldberunundertheemployee'sshirtorcoat.

8. Checkthedosimeterperiodicallytoensurethemicrophoneisproperlyoriented.

9. Obtainandnotesoundlevelmeterreadingsduringdifferentphasesofworkthe

employeeperformsduringtheshift.Thereisnominimumregardingthenumberof

readingstoobtain,butitisimportanttotakeenoughreadingstoidentifyworkcycles.

Forstatisticalreasons,morereadingsshouldbetakenwhennoiselevelsfluctuate

widely.

10.RecordtheinformationrequiredontheOSHA92NoiseSurveyReport.

NoiseSurveyInstruments

Sound

Level

Meter

Therearevariousfactorsthatmayindicatenoiseisaproblemintheworkplace.Whilepeople

reactdifferentlytonoise,subjectiveresponsesshouldnotbeignoredbecausetheymay

providewarningsthatnoisemaybeatunacceptablelevels.Asoundlevelmeter(SLM)isthe

basicinstrumentforinvestigatingnoiselevels.

Forcompliancepurposes,readingswithanANSIType2soundlevelmeteranddosimeterare

consideredtohaveanaccuracyof2dBAwhileaType1instrumenthasanaccuracyof1dBA.


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Soundlevelmeterscanbeusedto:

Spotchecknoisedosimeterperformance.

Determinetheemployee'snoisedosewheneveruseofanoise

dosimeterisunavailableorinappropriate.

Identifyand

evaluate

individual

noise

sources

for

abatement

purposes.

Aidindeterminingthefeasibilityofengineeringcontrolsforindividual

noisesources.

Evaluatehearingprotectors.

PleaserefertoAppendixAifyouwouldliketolearnmoreaboutthe

considerationsofuseforsoundlevelmeters.

Dosimeter

Likeasound

level

meter,

anoise

dosimeter

can

also

measure

sound

levels.However,thedosimeterisactuallywornbytheemployeein

ordertodeterminethepersonalnoisedoseduringtheworkshiftor

samplingperiod. AccordingtoOSHA'snoisestandard,thenoisedosimeteristheprimary

instrumentformakingcompliancemeasurements.

Dosimeterscanbeusedto:

MakecompliancemeasurementsaccordingtoOSHA'snoisestandard.

Measure

the

employee's

exposure

to

noise

and

automatically

compute

the

necessary

noisedosecalculations.

PleaserefertoAppendixBifyouwouldliketolearnmoreabouttheconsiderationsofusefor

adosimeter.

Employees

Wearing

Headsets

are

at

Risk

Noiseoverexposureintheworkplacecanoccurwhereemployeeswearacommunications

headsetaspartoftheiremployment.Clericalpersonnel,aircraftpilotsandothercockpit

personnel,airtrafficcontrollers,emergencypersonnel,reservationclerks,receptionists,and

telephoneoperators

are

just

afew

examples

of

the

more

than

three

million

workers

who

can

beexposedtohighnoiselevelsviacommunication'sheadsets.

Goodjob! Anothermoduledownandsevenmoretogo


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Module2Quiz



submitted.

1.

Thefirst

step

toward

solving

any

noise

problem

is

to

_____

it.

a. Define

b. Neglect

c. Ignore

d. Avoid

2.

ANSIType2metershaveanaccuracyof_____.

a.

1dBA

b. 2dBA

c.

3dBA

d.

4dBA

3.

AccordingtoOSHAsnoisestandard29CFR1910.95,the_____istheprimary

instrumentformakingcompliancemeasurements.

a. Noisedosimeter

b. AcousticLimitedDevices

c. OctaveBandAnalyzers

d. AudioEqualizer

4.

Canoverexposuretonoiseintheworkplaceoccurwhereemployeesweara

communicationsheadset?

a. Yes

b.

No

5.

Whenmaynoisebeaprobleminyourworkplace?

a. Youhearringingorhumminginyourearswhenyouleavework.

b.

Youhavetoshouttobeheardbyacoworkeranarm'slengthaway.

c. Youexperiencetemporaryhearinglosswhenleavingwork.

d.

Alloftheabove


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Module3:ReducingNoiseRelatedHazards

Introduction

Noisecontrolstrategiesarethefirstlineofdefenseagainstexcessivenoiseexposure.Theuse

ofthesecontrolsshouldaimtoreducethehazardousexposuretothepointwheretheriskto

hearingis

eliminated

or

minimized.

With

the

reduction

of

even

afew

decibels,

the

hazard

to

hearingisreduced,communicationisimproved,andnoiserelatedannoyanceisreduced.There

areseveralwaystocontrolandreduceworkerexposuretonoiseintheworkplace.

EngineeringandAdministrativeControls

Engineeringandadministrativecontrolstrategiesareessentialtoachievinganeffective

hearingconservationandhearingconservationprogram.Engineeringandadministrative

controlsrepresentthefirsttwoprimarystrategiesintheHierarchyofControls:

1.

removethe

hazard

through

engineering

strategies,

and

2.

removetheexposurethroughadministrativestrategies.

Theuseofthesecontrolsshouldreducehazardousexposuretothepointwheretheriskto

hearingiseliminatedoratleastmoremanageable.

Engineeringcontrols

Engineeringcontrolsthatreducesoundexposurelevelsareavailableandtechnologically

feasibleformostnoisesources.Engineeringcontrolsinvolvemodifyingorreplacingequipment,

ormaking

related

physical

changes

at

the

noise

source

or

along

the

transmission

path

to

reduce

thenoiselevelattheworker'sear.Insomeinstances,theapplicationofarelativelysimple

engineeringnoisecontrolsolutionreducesthenoisehazardtotheextentthatfurther

requirementsoftheOSHANoisestandard(e.g.,audiometrictesting(hearingtests),hearing

conservationprogram,provisionofhearingprotectors,etc)arenotnecessary.Examplesof

inexpensive,effectiveengineeringcontrolsincludesomeofthefollowing:

Chooselownoisetoolsandmachinery(e.g.,BuyQuietRoadmap(NASA)).

Maintainandlubricatemachineryandequipment(e.g.,oilbearings).

Placeabarrierbetweenthenoisesourceandemployee(e.g.,soundwallsorcurtains).

Encloseorisolatethenoisesource.


20/85



Examples

of

Engineering

Controls

Forhearinglosspreventionpurposes,engineeringcontrolsaredefinedasanymodificationor

replacementofequipment,orrelatedphysicalchangeatthenoisesourceoralongthe

transmissionpath(withtheexceptionofhearingprotectors)thatreducesthenoiselevelatthe

employee'sear.

Typicalengineeringcontrolsinvolve:

1.Reducingnoiseatthesource.

2.Interruptingthenoisepath.

3.Reducingreverberation.

4.Reducingstructurebornevibration.

Commonexamplesoftheimplementationofsuchcontrolsare:

1.Installingamuffler.

2.Erectingacousticalenclosuresandbarriers.

3.Installingsoundabsorbingmaterial.

4.Installingvibrationmountsandprovidingproperlubrication.

Assessingtheapplicabilityofengineeringcontrolsisasophisticatedprocess.

First,thenoiseproblemmustbedefined.Thisnecessitatesmeasuringthenoiselevels

anddevelopingcompleteinformationonemployeenoiseexposureandtheneedfor

noisereduction.


21/85



Next,anapproachtoengineeringcontrolmustbedeveloped,requiringthe

identificationofindividualnoisesourcesandassessmentoftheircontributionstothe

overallnoiselevels.

Whenchoosingthemostapplicableengineeringcontrols,youwillneedtoconsiderthecostof

purchasing,operating,servicing,andmaintainingthecontrol.Forthisreason,engineering,

safety,andindustrialhygienepersonnel,aswellasemployeeswhooperate,service,and

maintainequipment,mustbeinvolvedinthenoisecontrolplan.

Employeeswhoworkwiththeequipmentonadailybasiswillbeabletoprovidevaluable

guidanceonsuchimportantmattersasthepositioningofmonitoringindicatorsandpanels,

lubricationandservicingpoints,controlswitches,andtheproperlocationofaccessdoorsfor

operationandmaintenance.

Insituationswhereemployeeswillbeworkingonoraroundequipmentfittedwithengineering

controls,itisimportanttoexplaintoeveryoneinvolvedwhythecontrolsshouldnotbe

modified,removed,orotherwisedefeated.

AdministrativeControls

Administrativecontrolsarechangesintheworkplacethatreduceoreliminateworker

exposuretonoise,examplesinclude:

Operatingnoisymachinesduringshiftswhenfewerpeopleareexposed.

Limitingtheamountoftimeapersonspendsatanoisesource.

Providingquiet

areas

where

workers

can

gain

relief

from

hazardous

noise

sources

(e.g.,

constructasoundproofroomwhereworkers'hearingcanrecoverdependingupon

theirindividualnoiselevelanddurationofexposure,andtimespentinthequietarea).

Restrictingworkerpresencetoasuitable

distanceawayfromnoisyequipment.

Controllingnoiseexposurethroughdistance

isoftenaneffective,yetsimpleand

inexpensiveadministrativecontrol.This

controlmaybeapplicablewhenworkersare

presentbut

are

not

actually

working

with

a

noisesourceorequipment.Increasingthe

distancebetweenthenoisesourceandtheworker,reducestheirexposure.Inopen

space,foreverydoublingofthedistancebetweenthesourceofnoiseandtheworker,

thenoiseisdecreasedby6dBA.


22/85



ManagementResponsibilities

Management'sprimaryresponsibilitiesaretomakesurethatpotentiallycontrollablenoise

sourcesareidentified,andthatprioritiesforcontrolsaresetandaccomplished.Forthis

purpose,managementneedstoallocatetheappropriateresourcesandengageoutsideservices

oridentifycapablepersonnelinhouse.

Itisalsomanagement'sresponsibilitytoseethatanychangesofequipmentorprocessare

doneonlyafterevaluationoftheirimpactonemployeenoiseexposure.

Thepurchaseofquieternewequipmentcanbeveryhelpful,butisusuallyaccomplishedonly

withexplicitspecification,andoccasionallysomepressureontheequipmentmanufacturers.

Sometimesthecompanymustbewillingtopaymoreforquieterequipment,butthese

expendituresshouldbecosteffectiveinthelongrun.

Implementingabuyquietprogramcansignificantlyreducetheamountoftimeittakesfor

workplacenoisetonolongerbehazardous.

Oftenanoisecontroleffortmayseemtobeoverwhelming.Asaresult,thecompanymay

decidethatnoisecontrolisnotfeasibleandinsteadrelyonhearinglosspreventionmeasuresto

preventhearingloss.However,ifnoisesourcesaretakenononeatatime,dealingwiththe

noisiestoreasiesttoquietsourcesfirst,theproblemcanbecomemanageableovertimesothat

hearinglosspreventionmeasureswillbeneededonlyuntilthenoiseisreducedtoasafelevel.

Manytimestwohazardscanbereducedoreliminatedatoncesuchasinthecaseofenclosinga

noisymachinethatgenerateshighheatlevelsaswell.Theenclosurecantrapthenoiseandthe

heatcanbeventedofftotheoutside.

Managersmayneedtocommitresourcesforinhousedevelopmentoftechnologytocontrol

exposureproblemsspecifictotheircompaniesandprocesses.Insomecases,theymayneedto

budgetformaintenanceofexposurecontroldevicestopreventtheirdeteriorationovertime.

Finally,theyshouldmakesurethatlunchandbreakareasareasfreefromnoisehazardsas

reasonablypossible,andthatotheravenuesofadministrativecontrolshavebeenexplored.

EmployeeResponsibilities

Employeeswhooperateormaintainandrepairtheequipmentareoftentheoneswhoknow

mostabouttheprocessesinvolved,theyneedtoexpresstheirconcernsandideasto

management,theprogramimplementer,orthenoisecontrolengineersothatthenoise

controldeviceswillbeaspracticalandeffectiveaspossible.Employeeassistanceisespecially

criticaltothesuccessofengineeringnoisesurveyswheresoundsourceswithinaworkprocess

orapieceofequipmentneedtobeevaluated,andonlytheemployeeknowstheproper


23/85



operationoftheequipment.Employeesalsoneedtocooperatebymaintainingtheirnormal

workroutinewhenaskedtoweardosimeters,sothattheresultswillberepresentativeoftheir

actualexposures.

Soundlevelsoftenincreasewhenequipmentbeginstowearorfailstoreceiveappropriate

maintenance.Also,

changes

in

equipment

placement

may

cause

unintended

effects

on

sound

levels.Whenemployeesnoticesuchchanges,theyneedtoinformthesupervisorypersonnelor

theprogramimplementerthatachangehasoccurred.Aresurveywillbeneededtoevaluate

thenewsoundlevelsandemployeeexposureswheneverequipmentorproductionchanges

occur.

Employeesalsohavetheresponsibilityoflearningtooperatetheirmachineswiththenoise

controlsinplace,ofmaintainingthecontrolsproperly,andofnotifyingtheappropriate

personnelwhenadditionalmaintenanceisneeded.

Greatwork! Thatstheendofmodulethree,goodluckonthequiz.


24/85



Module3Quiz



submitted.

1.

Typicalengineering

controls

involve

all

of

the

following

except

_____.

a. reducingnoiseatthesource

b. interruptingthenoisepath

c.

reducingreverberation

d.

redesignoftheequipment

2.

Insituationswhereemployeeswillbeworkingonoraroundequipmentfitted

withengineeringcontrols,itisimportanttoexplaintoeveryoneinvolvedwhy

thecontrolsshouldnotbemodified,removed,orotherwisedefeated?

a.

True

b. False

3.

Whatareadministrativecontrols?

a. Changesintheworkplacethatreplaceequipment.

b. Changesintheworkplacethatincreasetheworkerexposuretonoise.

c.

Changesintheworkplacethatreduceoreliminatetheworkerexposureto

noise.

d.

Changes

in

the

workplace

that

modify

equipment.

4.

WhichofthechoicesbelowareexamplesofAdministrativecontrols?

a. Providequietareasforworkers

b. Restrictworkerstoasuitabledistanceawayfromnoise

c. Interruptingthenoisepath

d. Bothaandb

e. Alloftheabove

5.

_____and_____controlsrepresentthefirsttwoprimarystrategiesinthe

Hierarchyof

Controls.

a. Engineeringandmanagement

b. Engineeringandadministrative

c.

Administrativeandmanagement

d.

Managementandemployee


25/85



Module4:HearingConservationPrograms

Introduction

Hearingconservationprogramsstrivetopreventinitialoccupationalhearingloss,preserveand

protectremaininghearing,andequipworkerswiththeknowledgeandhearingprotection

devicesnecessary

to

safeguard

themselves.

Employers

are

required

to

measure

noise

levels;

providefreeannualhearingexams,hearingprotection,andtraining;andconductevaluations

oftheadequacyofthehearingprotectorsinuse(unlesschangesmadetotools,equipment,

andschedulesresultinworkernoiseexposurelevelsthatarelessthanthe85dBA).Research

indicatesthatworkplaceswithappropriateandeffectivehearingconservationprogramshave

higherlevelsofworkerproductivityandalowerincidenceofabsenteeism.

Whatconstitutesaneffectivehearingconservationprogram?

Aneffectivehearingconservationprogramcanpreventhearingloss,improveemployeemorale

andageneral

feeling

of

well

being,

increase

quality

of

production,

and

reduce

the

incidence

of

stressrelateddisease.

Theemployershouldadministeracontinuing,effectivehearingconservationprogram

wheneveremployeenoiseexposuresareatoraboveaneighthourtimeweightedaverage

(TWA)of85dBAor,equivalently,adoseof50percent.

ProgramElements

AsdetailedinOSHAs1910.95rule,theelementsofaneffectivehearingconservationprogram

are:

MonitoringProgram

AudiometricTestingProgram

HearingProtectionDevices(HPDs)

EmployeeTrainingandEducation

Recordkeeping

Therearealsospecifichearingconservationprogramrequirementsforagricultural,maritime,

andconstructionworksites.

MonitoringProgram

Theemployermustdevelopandimplementamonitoringprogramwheneverinformation

indicatesthatanyemployee'sexposuremayequalorexceedtheactionlevel.

Thesamplingstrategymustbedesignedtoidentifyallemployeesforinclusioninthe

hearingconservationprogram,andenabletheproperselectionofhearingprotectors.


26/85


27/85



Programimplementersshouldalsobegivenresourcesandfacilitiestotrainemployeesinthe

useandcareofhearingprotectors.

Enforcement

Enforcingtheuseofhearingprotectorsismanagement'ssecondvitalresponsibility.

Hearing

Protection

Devices

(HPDs)

Basic

Requirements

Hearingprotectiondevices(HPDs),whichareaformofpersonal

protectionequipment(PPE),areconsideredthelastoptiontocontrol

exposurestonoise.HPDsaregenerallyusedduringthenecessarytimeit

takestoimplementengineeringoradministrativecontrols,orwhensuch

controlsarenotfeasible.

EmployersmustmakeHPDsavailabletoallemployeesexposedatorabovethe

actionlevel.Thesemustbeprovidedatnocosttoemployeesandmustbereplaced

as

necessary.

EmployersmustensurethatHPDsarewornbyemployees:wherefeasible

administrativeandengineeringcontrolsfailtoreducesoundlevelswithinthose

listedinTableG16of29CFR1910.95(i)(2)(ii)(A)andwho

o havenotyethadabaselineaudiogramestablishedor

o haveexperiencedastandardthresholdshift(STS).

HPD

Selection

and

Use

Itisessentialtothesuccessoftheprogramtohavesomeoneresponsiblefortheselectionof

hearingprotection

devices

and

the

supervision

of

their

use.

They

must

be

able

to

evaluate

and

selectappropriatedevicesforeachemployee,basedonproperfit,theemployee'snoise

exposure,hearingability,communicationneeds,personalpreferencesandotherconstraints

imposedbyjobtasksorworkenvironment.

Useofpersonalsafetyequipment,suchashearingprotectors,mustbe

clearlystatedasaconditionofemployment,andmanagementshouldbe

prepared

to

deal

accordingly

with

those

who

violate

the

policy.

Those

who

havedecidednottowearhearingprotectioninnoisyareasalsohave

decidednottoworkforthecompany.


28/85



Noteverypersoncanweareveryhearingprotector.Somepeoplemaybeunabletowear

certaintypesofearplugsbecauseoftheshapeorsizeoftheirearcanals.Becauseofindividual

differencesintheshapesandsizesofheads,somepeoplewillbeunabletowearsome

earmuffs.Individualassessmentofcomfortandabilitytotolerateprolongeduseofagiven

devicecannotbepredictedandwillvarywidelybetweenindividuals.Also,someprotectorsmay

beincompatiblewithdifferingsafetyandprotectivedevices.

Therefore,programimplementersmustmakeavarietyofdevicesavailable.Preferably,

programimplementersshouldmakeavailableasetofdevicesthathavebeenpilottestedfor

effectivenessandemployeeacceptance.

FittingHPDs

Whenfittinghearingprotectors,attentionneedstobegiventoeachear.Itisnotuncommon

forapersontohaverightandleftearcanalsthataredifferentsizesandmust,therefore,be

fittedwithearplugsthatareseparatelysizedforeachear.Earcanalsshouldbeinspectedto

assurethatnophysicalproblems,suchasinfectionsorexcessiveearwax,willcompromiseor

complicatetheuseofhearingprotectors.

EmployeesmustbegiventheopportunitytoselecttheirHPDsfromasuitablevariety.

Generally,thisshouldincludeaminimumoftwodevices,representativeofatleasttwo

differenttypes.

TheemployermustprovidetrainingintheuseandcareofallHPDsprovidedto

employees.

Theemployer

must

ensure

proper

initial

fitting

of

HPDs

and

supervise

their

correct

use.

Programimplementersshouldbealertforcommonpitfallsassociatedwithuseandcareof

hearingprotectors.Forexample,motorcyclehelmets,personalstereoheadsets,swimmer's

earplugs,andhearingaidscannotbesubstitutedforhearingprotectors.Programimplementers

shouldbeproactiveinworkingwithemployeestoavoidsuchpitfalls.

HPDAttenuation

AttenuationreferstothedampingordecreaseofnoiselevelsasaresultofwearingHPDs.

TheemployermustevaluateHPDattenuationforthespecificnoiseenvironmentsin

whichthe

HPD

will

be

used.

HPDsmustattenuateemployeeexposuretoatleastaneighthourtimeweighted

averageof90dBA.

Foremployeeswhohaveexperiencedastandardthresholdshift(STS),HPDsmust

attenuateexposureatorbelowtheactionlevelof85dBATWA(timeweighted

average).


29/85



TheadequacyoftheHPDsmustbereevaluatedwheneveremployeenoiseexposures

increasetotheextentthattheymaynolongerprovideadequateattenuation.The

employermustprovidemoreeffectivehearingprotectorsasnecessary.

EmployerneedstoknowandunderstandthemethodsforestimatingHPDattenuation.

HearingProtectionLabeling

WhenOSHAdisseminateditsHearingConservationAmendmentin1983,itincorporatedthe

EPAlabelingrequirementsforhearingprotectors,whichrequiredmanufacturerstoidentifythe

noisereductioncapabilityofallhearingprotectorsonthehearingprotectorpackage.This

measureisreferredtoasthenoisereductionrating(NRR).Itisalaboratoryderivednumerical

estimateoftheattenuationachievedbytheprotector.Itbecameevidentthattheamountof

protectionuserswerereceivingintheworkplacewiththeprescribedhearingprotectorsdidnot

correlatewiththeattenuationindicatedbytheNRR.

OSHAacknowledged

that

in

most

cases,

the

NRR

overstated

the

protection

afforded

to

workers

andrequiredtheapplicationforcertaincircumstancesofasafetyfactorof50%totheNRR,

aboveandbeyondthe7dBsubtractioncalledforwhenusingAweightedmeasurements.For

example,consideraworkerwhoisexposedto98dBAfor8hoursandwhosehearing

protectorshaveanNRRof25dB.Wecanestimatetheworkersresultantexposureusingthe

50%safetyfactor.Theworkersresultantexposureis89dBAinthiscase.

The50%safetyfactoradjustslabeledNRRvaluesforworkplaceconditionsandisusedwhen

consideringwhetherengineeringcontrolsaretobeimplemented.

EstimateddBAexposure=TWA(dBA) [(257)x50%]=89dBA

In1997,ANSIpublishedanewtestmethod(subjectfit)formeasuringtherealearattenuation

ofhearingprotectors(ANSIS12.61997).Thismethodprovidesmorerepresentativeestimates

oftherealworldperformanceofhearingprotectors.Itattemptstobetterapproximatethe

protectionattainedinrealworkplacesbyusinguntrainedsubjectsinthetestmethod(theonly

instructiontheyreceiveistheinstructionthatcomeswiththepackage)tocloselyreplicatereal

worldusers.

Somemanufacturersofhearingprotectorsaretestingtheirproductsaccordingtothesubject

fitmethodofANSIS12.61997.Youmaycontactthemanufacturertorequestsuchdata.

Inthefuture,hearingprotectormanufacturerswhovoluntarilytesttheirproductaccordingto

thesubjectfitmethodmaychoosetopublishtheprotector'sattenuationdata.


30/85



EmployeeTrainingandEducation

Theemployermustinstituteatrainingprogramforallemployeeswithnoiseexposuresator

abovetheactionlevelandensureemployeeparticipation.

Trainingmustberepeatedannuallyforeachemployeeinthehearingconservation

program.[29CFR1910.95(k)(2)]

Informationmustbeupdatedtobeconsistentwithchangesinprotectiveequipment

andworkprocesses.[29CFR1910.95(k)(2)]

Anemployeesfailuretocorrectlyinsertanearplugoradjustanearmuffarearguablythechief

culpritsresponsiblefordiminishedrealworldhearingprotection.Thus,evenifanemployeehas

beenissuedacorrectlysizedhearingprotectorandhasbeentrainedinitsuseandcare,itis

quitepossiblethatheorshecouldreceivelittleornoeffectivehearingprotectionbecauseofa

faultyfit.Employeesmustresolvetoweartheirhearingprotectioncorrectly,ortheywillgreatly

reduceits

ability

to

prevent

harmful

noise

from

damaging

their

hearing.

Willfulfailuretowearhearingprotectionshouldbetakenseriously.Employeesshouldconsider

thatmanagementisresponsibleforensuringcompliancewithhealthandsafetyrequirements.

Shouldemployeesfailtoweartheirhearingprotection,managementcanbeheldaccountable

andmaybecitedandpenalizedfornoncompliancewithhealthandsafetyregulations.

Partoftheemployeesresponsibilitytowardwearingtheirhearingprotectoristocultivatea

vigilantattitudeabouthearingprotection.Employeesshouldexpecttheirhearingprotectorsto

slipor

work

lose

over

aperiod

of

time.

Throughout

their

work

shift,

employees

must

periodicallychecktoseeiftheyneedtoreadjustorrefittheirprotectorinordertomaintaina

reliablefit.

Hearingprotectorsbreakandbecomeworn.Employeesalsoneedtochecktheirprotector

regularlyandtoseekrepairorreplacementwhenevernecessary.Lastly,theycanhelpeach

otherbyencouragingtheircoworkerstousehearingprotectorsandtoseekhelpwhenthey

haveproblems.

Employeesmust

guard

against

acquiring

afalse

sense

of

safety.

As

the

discussion

and

figures

in

thissectionhaveillustrated,itiseasytomisusehearingprotectorsandgreatlyreducetheir

effectiveness.EmployeesCANprevailovermosthearinghealthhazardsifthey:1)properly

weartheirhearingprotectors,2)exerciseacommitmenttoweartheirhearingprotectors

consistently,and3)maintaintheirhearingprotectorsbyrepairingorreplacingthemwhen

necessary.


31/85



Theemployermustensurethateachemployeeisinformedofthefollowing:

Theeffectsofnoiseonhearing.

Thepurposeofhearingprotectors;advantages,disadvantagesandattenuationof

varioustypes;andinstructionsonselection,fitting,useandcare.

Thepurpose

of

audiometric

testing

and

an

explanation

of

test

procedures.

AccesstoInformationandTrainingMaterials

Theemployermust:

Makecopiesofthenoisestandardavailabletoaffectedemployeesortheirrepresentativesand

postacopyintheworkplace.

Provideaffectedemployeeswithanyinformationalmaterialspertainingtothestandardthatare

suppliedtotheemployerbyOSHA.

Provide,uponrequest,allmaterialrelatingtotheemployer'strainingandeducationprogramto

OSHA.

Greatjob! Yourenearlyhalfwaythroughtheprogram


32/85



Module4Quiz



submitted.

1.

Whatis

considered

the

last

option

to

control

exposures

to

noise?

a. Hearingprotectiondevices(HPDs)

b.

Engineeringcontrols

c.

Newequipmentwithsoundabsorbingenhancements

d.

Bothbandc

2. Whataremanagementstworolesinensuringthathearingprotectiondevices

protecthearingeffectively?

a. facilitationandenforcement

b. disciplineandenforcement

c. correctiveactionandfacilitation

d.

employeeparticipation

and

encouragement

3.

EmployersmustmakeHPDsavailabletoallemployeesexposedatorabovethe

actionlevel.Thesemustbeprovided_____.

a. atnocosttoemployees

b. mustbereplacedasnecessaryc. onanannualbasis

d. Bothaandb

e. Alloftheabove

4. EmployeesmustbegiventheopportunitytoselecttheirHPDsfromasuitable

variety.Generally,

this

should

include

aminimum

of

_____

devices,

representativeofatleasttwodifferenttypes.

a. one

b. two

c. three

d. four

5.

Whatistheactionlevelatwhichtheemployermustinstituteatraining

programforallemployeeswithnoiseexposuresandensuretheir

participation?

a.

80dBA

b. 85dBA

c. 90dBA

d. 100dBA


33/85



6.

Howoftenmusttrainingbecompletedforeachemployeeinthehearing

conservationprogram?

a. annually

b.

biannually

c. everysixmonths

d.

everytwo

years

7. Theemployermustprovidetraininginthe_____and_____ofallHPDs

providedtoemployees.

a. care,limitations

b. use,care

c. use,limitations

d. benefits,limitations

8. Theemployermustensuretheproper_____ofHPDsandsupervisetheir

correctuse.

a. initialfitting

b. color

c. safetyrating

d.

Bothbandc

e. Alloftheabove


34/85



Module5: HearingConservationProgramBenefits

Introduction

Whenacompanyhasaneffectivehearingconservationprogram,everyonewinsthe

employers,theemployees,andthesafetyandhealthprofessionalswhoimplementthe

program.This

course

is

not

about

minimal

criteria

that

meet

only

the

letter

of

the

law.

It

is

concernedwithprogramsthatareeffectiveaswellasefficient:thoseoptimizingprogram

elementsthatsucceedinpreventinghearinglossinapracticalandcosteffectivemanner.

TheCosts

InWashingtonState,workers'compensationdisabilitysettlementsforhearingrelated

conditionscost$4.8millionin1991(notincludingmedicalcosts).Whenappliedtothenational

workforce,occupationalhearinglosscostsanestimated$242.4millionperyearindisability

alone.

Thisfiguredoesnotincludemedicalcostsorpersonalcostswhichcanincludeapproximately

$1500forahearingaidandaround$300peryearforbatteries.Moreover,workers'

compensationdataisanunderestimateofthetruefrequencyofoccupationalillness,

representingonlythetipoftheiceberg.

InBritishColumbia,inafiveyearperiodfrom1994to1998,theworkers'compensationboard

paid$18millioninpermanentdisabilityawardsto3,207workerssufferinghearingloss.An

additional$36millionwaspaidoutforhearingaids.

Through

their

hearing

conservation

program,

the

U.S.

Army

saved

$504.3

million

by

reducing

hearinglossamongcombatarmspersonnelbetween1974and1994.TheDepartmentof

VeteransAffairssaved$220.8millionandtheArmyanadditional$149millionbyreducing

civilianhearinglossbetween1987and1997.

EmployerBenefits

Agoodhearingconservationprogramisgoodbusiness.Itpromotesgoodlaborrelations

becauseemployeesknowthatmanagementisconcerned,andthistypeofconcernmay

translatetoimprovedproductivityandproductquality.Indeed,noiseitselfcanhaveanadverse

effectonproductivity.Forcomplexjobsandthoserequiringconcentration,studiesshowthat

greaterefficiency

is

linked

to

lower

noise

levels.

Also,

the

ease

and

accuracy

of

communication

isimprovedasnoiselevelsarelowered.Thesebenefitsshouldprovetobecosteffectivefor

management.Additionally,thepreventionofhearinglossleadstothepreservationofvaluable

employeeresources.


35/85



Versatility,adaptability,

and

promotability

of

employees

are

likely

to

be

maintained

when

employeesretaingoodhearing.Moralemayalsobenefit,whichshouldleadtogreater

employeesatisfactionandretention.Ofcourse,employerswhotaketheappropriate

preventiveactionnowwillgreatlyreducetheriskoffutureclaims.Aswithothereffective

healthandsafetymeasures,hearingconservationprogramsshouldalsoextendbeyondthe

workplace.

Finally,thecompanythatplacesahighvalueonsafetyandhealthmaintenanceshouldevaluate

theperformanceofmanagersresponsibleforhearingconservationprogramsandrewardthose

whoseprogramssucceedinpreventinghearingloss. Aneffectivehearingconservation

programcostsmoneytoimplement,butthenecessaryinvestmentwillproduceabeneficial

return.

EmployeeBenefits

Thehearingconservationprogram'smostobviousbenefittoemployeesisthatitsavestheir

hearingandabilitytocommunicate.Becauseoccupationalhearinglosscreepsupslowly,many

individualsareunawareoftheirimpairmentuntilitistoolate.Moreover,occupationalhearing

lossrepresentspermanentdamage,i.e.,itcannotberestoredthroughmedical/surgical

treatment.Agoodhearingconservationprogram,however,canidentifyminorchangesin

hearing,andpreventdeteriorationtothepointwhereitispermanent.Employeeswhohave

laboredfor35or40yearsshouldbeabletoenjoytheirretirement;theyshouldbeableto

socializewith

family

and

friends,

and

listen

to

music

and

the

sounds

of

nature.

Studiesofnoisycompaniesthathaveimplementedhearinglossprevention

programsshowreductionsinaccidentrates,illnesses,andlosttime.

Thecompanythatencouragesemployeestotaketheirearplugshometo

wearduringwoodworking,targetpractice,orothernoisyoffdutyactivities

isreducing

the

possibility

of

illegitimate

work

related

claims,

as

well

as

educatingtheemployeestotheneedforhearinglosspreventionin

recreationalsettings.

Hearinglossduetonoiseappearsduringthefirstfivetotenyearsofexposure,

soyoungworkersareatmostriskofnoiseinducedhearingloss.


36/85



Preventinghearinglossbenefitsemployeesallthroughlife,notjustinretirement,sincethe

abilitytocommunicateiscriticalinallofourinterpersonalrelationships.Whengoodhearingis

aprerequisiteforajob,aneffectivehearingconservationprogramwillenableemployeesto

sustaintheirhearingabilityandthuscontinuetoqualifyforjobs(perhapshigherlevel)that

havesuchrequirements.

Anotherbenefitreportedbyemployeesincompanieswitheffectivehearingconservation

programsisthattheygenerallyfeelbetter;lesstiredandirritable.Theysometimesreportthat

theysleepbetteratnight,andtheyarenolongerbotheredbytemporaryreductionsinhearing

abilityattheendoftheday,orbythetinnitus(ringingintheears)thatoftenaccompaniesthe

developmentofnoiseinducedhearingloss.

Thereisalsoevidencethatlongtermnoiseexposuremaycontributetostressrelateddisease,

especiallycardiovasculardisease.Byreducingnoise,thechancesofotherhealthimpairments

areconsequentlycontrolledandreduced.Noisereductionandmaintenanceofhearing

sensitivitycanbenefitsafetybecauseemployeesarebetterabletocommunicate,andtohear

alarmsandwarningshouts.Goodhearingisessentialformoresubtlewarningsignals,suchasa

malfunctioningmachineorthesoundsof"rooftalk"inundergroundmines.

Insummary,agoodhearingconservationprogramisconsistentwithgoodhealthandgood

business.Ataminimum,employeesbenefitwithgoodhearing.Reductionsinnoiseexposure

mayalsoresultinlessfatigueandirritation,andpossiblyfewerstressrelatedhealth

complaints.Thecompanybenefitsfromreducedworkercompensationpaymentsandmedical

expenses,andareducedlikelihoodofanOSHAcitationforhearingconservationviolations.

Reducednoiseexposuresalsocanbeassociatedwithimprovedemployeemorale,and,insome

cases,higherproductionefficiency.

Thatconcludesmodulefive Keepitup.


37/85



Module5Quiz



submitted.

1.

Forcomplex

jobs

and

those

requiring

concentration,

studies

show

that

greater

efficiencyislinkedto_____.

a. notusinghearingprotection

b. highernoiselevels

c.

lowernoiselevels

d. bothaandb

2.

The_____ofemployeesislikelytobemaintainedwhenemployeesretain

goodhearing.

a. versatility

b.

adaptability

c. promotability

d.

Alloftheabove

3.

Whoismoreatriskofdevelopinghearingloss?

a. Aworkerexposedtonoisefor1012years.

b.

Aworkerexposedtonoisethefirst510years.

c. Aworkerexposedtonoisefor1015years.

d.

Noneoftheabove

4.

Studies

of

noisy

companies

that

have

implemented

hearing

conservation

programsshowreductionsin_____.

a. accidentrates

b. illnesses

c. losttime

d. Alloftheabove

5.

Manyindividualsareunawareoftheirhearingimpairmentuntilitistoolate.

a.

True

b.

False


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Module6: HearingConservation:RequiredMonitoring

Thehearingconservationprogramrequiresemployerstomonitornoiseexposurelevelsina

waythataccuratelyidentifiesemployeesexposedtonoiseatorabove85decibels(dB)

averaged

over

8

working

hours,

or

an

8

hour

time

weighted

average

(TWA).

Employersmustmonitorallemployeeswhosenoiseexposureisequivalenttoorgreaterthana

noiseexposurereceivedin8hourswherethenoiselevelisconstantly85dB.

Theexposuremeasurementmustincludeallcontinuous,intermittent,andimpulsivenoise

withinan80dBto130dBrangeandmustbetakenduringatypicalworksituation.

Thisrequirementisperformanceorientedbecauseitallowsemployerstochoosethe

monitoring

method

that

best

suits

each

individual

situation.

Whenmusttheemployerrepeatmonitoring?

Employersmustrepeatmonitoringwheneverchangesinproduction,process,orcontrols

increasenoiseexposure.Thesechangesmaymeanthatmoreemployeesneedtobeincludedin

theprogramorthattheirhearingprotectorsmaynolongerprovideadequateprotection.

Whatisaudiometrictesting?

Audiometrictestingmonitorsanemployeeshearingovertime.Italsoprovidesanopportunity

foremployerstoeducateemployeesabouttheirhearingandtheneedtoprotectit.The

employermustestablishandmaintainanaudiometrictestingprogram.

Theimportantelementsoftheprograminclude:

baselineaudiograms

annualaudiograms

training,and

followupprocedures

Employersmustmakeaudiometrictestingavailableatnocosttoallemployeeswhoare

exposedto

an

action

level

of

85

dB

or

above,

measured

as

an

8hour

TWA.

The

audiometric

testingprogramfollowupshouldindicatewhethertheemployershearingconservation

programispreventinghearingloss.

Alicensedorcertifiedaudiologist,otolaryngologist,orotherphysicianmustberesponsiblefor

theprogram.Bothprofessionalsandtrainedtechniciansmayconductaudiometrictesting.The


40/85



professionalinchargeoftheprogramdoesnothavetobepresentwhenaqualifiedtechnician

conductstests.Theprofessionalsresponsibilitiesinclude:

overseeingtheprogramandtheworkofthetechnicians

reviewingproblemaudiograms,and

determiningwhetherreferralisnecessary.

Theemployeeneedsareferralforfurthertestingwhentestresultsarequestionableorwhen

relatedmedicalproblemsaresuspected.Ifadditionaltestingisnecessaryoriftheemployer

suspectsamedicalpathologyoftheearthatiscausedoraggravatedbywearinghearing

protectors,theemployermustrefertheemployeeforaclinicalaudiologicalevaluation.There

aretwotypesofaudiogramsrequiredinthehearingconservationprogram:baselineand

annualaudiograms.

Whatisabaselineaudiogram?

Thebaseline

audiogram

is

the

reference

audiogram

against

which

future

audiograms

are

compared.Employersmustprovidebaselineaudiogramswithin6monthsofanemployeesfirst

exposureatorabovean8hourTWAof85dB.Anexceptionisallowedwhentheemployeruses

amobiletestvanforaudiograms.Intheseinstances,baselineaudiogramsmustbecompleted

within1yearafteranemployeesfirstexposuretoworkplacenoiseatoraboveaTWAof85dB.

Employees,however,mustbefittedwith,issued,andrequiredtowearhearingprotectors

whenevertheyareexposedtonoiselevelsaboveaTWAof85dBforanyperiodexceeding6

monthsaftertheirfirstexposureuntilthebaselineaudiogramisconducted.Employeesshould

notbeexposedtoworkplacenoisefor14hoursbeforethebaselinetestorwearhearing

protectorsduring

this

time

period.

Whatareannualaudiograms?

Employersmustprovideannualaudiogramswithin1yearofthebaseline.Itisimportanttotest

workershearingannuallytoidentifydeteriorationintheirhearingabilityasearlyaspossible.

Thisenablesemployerstoinitiateprotectivefollowupmeasuresbeforehearingloss

progresses.

Employersmustcompareannualaudiogramstobaselineaudiogramstodeterminewhetherthe

audiogramis

valid

and

whether

the

employee

has

lost

hearing

ability

or

experienced

astandard

thresholdshift(STS).AnSTSisanaverageshiftineitherearof10dBormoreat2,000,3,000,

and4,000hertz.


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Whatisanemployerrequiredtodofollowinganaudiogramevaluation?

TheemployermustfitorrefitanyemployeeshowinganSTSwithadequatehearingprotectors,

showtheemployeehowtousethem,andrequiretheemployeetowearthem.Employersmust

notifyemployeeswithin21daysafterthedeterminationthattheiraudiometrictestresults

showanSTS.

SomeemployeeswithanSTSmayneedfurthertestingiftheprofessionaldeterminesthattheir

testresultsarequestionableoriftheyhaveanearproblemthoughttobecausedoraggravated

bywearinghearingprotectors.Ifthesuspectedmedicalproblemisnotthoughttoberelatedto

wearinghearingprotection,theemployermustadvisetheemployeetoseeaphysician.

IfsubsequentaudiometrictestsshowthattheSTSidentifiedonapreviousaudiogramisnot

persistent,employeeswhoseexposuretonoiseislessthanaTWAof90dBmaystopwearing

hearingprotectors.

Theemployermaysubstituteanannualaudiogramfortheoriginalbaselineaudiogramifthe

professionalsupervisingtheaudiometricprogramdeterminesthattheemployeesSTSis

persistent.Theemployermustretaintheoriginalbaselineaudiogram,however,forthelength

oftheemployeesemployment.Thissubstitutionwillensurethatthesameshiftisnot

repeatedlyidentified.Theprofessionalalsomaydecidetorevisethebaselineaudiogramifthe

employeeshearingimproves.Thiswillensurethatthebaselinereflectsactualhearing

thresholdstotheextentpossible.

Whenshouldanemployerperformanaudiogram?

Formaximumprotectionoftheemployees(andforthatmatter,thecompany),audiograms

shouldbeperformed:

1.duringpreemployment;

2.priortoinitialassignmentinahearinghazardousworkarea;

3.annuallyaslongastheemployeeisassignedtoanoisyjob;

4.atthetimeofreassignmentoutofahearinghazardousjob;and

5.attheterminationofemployment.

Inaddition,

it

is

suggested

that

employees

who

are

not

exposed

be

given

periodic

audiograms

aspartofthecompany'shealthcareprogram.Theaudiogramsoftheseemployeescanbe

comparedtothoseoftheexposedemployeeswhenevertheoveralleffectivenessofthe

hearingconservationprogramisevaluated.Inanoptimallyeffectiveprogram,thetwo

employeegroupswillshowessentiallythesameamountofaudiometricchange.


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Whenareemployeesrequiredtowearhearingprotectors?

Employeesmustwearhearingprotectors:

foranyperiodexceeding6monthsfromthetimetheyarefirstexposedto8hourTWA

noiselevelsof85dBorabove,untiltheyreceivetheirbaselineaudiogramsifthesetests

aredelayedduetomobiletestvanscheduling;

iftheyhaveincurredstandardthresholdshiftsthatdemonstratetheyaresusceptibleto

noise;and

iftheyareexposedtonoiseoverthepermissibleexposurelimitof90dBoveran8hour

TWA.

Employersshouldprovideemployeeswithaselectionofatleastonevarietyofhearingplugand

onevarietyofhearingmuffs.

NoiseReductionRatings(NRR)

Hearingprotectors

must

adequately

reduce

the

noise

level

for

each

employees

work

environment.MostemployersusetheNoiseReductionRating(NRR)thatrepresentsthe

protectorsabilitytoreducenoiseunderideallaboratoryconditions.Theemployerthenadjusts

theNRRtoreflectnoisereductionintheactualworkingenvironment.

StandardThresholdShift(STS)

OSHA'sdefinitionofastandardthresholdshiftisachange,relativetobaseline,of10dBor

moreintheaveragehearinglevelat2000,3000,and4000Hzineitherear.

NIOSHsdefinition

of

significant

threshold

shift

is

a15

dB

change

at

any

of

the

frequencies

500,

1000,2000,3000,4000,or6000Hz,demonstratedonarepeataudiogramforthesameearand

samefrequency,withtheretestbeingadministeredimmediatelyaftertheaudiogramthat

showedtheshiftascomparedtothebaselineaudiogram.

WhatTrainingisrequired?

Employeetrainingisveryimportant.Workerswhounderstandthereasonsforthehearing

conservationprogramsandtheneedtoprotecttheirhearingwillbemoremotivatedtowear

theirprotectorsandtakeaudiometrictests.

EmployersmusttrainemployeesexposedtoTWAsof85dBandaboveatleastannuallyin:

theeffectsofnoise;

thepurpose,advantages,anddisadvantagesofvarioustypesofhearingprotectors;

theselection,fit,andcareofprotectors;and

thepurposeandproceduresofaudiometrictesting


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Thetrainingprogrammaybestructuredinanyformat,withdifferentportionsconductedby

differentindividualsandatdifferenttimes,aslongastherequiredtopicsarecovered.

Whatexposureandtestingrecordsmustemployerskeep?

Employersmustkeepnoiseexposuremeasurementrecordsfor2yearsandmaintainrecordsof

audiometrictestresultsforthedurationoftheaffectedemployeesemployment.Audiometric

testrecordsmustincludetheemployeesnameandjobclassification,date,examinersname,

dateofthelastacousticorexhaustivecalibration,measurementsofthebackgroundsound

pressurelevelsinaudiometrictestrooms,andtheemployeesmostrecentnoiseexposure

measurement.

Employersarerequiredtorecordworkrelatedhearinglosscaseswhenanemployeeshearing

testshowsamarkeddecreaseinoverallhearing.Employerswillbeabletomakeadjustments

forhearinglosscausedbyaging,seektheadviceofaphysicianorlicensedhealthcare

professionaltodetermineifthelossisworkrelated,andperformadditionalhearingteststo

verifythepersistenceofthehearingloss.

ManagementResponsibilities

Managersshouldsupporttheaudiometricevaluationphasebyallocatingsufficientresources.

Managementmustensureallemployees(evenmobile/itinerantworkers)areincludedinthe

audiometricphase.

Managementmayopttocontractforaudiometricserviceswithanexternalsourcesuchasa

mobiletesting

contractor

or

alocal

hearing

clinic.

Alternatively,

management

may

choose

to

purchaseaudiometricequipmentandtrainacompanyemployeetoperformaudiometric

testingonsiteunderthesupervisionofanaudiologistoraqualifiedphysician.Thethirdoption

istocombineinternalandexternalresources.Thechoicedependsuponeconomic

considerationsaswellasthesize,policies,andgeographicallocationofthecompany.If

contractservicesareused,itiscriticallyimportantthatmanagementstillassignresponsibility

foroverseeingthehearingconservationprogramtoakeyonsiteindividual.

Allemployees,notjustthosewiththresholdshifts,shouldreceivepromptwrittensummariesof

theircurrent

hearing

status

from

the

professional

reviewer.

Employees

also

should

receive

summariesoftheirhearingtrendsovertime,alongwithrecommendationsforfurther

evaluationoranyextraprecautionsneeded,suchasmorecarefuluseofhearingprotectors.

Anothermodulecompleted. Goodjob


44/85



Module6Quiz



submitted.

1.

Employersmust

monitor

all

employees

whose

noise

exposure

is

equivalent

to

orgreaterthananoiseexposurereceivedin8hourswherethenoiselevelis

constantly_____dB.

a.

80

b. 85

c. 88

d. 90

2.

Employersmustprovide_____audiogramswithin6monthsofanemployees

firstexposureatorabovean8hourTWAof85dB.

a. Annual

b. Baseline

c. Centerline

d.

Yearly

3.

Employersmustprovideannualaudiogramswithin_____year(s)ofthe

baseline.

a. two

b. one

c. three

d.

four

4.

Formaximumprotectionoftheemployees(andforthatmatter,thecompany),

audiogramsshouldbeperformedonwhichofthefollowingoccasions?

a. Preemployment. Priortoinitialassignmentinahearinghazardousworkarea.

b. Annually,aslongastheemployeeisassignedtoanoisyjob(atimeweighted

average.

c. Atthetimeofreassignmentoutofahearinghazardousjob,andatthetermination

ofemployment.

d. Alloftheabove


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5.

NIOSHsdefinitionofsignificantthresholdshiftisa_____dBchangeatanyof

thefrequencies500,1000,2000,3000,4000,or6000Hz,demonstratedona

repeataudiogramforthesameearandsamefrequency,withtheretestbeing

administeredimmediatelyaftertheaudiogramthatshowedtheshiftas

comparedtothebaselineaudiogram.

a.

10

b. 5

c. 15

d. 3

6.

Employersmustkeepnoiseexposuremeasurementrecordsfor_____years.

a.

one

b.

two

c. three

d. four

Pleasenote:modules79areoptional,thefinalexamonlyincludescoursematerialfrom

modules16. Ifyouwishtodoso,youmaynowproceedtothefinalexambygoingto

www.oshatrain.org


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Module7:HearingConservationProgramAudit(Optional)

Introduction

Preventingoccupationalhearinglossisacomplexmatter,butitisoftenenteredintowithout

firstassessingtheassetsavailable,theassetsrequired,andtheexpectedoutcomeofthe

program.Before

any

program

to

prevent

hearing

loss

is

put

into

place,

or

before

any

changes

in

anexistingprogramaremade,anauditshouldbeperformedonthesystemasitexists.Many

companiesdeclinetoperformanauditbecausetheyeithercantconceiveofaneedforitor

dontrecognizeitsvalueasthefoundationofasuccessfulprogram.Ahearingconservation

programauditshouldbeconsideredasimportanttotheoutcomeoftheprogramasisa

businessplantothesuccessofthecompany.

Programevaluationchecklist,canservewell.

Itisbesttoperformtheauditfromthetopdown,withadministrativeissuesaddressedfirst.In

theUnited

States,

occupational

safety

and

health

programs

historically

have

been

driven

by

regulations.Thus,itisimportanttoassurethattheregulationsforhearingconservation

programsarebeingaddressedbytheprogram.Atthesametime,thereneedstobeacorporate

recognitionthataddressingonlyregulatoryissueswillnotcreateaneffectiveprogram.Good

safetyandhealthpracticesneedtobefollowed.Thecompanypolicymustbedevelopedandall

whoadministerorparticipateintheprogrammustbeawareofthepolicies.

Decisionsneedtobemadeastowhoisresponsibleforprovidingfacilitiesandmaterialsforthe

hearingconservationprogram.Decisionsalsoneedtobemadeaboutwhomtheprogram

implementeror

key

person

will

be

and

guidelines

for

evaluating

the

effectiveness

of

that

personneedtobeestablished.Theroleofsupervisorsintheprogramshouldbeestablished.If

frontlinesupervisorshavearole,therolemustbedefinedandprocedurestonotify

supervisorsandtrainthemintheirroleshouldbeestablished.

Hazardassessmentsshouldbeaddressedduringtheaudit.Theauditshoulddetermineif

appropriatemeasurementshavebeentaken.Methodsshouldbedevelopedtoevaluatethe

resultsofhazardmeasurement.Whowillnotifyemployeesandhowtheywillbenotifiedofthe

resultsofhazardmeasurementshouldbedetermined.Itisimportanttoidentifythecritical

measurementsthat

need

to

be

taken

and

how

often

they

should

be

751 Study Guide

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