National Fire Protection Association Report … · National Fire Protection Association 1 Batterymarch Park, Quincy, MA 02169-7471 ... The definition for “process seal” is contained

National Fire Protection Association 1 Batterymarch Park, Quincy, MA 02169-7471 Phone: 617-770-3000 • Fax: 617-770-0700 • www.nfpa.org

M E M O R A N D U M

To: NEC Code-Making Panel 14

From: Kimberly Shea, Project Administrator

Date: April 16, 2015

Subject: NEC First Draft TC FINAL Ballot Results (A2016)

According to the final ballot results, all ballot items received the necessary affirmative votes to pass ballot.

16 Members Eligible to Vote 1 Not Returned (Cahill) 7 Members voted Affirmative with Comment on one or more Revisions (Ankele, Bernsen, Blais,

Lawrence, Neagle, Wechsler and Wirfs) 9 Members voted Negative on one or more Revisions (Alexander, Ankele, Blais, Burns, Kines,

Lawrence, McBride, Simmons and Wechsler) 0 Members Abstained on one or more Revisions The attached report shows the number of affirmative, negative, and abstaining votes as well as the explanation of the vote for each first revision.

There are two criteria necessary for each first revision to pass ballot: (1) simple majority and (2) affirmative 2/3 vote. The mock examples below show how the calculations are determined.

(1) Example for Simple Majority: Assuming there are 20 vote eligible committee members, 11 affirmative votes are required to pass ballot. (Sample calculation: 20 members eligible to vote ÷ 2 = 10 + 1 = 11)

(2) Example for Affirmative 2/3: Assuming there are 20 vote eligible committee members and 1 member did not

return their ballot and 2 members abstained, the number of affirmative votes required would be 12. (Sample calculation: 20 members eligble to vote – 1 not returned – 2 abstentions = 17 x 0.66 = 11.22 = 12 )

As always please feel free to contact me if you have any questions.

First Revision No. 3910-NFPA 70-2015 [ Definition: Dusttight. ]

Dusttight.

Constructed Enclosures constructed so that dust will not enter the enclosing case under specified testconditions.

Informational Note No. 1: Enclosure Types 3, 3S, 3SX, 4, 4X, 5, 6, 6P, 12, 12K, and 13, perANSI/NEMA 250-2014, Enclosures for Electrical Equipment , are considered dusttight and suitablefor use in unclassified locations and in Class II, Division 2; Class III; and Zone 22 hazardous(classified) locations.

Informational Note No. 2: For further information, see ANSI/ISA-12.12.01-2013, NonincendiveElectrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2Hazardous (Classified) Locations .

Submitter Information Verification

Submitter Full Name: CMP 14

Organization: [ Not Specified ]

Street Address:

City:

State:

Zip:

Submittal Date: Mon Jan 12 13:34:47 EST 2015

Committee Statement

CommitteeStatement:

The definition was revised to match the deleted definitions from 500.2 and 506.2. Informationalnote no. 1 was added to clarify which enclosure types are considered to be dusttight. Informationalnote no. 2 was relocated from the deleted definitions in 500.2 and 506.2.

ResponseMessage:

Ballot Results

This item has passed ballot

16 Eligible Voters

1 Not Returned

13 Affirmative All

2 Affirmative with Comments

0 Negative with Comments

0 Abstention

Not Returned

Cahill, Corey

Affirmative All

Alexander, Harold G.

Bernsen, Marc J.

Blais, Steven J.

National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...

1 of 270 4/16/2015 11:12 AM

kshea

Text Box

Burns, Dave

Jones, Robert A.

Kines, Haywood

Lawrence, Jr., William G.

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.

Affirmative with Comment

Ankele, Donald W.

At the end of informational note 1, add the phrase :"...where heat generating parts are not included within theenclosure."

Wirfs, Mark C.

None


2 of 270 4/16/2015 11:12 AM

First Revision No. 3997-NFPA 70-2015 [ New Definition after Definition: Copper-Clad

Aluminum Condu... ]

Cord Connector [as applied to Hazardous (Classified) Locations].

A fitting intended to terminate a cord or cable to a box or similar device and reduce the strain at points oftermination and may include an explosionproof, a dust-ignitionproof, or a flameproof seal.




Street Address:

City:

State:

Zip:

Submittal Date: Fri Jan 16 15:22:46 EST 2015

Committee Statement

CommitteeStatement:

The inclusion of TC-ER and TC-ER-HL as a wiring method in Articles 501, 502, 503, 505, and 506requires a method of termination that currently is identified as a Cord Connector. The current term forthis device, as used in the HazLoc industry and within the product standards, is “cord connector”,which should not be confused with the term also used by the wiring device industry, indicating afemale electrical connector. The differentiation has been addressed by denoting “(as applied tohazardous (classified) locations)”. The term is currently used (19) times in these articles.

ResponseMessage:

Public Input No. 4476-NFPA 70-2014 [Section No. 505.15(B)(2)]

Public Input No. 4477-NFPA 70-2014 [Section No. 505.15(C)(2)]

Ballot Results


16 Eligible Voters

1 Not Returned

11 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave


3 of 270 4/16/2015 11:12 AM

Jones, Robert A.


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Simmons, John L.


Wirfs, Mark C.

None

Negative with Comment

Kines, Haywood

Definitions that are only applicable to Chapter 5 need to remain within the .2 sections within the Articles inChapter 5 so that the information needed for the user is readily available. Relocating the definitions to Article 100and adding the text (as applied to Hazardous (Classified) Locations) so users will understand the definitions onlyapply to Articles in Chapter 5 unnecessarily expands the text in Article 100 and does add any benefit to theElectrical industry using the National Electrical Code.

McBride, William E.

The term cord connector is used many times in the NEC for a wiring device. Defining that term differently for aproduct to be used in classified locations and also in unclassified locations is confusing.

Wechsler, David B.

While it is understood that confusion may exist with the term “cord connector” used in product standards it is feltthat complete resolution resides not within the NEC, but in product standards. To reduce this impact it is stronglysuggested that the term “cord fitting” be used since in fact the method of termination is incorporated often with afitting. Therefore, the revised defined term should be as follows: 100 (new) Cord Fitting (as applied to HazardousClassified Locations) A product intended to terminate a cord or cable to a box or similar device and reduce thestrain at points of termination and may include an explosionproof, a dust-ignition proof, or a flameproof seal


4 of 270 4/16/2015 11:12 AM

First Revision No. 3999-NFPA 70-2015 [ New Definition after Definition: Premises Wiring

(System). ]

Process Seal [as applied to Hazardous (Classified) Locations].

A seal between electrical systems and flammable or combustible process fluids where a failure couldallow the migration of process fluids into the premises’ wiring system.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The definition for “process seal” is contained in ANSI/ISA 12.27.01 – 2011. The term is usedin multiple articles in Chapter 5.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy


5 of 270 4/16/2015 11:12 AM

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None


Kines, Haywood



6 of 270 4/16/2015 11:12 AM

First Revision No. 3918-NFPA 70-2015 [ Section No. 500.2 [Excluding any Sub-Sections]

]

For purposes of Articles 500 through 504 and Articles 510 through 516, the following definitions apply.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

All of the definitions in this section have been moved to Article 100 to comply with Section2.2.2.1 of the 2011 NEC Style Manual.

ResponseMessage:

Public Input No. 1862-NFPA 70-2014 [Section No. 500.2]

Ballot Results


16 Eligible Voters

1 Not Returned

10 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


7 of 270 4/16/2015 11:12 AM


Ankele, Donald W.

Retain the defined terms with a reference to see Article 100 for the actual definition. For example "CombustibleDust. See Article 100 for definition." This will help the user in applying Articles 500 through 504 and 510 through516.

Wirfs, Mark C.

None


Burns, Dave

The definitions were relocated based on direction from the TCC. Panel 14 followed this direction but is unaware ifother panels followed suit. Consistancy within the document is important to the user. If the definitions are to bemoved to Art. 100, some cross-reference should be provided for this code cycle.

Kines, Haywood


McBride, William E.

For this code cycle only, a cross-reference in 500.2 to be relocated definitions in Art 100 is recommended in thislocation for sustained usability. The code panel is moving the definition without leaving a trail where the definitionis relocated to article 100 and will result in confusion for the use of this article. 500.2 should refer users of the codeto see Article 100 for definitions formerly located in Section 500.2


8 of 270 4/16/2015 11:12 AM

First Revision No. 3929-NFPA 70-2015 [ Definition: Combustible Dust. ]

Combustible Dust [as applied to Hazardous (Classified) Locations] .

Dust particles that are 500 microns or smaller (material passing a U.S. No. 35 Standard Sieve as definedin ASTM E 11-09 E 11-13 , Standard Specification for Wire Cloth and Sieves for Testing Purposes), andpresent a fire or explosion hazard when dispersed and ignited in air.

Informational Note: See ASTM E 1226–12a E1226–12a , Standard Test Method for Explosibility ofDust Clouds, or ISO 6184-1, Explosion protection systems — Part 1: Determination of explosionindices of combustible dusts in air, for procedures for determining the explosibility of dusts.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term "Combustible Dust" is used in Articles 500, 502, 504, 505, 506, and 516. The definition ofthis term has been relocated to Article 100 to comply with Section 2.2.2.1 of the 2011 NEC StyleManual. The proposed addition of the words “(as applied to Hazardous (Classified) Locations)” willmake it clear that the definition pertains to Articles 500 through 516 as applicable. References wereupdated.

ResponseMessage:

Public Input No. 1732-NFPA 70-2014 [Definition: Combustible Dust.]



Public Input No. 1812-NFPA 70-2014 [New Definition after Definition: Clothes Closet.]

Ballot Results


16 Eligible Voters

1 Not Returned

11 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All



9 of 270 4/16/2015 11:12 AM

Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None


Burns, Dave

The definitions were relocated based on direction from the TCC. Panel 14 followed this direction but is unaware ifother panels followed suit. Consistancy within the document is important to the user. If the definitions are to bemoved to Art. 100, some cross-reference should be provided for this code cycle. Its is noted that corrections to thereference are not part of this negative comment.

Kines, Haywood


McBride, William E.

For this code cycle only, a cross-reference in 500.2 to the relocated definitions in Art 100 is recommended in thislocation for sustained usability. The current plan will result in confusion for the use of this article. 500.2 shouldrefer users of the code to see Article 100 for definitions formerly located in Section 500.2


10 of 270 4/16/2015 11:12 AM

First Revision No. 3904-NFPA 70-2015 [ Definition: Combustible Gas Detection System.

]

Combustible Gas Detection System [as applied to Hazardous (Classified) Locations] .

A protection technique utilizing stationary gas detectors in industrial establishments.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Combustible Gas Detection System appears in Articles 500 and 505. The definition iscurrently in 500.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011NEC Style Manual. The proposed addition of the words “(as applied to Hazardous (Classified)Locations)” will make it clear that the definition pertains to Articles 500 through 516 as applicable.

ResponseMessage:

Public Input No. 1737-NFPA 70-2014 [Definition: Combustible Gas Detection System.]

Public Input No. 1813-NFPA 70-2014 [New Definition after Definition: Communications Equipment.]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.



11 of 270 4/16/2015 11:12 AM

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None


Kines, Haywood



12 of 270 4/16/2015 11:12 AM

First Revision No. 3906-NFPA 70-2015 [ Definition: Control Drawing. ]

Control Drawing [as applied to Hazardous (Classified) Locations] .

A drawing or other document provided by the manufacturer of the intrinsically safe or associatedapparatus, or of the nonincendive field wiring apparatus or associated nonincendive field wiring apparatus,that details the allowed interconnections between the intrinsically safe and associated apparatus orbetween the nonincendive field wiring apparatus or associated nonincendive field wiring apparatus.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Control Drawing appears in Articles 500, 501, 503, 504, 505, and 506. The definition iscurrently in 500.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011NEC Style Manual. The proposed addition of the words “as applied to Hazardous (Classified)Locations)” will make it clear that the definition pertains to Articles 500 through 516 as applicable.

ResponseMessage:

Public Input No. 1738-NFPA 70-2014 [Definition: Control Drawing.]

Public Input No. 1814-NFPA 70-2014 [New Definition after Definition: Controller.]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


13 of 270 4/16/2015 11:12 AM


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Kines, Haywood



14 of 270 4/16/2015 11:12 AM

First Revision No. 3907-NFPA 70-2015 [ Definition: Dust-Ignitionproof. ]

Dust-Ignitionproof [as applied to Hazardous (Classified) Locations] .

Equipment enclosed in a manner that excludes dusts and does not permit arcs, sparks, or heat otherwisegenerated or liberated inside of the enclosure to cause ignition of exterior accumulations or atmosphericsuspensions of a specified dust on or in the vicinity of the enclosure.

Informational Note: For further information on dustignitionproof dust-ignitionproof enclosures, seeType 9 enclosure in ANSI/ NEMA 250-2008 ANSI/UL 1202-2013 , Enclosures for ElectricalEquipment, and ANSI/UL 1203-2009 2013 , Explosionproof and Dust-Ignitionproof ElectricalEquipment for Hazardous (Classified) Locations.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Dust-Ignitionproof appears in Articles 500, 502, and 506. The definition is currently in500.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011 NEC StyleManual. The proposed addition of the words “as applied to Hazardous (Classified) Locations)” willmake it clear that the definition pertains to Articles 500 through 516 as applicable. The reference toANSI/NEMA 250 2008 was deleted because Enclosure Type 9 is no longer in the scope ofANSI/NEMA 250. The references were updated.

ResponseMessage:

Public Input No. 1369-NFPA 70-2014 [Definition: Dust-Ignitionproof.]


Public Input No. 1815-NFPA 70-2014 [New Definition after Definition: Dusttight.]


Ballot Results


16 Eligible Voters

1 Not Returned

11 Affirmative All



0 Abstention

Not Returned

Cahill, Corey


15 of 270 4/16/2015 11:12 AM

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Remove the reference to ANSI/UL 1202-2013 and strike out the title to NEMA 250.


The added text shown as "ANSI/UL 1202:2013" should not have been added. The text "Enclosures for ElectricalEquipment, and" should have been deleted as it was the title of the deleted ANSI/NEMA 250.

Wirfs, Mark C.

None on this one.


Kines, Haywood



16 of 270 4/16/2015 11:12 AM


Dusttight.

Enclosures constructed so that dust will not enter under specified test conditions.

Informational Note: See ANSI/ISA-12.12.01-2012, Nonincendive Electrical Equipment for Use inClass I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The term is already defined in Article 100.

Response Message:

Public Input No. 1740-NFPA 70-2014 [Definition: Dusttight.]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan


17 of 270 4/16/2015 11:12 AM

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

update the edition date to 2013

Wirfs, Mark C.

None.


18 of 270 4/16/2015 11:12 AM

First Revision No. 3912-NFPA 70-2015 [ Definition: Hermetically Sealed. ]

Hermetically Sealed [as applied to Hazardous (Classified) Locations] .

Equipment sealed against the entrance of an external atmosphere where the seal is made by fusion, forexample, soldering, brazing, welding, or the fusion of glass to metal.

Informational Note: For further information, see ANSI/ISA-12.12.01-2012 2013 , NonincendiveElectrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2Hazardous (Classified) Locations.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Hermetically Sealed appears in Articles 500, 501, 505, and 480. The definition is currentlyin 500.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011 NEC StyleManual. The proposed addition of the words “as applied to Hazardous (Classified) Locations)” willmake it clear that the definition pertains to Articles 500 through 516 as applicable.

ResponseMessage:

Public Input No. 1742-NFPA 70-2014 [Definition: Hermetically Sealed.]

Public Input No. 1816-NFPA 70-2014 [New Definition after Definition: Hoistway.]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave


19 of 270 4/16/2015 11:12 AM

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None


Kines, Haywood



20 of 270 4/16/2015 11:12 AM

First Revision No. 3915-NFPA 70-2015 [ Definition: Purged and Pressurized. ]

Purged and Pressurized [as applied to Hazardous (Classified) Locations] .

The process of (1) purging, supplying an enclosure with a protective gas at a sufficient flow and positivepressure to reduce the concentration of any flammable gas or vapor initially present to an acceptablelevel; and (2) pressurization, supplying an enclosure with a protective gas with or without continuous flowat sufficient pressure to prevent the entrance of a flammable gas or vapor, a combustible dust, or anignitible fiber.

Informational Note: For further information, see ANSI/NFPA 496-2013, Purged and PressurizedEnclosures for Electrical Equipment.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Purged and Pressurized appears in Articles 500, 501, 505, and 506. The definition iscurrently in 500.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011NEC Style Manual. The proposed addition of the words “(as applied to Hazardous (Classified)Locations)” will make it clear that the definition pertains to Articles 500 through 516 as applicable

ResponseMessage:

Public Input No. 1752-NFPA 70-2014 [Definition: Purged and Pressurized.]

Public Input No. 1819-NFPA 70-2014 [New Definition after Definition: Qualified Person.]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.


21 of 270 4/16/2015 11:12 AM

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None


Kines, Haywood



22 of 270 4/16/2015 11:12 AM

First Revision No. 3916-NFPA 70-2015 [ Definition: Unclassified Locations. ]

Unclassified Locations [as applied to Hazardous (Classified) Locations] .

Locations determined to be neither Class I, Division 1; Class I, Division 2; Class I, Zone 0; Class I, Zone 1;Class I, Zone 2; Class II, Division 1; Class II, Division 2; Class III, Division 1; Class III, Division 2; Zone 20;Zone 21; Zone 22; or nor any combination thereof.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Unclassified Locations appears in Articles 500, 501, 502, 503, 504, 505, 506, 511, 513,514, 516, and 400. The definition is currently in 500.2 but should be relocated to Article 100 tocomply with Section 2.2.2.1 of the 2011 NEC Style Manual. The proposed addition of the words “asapplied to Hazardous (Classified) Locations)” will make it clear that the definition pertains to Articles500 through 516 as applicable.

ResponseMessage:

Public Input No. 1754-NFPA 70-2014 [Definition: Unclassified Locations.]

Public Input No. 1820-NFPA 70-2014 [New Definition after Definition: Ungrounded.]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


23 of 270 4/16/2015 11:12 AM


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None


Kines, Haywood



24 of 270 4/16/2015 11:12 AM

First Revision No. 3913-NFPA 70-2015 [ Definitions (500.2): Nonincendiv... to Oil

Immersi... ]

Nonincendive Circuit [as applied to Hazardous (Classified) Locations] .

A circuit, other than field wiring, in which any arc or thermal effect produced under intended operatingconditions of the equipment, is not capable, under specified test conditions, of igniting the flammablegas–air, vapor–air, or dust–air mixture.

Informational Note: Conditions are described in ANSI/ISA-12.12.01-2012 2013 , NonincendiveElectrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2Hazardous (Classified) Locations.

Nonincendive Component [as applied to Hazardous (Classified) Locations] .

A component having contacts for making or breaking an incendive circuit and the contacting mechanism isconstructed so that the component is incapable of igniting the specified flammable gas–air or vapor–airmixture. The housing of a nonincendive component is not intended to exclude the flammable atmosphereor contain an explosion.

Informational Note: For further information, see ANSI/ISA-12.12.01-2012 2013 ,NonincendiveElectrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1and 2 Hazardous (Classified) Locations.

Nonincendive Equipment [as applied to Hazardous (Classified) Locations] .

Equipment having electrical/electronic circuitry that is incapable, under normal operating conditions, ofcausing ignition of a specified flammable gas–air, vapor–air, or dust–air mixture due to arcing or thermalmeans.


Nonincendive Field Wiring [as applied to Hazardous (Classified) Locations] .

Wiring that enters or leaves an equipment enclosure and, under normal operating conditions of theequipment, is not capable, due to arcing or thermal effects, of igniting the flammable gas–air, vapor–air, ordust–air mixture. Normal operation includes opening, shorting, or grounding the field wiring.

Nonincendive Field Wiring Apparatus [as applied to Hazardous (Classified) Locations] .

Apparatus intended to be connected to nonincendive field wiring.


Oil Immersion [as applied to Hazardous (Classified) Locations] .

Electrical equipment immersed in a protective liquid in such a way that an explosive atmosphere that maybe above the liquid or outside the enclosure cannot be ignited.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Nonincendive Circuit appears in Articles 500, 501, 502, and 506. Nonincendive Componentappears in Articles 500 and 501. Nonincendive Equipment appears in Articles 500, 506, and 516.


25 of 270 4/16/2015 11:12 AM

Nonincendive Field Wiring appears in Articles 500, 501, 502, 503, 504, and 506. Nonincendive FieldWiring Apparatus appears in Article 500 and in the definition of Control Drawing which will be locatedin Article 100, if a submitted PI is approved. Oil Immersion appears in Articles 500 and 505. Thedefinitions are currently in 500.2 but should be relocated to Article 100 to comply with Section 2.2.2.1of the 2011 NEC Style Manual. The proposed addition of the words “as applied to Hazardous(Classified) Locations)” will make it clear that the definition pertains to Articles 500 through 516 asapplicable

ResponseMessage:

Public Input No. 1745-NFPA 70-2014 [Definition: Nonincendive Component.]

Public Input No. 1817-NFPA 70-2014 [New Definition after Definition: Nonlinear Load.]

Public Input No. 1746-NFPA 70-2014 [Definition: Nonincendive Equipment.]

Public Input No. 1749-NFPA 70-2014 [Definition: Oil Immersion.]

Public Input No. 1747-NFPA 70-2014 [Definition: Nonincendive Field Wiring.]

Public Input No. 1743-NFPA 70-2014 [Definition: Nonincendive Circuit.]

Public Input No. 1748-NFPA 70-2014 [Definition: Nonincendive Field Wiring Apparatus.]

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Add informational note to the definition for Nonincendive Field Wiring that referenced ISA 12.12.01-2013.

Wirfs, Mark C.

None


Kines, Haywood


26 of 270 4/16/2015 11:12 AM



27 of 270 4/16/2015 11:12 AM

First Revision No. 3962-NFPA 70-2015 [ Section No. 500.4(B) ]

(B) Reference Standards.

Important information relating to topics covered in Chapter 5 may be found in other publications.

Informational Note No. 1: It is important that the authority having jurisdiction be familiar withrecorded industrial experience as well as Familiarity with the standards of the National FireProtection Association (NFPA), the American Petroleum Institute (API), and the InternationalSociety of Automation (ISA), that as well as relevant industrial experience, may be of use in theclassification of various locations, the determination of adequate ventilation, and the protectionagainst static electricity and lightning hazards.

Informational Note No. 2: For further information on the classification of locations, see NFPA30-2012 2015 , Flammable and Combustible Liquids Code; NFPA 32-2011, Standard forDrycleaning Plants; NFPA 33-2011 2015 , Standard for Spray Application Using Flammable orCombustible Materials; NFPA 34-2011 2015 , Standard for Dipping and Coating Processes UsingFlammable or Combustible Liquids; NFPA 35-2011, Standard for the Manufacture of OrganicCoatings; NFPA 36-2013, Standard for Solvent Extraction Plants; NFPA 45-2011 2015 , Standardon Fire Protection for Laboratories Using Chemicals; NFPA 55-2013, Compressed Gases andCryogenic Fluids Code; NFPA 58-2014, Liquefied Petroleum Gas Code; NFPA 59-2012 2015 ,Utility LP-Gas Plant Code; NFPA 497-2012, Recommended Practice for the Classification ofFlammable Liquids, Gases, or Vapors and of Hazardous (Classified) Locations for ElectricalInstallations in Chemical Process Areas; NFPA 499-2013, Recommended Practice for theClassification of Combustible Dusts and of Hazardous (Classified) Locations for ElectricalInstallations in Chemical Process Areas; NFPA 820-2012, Standard for Fire Protection inWastewater Treatment and Collection Facilities; ANSI/API RP 500-2012, Recommended Practicefor Classification of Locations of Electrical Installations at Petroleum Facilities Classified as Class I,Division 1 and Division 2; ISA-12.10-1988, Area Classification in Hazardous (Classified) DustLocations.

Informational Note No. 3: For further information on protection against static electricity and lightninghazards in hazardous (classified) locations, see NFPA 77-2014, Recommended Practice on StaticElectricity; NFPA 780-2014, Standard for the Installation of Lightning Protection Systems; and APIRP 2003-1998 2008 , Protection Against Ignitions Arising Out of Static Lightning and StrayCurrents.

Informational Note No. 4: For further information on ventilation, see NFPA 30-2012 2015 ,Flammable and Combustible Liquids Code; and ANSI/API RP 500-2012, Recommended Practicefor Classification of Locations for Electrical Installations at Petroleum Facilities Classified as ClassI, Division 1 and Division 2.

Informational Note No. 5: For further information on electrical systems for hazardous (classified)locations on offshore oil- and gas-producing platforms, see ANSI/API RP 14F-1999 2013 ,Recommended Practice for Design and Installation of Electrical Systems for Fixed and FloatingOffshore Petroleum Facilities for Unclassified and Class I, Division 1 and Division 2 Locations.

Informational Note No. 6: Portable or transportable equipment having self-contained powersupplies, such as battery-operated equipment, could potentially become an ignition source inhazardous (classified) locations. See ANSI/ISA-12.12.03-2011, Standard for Portable ElectronicProducts Suitable for Use in Class I and II, Division 2, Class I Zone 2 and Class III, Division 1 and2 Hazardous (Classified) Locations .




Street Address:

City:

State:

Zip:


28 of 270 4/16/2015 11:12 AM

Submittal Date: Wed Jan 14 10:33:16 EST 2015

Committee Statement

CommitteeStatement:

The informational note makes a recommendation. Section 3.1.3 of the 2011 NEC Style Manualstates that informational notes shall not contain recommendations. The text is modified to presentthe information as factual, rather than a recommendation.

References in the informational notes were updated.

Informational note no. 8 was added to (B) to retain the information on portable and transportableequipment from the definition of "Electrical and Electronic Equipment," which has been deleted.

ResponseMessage:

Public Input No. 1865-NFPA 70-2014 [Section No. 500.4(B)]

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


29 of 270 4/16/2015 11:12 AM

First Revision No. 3934-NFPA 70-2015 [ Section No. 500.5(A) ]

(A) Classifications of Locations General .

Locations shall be classified depending on the properties of the flammable gas, flammable liquid–produced vapor, combustible liquid–produced vapors, combustible dusts, or fibers/flyings that may bepresent, and the likelihood that a flammable or combustible concentration or quantity is present. Eachroom, section, or area shall be considered individually in determining its classification. Where pyrophoricmaterials are the only materials used or handled, these locations are outside the scope of this article.

Informational Note No. 1: Through the exercise of ingenuity in the layout of electrical installationsfor hazardous (classified) locations, it is frequently possible to locate much of the equipment in areduced level of classification or in an unclassified location and, thus, to reduce the amount ofspecial equipment required.

Refrigerant machinery rooms containing ammonia refrigeration systems that are equipped with adequatemechanical ventilation that operates continuously or is initiated by a detection system that alarms at 1000ppm may be classified as “unclassified” locations.

Rooms and refrigerated areas containing ammonia refrigeration systems that are equipped with adequatemechanical ventilation that operates continuously or is initiated by a detection system that alarms at 1000ppm may be classified as “unclassified” locations.

Informational Note No. 2: For further information regarding classification and ventilation of areasinvolving ammonia, see ANSI/ASHRAE 15-1994 2013 , Safety Standard for RefrigerationSystems Code for Mechanical Refrigeration , and ANSI/CGA G2.1-1989, Safety Requirements forthe Storage and Handling of Anhydrous Ammonia .




Street Address:

City:

State:

Zip:

Submittal Date: Tue Jan 13 10:47:31 EST 2015

Committee Statement

CommitteeStatement:

Section 500.5(A) is applicable to Sections 500.5(B), 500.5(C), and 500.5(D). Therefore, the text of500.5(A) has been retitled as “General.”

Standards name and date were updated. ANSI/CGA G2.1 reference was removed, as it is notapplicable to ammonia systems. The revision clarifies that areas containing ammonia refrigerationmay be classified as “unclassified” locations based on the use of gas detection and adequateventilation, in order to harmonize with the ASHRAE standard.

ResponseMessage:


Ballot Results


16 Eligible Voters


30 of 270 4/16/2015 11:12 AM

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Neagle, Jeremy

The phrase 'mechanical ventilation that operates continuously or is initiated by a detection system that alarms at1000 ppm' may not provide the user with enough information to select, install and operate a gas detection systemadequate for the task. Consider including a reference to 505.8(I) or ANSI/ISA 60079-29-2 and ANSI/ISATR12.13.03 for guidance on gas detection systems.

Wirfs, Mark C.

The Task Group developed the change of the (A) title to GENERAL based on applicability and context coverage.They FAILED to do the SAME for 505.5 (A) and 506.5(A). The same logic and style manual basis applies and thisshould have bee ALSO changed.


31 of 270 4/16/2015 11:12 AM


]

For purposes of testing, approval, and area classification, various air mixtures (not oxygen-enriched) shallbe grouped in accordance with 500.6(A) and (B).

Exception: Equipment identified for a specific gas, vapor, or dust, or fiber/flying .

Informational Note: This grouping is based on the characteristics of the materials. Facilities areavailable for testing and identifying equipment for use in the various atmospheric groups.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The revision adds fibers/flyings to the list, which was missing.

Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan


32 of 270 4/16/2015 11:12 AM

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Remove the reference to dust and fibers/flyings as there are no testing, approval or area classificationrequirements that address one specific dust or fiber/flying.

Wirfs, Mark C.

None.



"or fiber/flying" should not be added. "dust" should be deleted. 1. The product standards do not include such aproduct marking. a. ANSI/ISA 12.12.01 only addresses marking for a specific gas or vapour. b. ANSI/UL 1203 onlyaddresses marking for a specific gas or vapour. 2. IEC TC31 has made it quite clear that complete identification ofa specific dust or fiber/flying would involve such detail that it is not practical. It is not as simple as identifying thechemical formula of a gas or vapor. Aspects such as the chemical formula or CAS number of each constituent,along with amount of percentage of each, the bulk density, and the particle density could all be important. 3. Theproduct standards for dusts or fibers/flyings are based on particle size (for exclusion) and maximum surfacetemperature (for layer/cloud ignition). For a small portion of Intrinsic Safety, protection is based on limitation ofavailable energy to initiate an explosion. The maximum permitted energy of ~160?J is very conservative for dust.4. All known equipment can be accommodated within the requirements of the existing equipment standards.There is no need to add additional confusion as to what is and is not suitable. 5. At one time, there may have beena need due to the temperature restrictions of Table 500.8(D)(2), but that requirement was removed ~20 years ago.


33 of 270 4/16/2015 11:12 AM

First Revision No. 3935-NFPA 70-2015 [ Section No. 500.6(A)(4) ]

(4) Group D.

Flammable gas, flammable liquid–produced vapor, or combustible liquid–produced vapor mixed with airthat may burn or explode, having either a maximum experimental safe gap (MESG) value greater than0.75 mm or a minimum igniting current ratio (MIC ratio) (MIC) ratio greater than 0.80. [497:3.3.5.1.4]

Informational Note No. 1: A typical Class I, Group D material is propane. [ 497: 3.3.5.1.4]

Informational Note No. 2: For classification of areas involving ammonia atmospheres, seeANSI/ASHRAE 15-1994 2013 , Safety Code for Mechanical Refrigeration Standard forRefrigeration Systems , and ANSI/CGA G2.1-1989, Safety Requirements for the Storage andHandling of Anhydrous Ammonia .




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Standards name and date update. ANSI/CGA G2.1 reference removed as it is not applicableto ammonia systems.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

11 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


34 of 270 4/16/2015 11:12 AM

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.


Ankele, Donald W.

Due to this being extracted text, do not make the revision to MIC ratio in order to align with the indicatedextraction.


the edits shown to "MIC Ratio" should not be implemented. The extracted text should be shown exactly as it is inNFPA 497.

Wirfs, Mark C.

NONE>


Wechsler, David B.

Mr. Ankele and Mr. Lawrence are correct. Extracted material should be shown exactly as found in the sourcedocument and should not be revised as had been reflected in this case. However an affirmative with commentvote does not represent the correct action for this condition using extracted material within the NEC. The CCshould challenge and correct this practice which does not seem to follow the NFPA manual of style.


35 of 270 4/16/2015 11:12 AM

First Revision No. 3961-NFPA 70-2015 [ Section No. 500.6(B)(2) ]

(2) Group F.

Atmospheres containing combustible carbonaceous dusts that have more than 8 percent total entrappedvolatiles (see ASTM D 3175-02 D3175-11 , Standard Test Method for Volatile Matter in the AnalysisSample for Coal and Coke, for coal and coke dusts) or that have been sensitized by other materials sothat they present an explosion hazard. [ 499: 3.3.4.2] Coal, carbon black, charcoal, and coke dusts areexamples of carbonaceous dusts. [499:A. 3.3.4.2]

Informational Note: Testing of specific dust samples, following established ASTM testingprocedures, is a method used to identify the combustibility of a specific dust and the need toclassify those locations containing that material as Group F.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The reference was updated.

Response Message:


Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood



36 of 270 4/16/2015 11:12 AM

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.


Ankele, Donald W.

Due to this being extracted text, undo the edit and drop the date on D 3175 in order to align with the indicatedextraction.

Wirfs, Mark C.

NONE


Wechsler, David B.

Extracted material should be shown exactly as found in the source document and should not be revised as hadbeen reflected in this case. However an affirmative with comment vote does not represent the correct action forthis condition using extracted material within the NEC. The CC should challenge and correct this practice whichseems not to follow the NFPA manual of style.


37 of 270 4/16/2015 11:12 AM

First Revision No. 3937-NFPA 70-2015 [ Section No. 500.7(K) [Excluding any

Sub-Sections] ]

A combustible gas detection system shall be permitted as a means of protection in industrialestablishments with restricted public access and where the conditions of maintenance and supervisionensure that only qualified persons service the installation. Where such a system is installed, equipmentspecified in 500.7(K)(1), (K)(2), or (K)(3) shall be permitted.

The type of detection equipment, its listing, installation location(s), alarm and shutdown criteria, andcalibration frequency shall be documented when where combustible gas detectors are used as aprotection technique.

Informational Note No. 1: For further information, see ANSI/ISA-60079-29-1 (12.13.01)-2013 ,Explosive Atmospheres — Part 29-1: Gas detectors — Performance requirements of detectors forflammable gases, and ANSI/UL 2075, Gas and Vapor Detectors and Sensors .

Informational Note No. 2: For further information, see ANSI/API RP 500–Revised 2002 500–2012 ,Recommended Practice for Classification of Locations for Electrical Installations at PetroleumFacilities Classified as Class I, Division I or Division 2.

Informational Note No. 3: For further information, see ANSI/ISA-60079-29-2009 2 (12.13.02)-2012 ,Explosive Atmospheres — Part 29-2: Gas detectors — Selection, installation, use and maintenanceof detectors for flammable gases and oxygen.

Informational Note No. 4: For further information, see ISA-TR12.13.03-2009, Guide for CombustibleGas Detection as a Method of Protection.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The references have been updated. Removed reference to ANSI/UL 2075, as ISA-60079-29-1is the primary applicable US national standard for this application.

ResponseMessage:

Public Input No. 1620-NFPA 70-2014 [Section No. 500.7(K)]

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention


38 of 270 4/16/2015 11:12 AM

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


39 of 270 4/16/2015 11:12 AM


(A) Suitability.

Suitability of identified equipment shall be determined by one of the following:

(1) Equipment listing or labeling

(2) Evidence of equipment evaluation from a qualified testing laboratory or inspection agency concernedwith product evaluation

(3) Evidence acceptable to the authority having jurisdiction such as a manufacturer's self-evaluation oran owner's engineering judgment.

Informational Note: Additional documentation for equipment may include certificates demonstratingcompliance with applicable equipment standards, indicating special conditions of use, and otherpertinent information. Guidelines for certificates may be found in ANSI/ISA 12.00.02 UL120002:2014 , Certificate Standard for AEx Equipment for Hazardous (Classified) Locations.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The reference was updated.

Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.


40 of 270 4/16/2015 11:12 AM

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


41 of 270 4/16/2015 11:12 AM

First Revision No. 3984-NFPA 70-2015 [ Section No. 500.8(C)(3) ]

(3) Material Classification Group.

The marking shall specify the applicable material classification group(s) or specific gas, vapor, dust, orfiber/flying in accordance with 500.6.

Exception: Fixed luminaires marked for use only in Class I, Division 2 or Class II, Division 2 locationsshall not be required to indicate the group.

Informational Note: A specific gas, vapor, dust, or fiber/flying is typically identified by the genericname, chemical formula, CAS number, or combination thereof.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The revised text allows the marking of a specific material in accordance with 500.6.

Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy


42 of 270 4/16/2015 11:12 AM

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

The change to (3) should be to only add the text "or specific gas or vapor." HazLoc standards exist such as ANSIISA 12.12.01 and ANSI UL 1203 have such provision for marking of a specific gas or vapor in place of a gasgroup. There are no published requirements for the construction, testing and marking for a specific dust, fiber orflying. Similarly regarding the note, remove reference to dust and fiber/flying.

Wirfs, Mark C.

None.



The text "dust or fiber/flying" should not be added. The Informational Note should read: "A specific gas or vapouris typically identified by the chemical formula" 1. The product standards do not include such a product marking fordusts or fiber/flying. a. ANSI/ISA 12.12.01 only addresses marking for a specific gas or vapour. b. ANSI/UL 1203only addresses marking for a specific gas or vapour. 2. IEC TC31 has made it quite clear that completeidentification of a specific dust or fiber/flying would involve such detail that it is not practical. It is not as simple asidentifying the chemical formula of a gas or vapor. Aspects such as the chemical formula or CAS number of eachconstituent, along with amount of percentage of each, the bulk density, and the particle density could all beimportant. 3. The product standards for dusts or fibers/flyings are based on particle size (for exclusion) andmaximum surface temperature (for layer/cloud ignition). For a small portion of Intrinsic Safety, protection is basedon limitation of available energy to initiate an explosion. The maximum permitted energy of ~160?J is veryconservative for dust. 4. All known equipment can be accommodated within the requirements of the existingequipment standards. There is no need to add additional confusion as to what is and is not suitable. 5. At onetime, there may have been a need due to the temperature restrictions of Table 500.8(D)(2), but that requirementwas removed ~20 years ago.


43 of 270 4/16/2015 11:12 AM

First Revision No. 3982-NFPA 70-2015 [ Section No. 500.8(D)(2) ]

(2) Class II Temperature.

The temperature marking specified in 500.8(C) shall be less than the ignition temperature of the specificdust to be encountered. For organic dusts that may dehydrate or carbonize, the temperature marking shallnot exceed the lower of either the ignition temperature or 165°C (329°F).

Informational Note: See NFPA 499-2013, Recommended Practice for the Classification ofCombustible Dusts and of Hazardous (Classified) Locations for Electrical Installations in ChemicalProcess Areas, for minimum ignition temperatures of specific dusts.

The ignition temperature for which equipment was approved prior to this requirement shall be assumed tobe as shown in Table 500.8(D)(2) .

Table 500.8(D)(2) Class II Temperatures

Class IIGroup

Equipment Not Subject toOverloading

Equipment (Such as Motors or Power Transformers)That May Be Overloaded

Normal Operation Abnormal Operation

°C °F °C °F °C °F

E 200 392 200 392 200 392

F 200 392 150 302 200 392

G 165 329 120 248 165 329




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Table 500.8(D)(2) and paragraph referencing the table is outdated by several code cycles asfixed limits do not apply anymore. The comparable table for gases and vapors has been removednow for several cycles.

ResponseMessage:

Public Input No. 1621-NFPA 70-2014 [Section No. 500.8(D)(2)]

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All




44 of 270 4/16/2015 11:12 AM

0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


45 of 270 4/16/2015 11:12 AM

First Revision No. 3983-NFPA 70-2015 [ Section No. 500.8(E)(2) ]

(2) Equipment Provided with Threaded Entries for Metric-Threaded Conduit or Fittings.

For equipment with metric-threaded entries, listed conduit fittings or listed cable fittings shall be used.Such entries shall be identified as being metric, or listed adapters to permit connection to conduit orNPT-threaded fittings shall be provided with the equipment and shall be used for connection to conduit orNPT-threaded fittings.

Metric-threaded entries fittings installed into explosionproof equipment shall have a class of fit of at least6g/6H and shall be made up with at least five threads fully engaged for Group C and Group D, and atleast eight threads fully engaged for Group A and Group B and wrenchtight .

Informational Note: Threading specifications for metric-threaded entries are located in ISO965-1-1998 2013 , ISO general purpose metric screw threads — Tolerances — Part 1: Principlesand basic data, and ISO 965-3-1998, ISO general purpose metric screw threads — Tolerances —Part 3: Deviations for constructional screw threads.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Section 500.9(E)(2) is not consistent with the equipment standards used to assess flame-proofequipment. The current standards require at least 5 full metric threads, regardless of gas group.Testing and field experience has demonstrated that 5 thread engagement is sufficient for all groups.References were updated.

ResponseMessage:

Public Input No. 1613-NFPA 70-2014 [Section No. 500.8(E)(2)]

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


46 of 270 4/16/2015 11:12 AM


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Regarding paragraph 2, the paragraph needs to be further edited to remove the phrase "have a class of fit of atleast 6g/6H and shall". This is because the fittings are required in the first paragraph to be listed. The class of fit isa requirement of listing. Therefore it is not needed to require gauging of the threads in the field.


The product standards for fittings and equipment already include the necessary class of fit. "shall have a class offit of at least 6g/6H and" is not required and can be deleted.

Wirfs, Mark C.

None.


47 of 270 4/16/2015 11:12 AM

First Revision No. 3987-NFPA 70-2015 [ Section No. 500.8(F) ]

(F) Optical Fiber Cables.

Where an An optical fiber cable contains conductors that are capable of carrying current , with or withoutcurrent-carrying conductors (composite optical fiber cable), the optical fiber cable shall be installed toaddress the associated fire hazard and sealed to address the associated explosion hazard in accordancewith the requirements of Article 500, 501, 502, or 503, as applicable.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The revised text clarifies that the cable needs to be sealed for explosion hazard and addressthe fire hazards, regardless if the cable contains current carrying conductors or not.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans


48 of 270 4/16/2015 11:12 AM

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


49 of 270 4/16/2015 11:12 AM

First Revision No. 3940-NFPA 70-2015 [ Sections 501.10(A)(1), 501.10(A)(2) ]

(1) General.

In Class I, Division 1 locations, the wiring methods in (a) through (e f ) shall be permitted.

(a) Threaded rigid metal conduit or threaded steel intermediate metal conduit.

Exception: Type PVC conduit, and Type RTRC conduit, and Type HDPE conduit shall be permittedwhere encased in a concrete envelope a minimum of 50 mm (2 in.) thick and provided with not less than600 mm (24 in.) of cover measured from the top of the conduit to grade. The concrete encasement shallbe permitted to be omitted where subject to the provisions of 514.8, Exception No. 2, and or 515.8(A).Threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for the last 600mm (24 in.) of the underground run to emergence or to the point of connection to the abovegroundraceway. An equipment grounding conductor shall be included to provide for electrical continuity of theraceway system and for grounding of non–current-carrying metal parts.

(b) Type MI cable terminated with fittings listed for the location. Type MI cable shall be installed andsupported in a manner to avoid tensile stress at the termination fittings.

(c) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, Type MC-HL cable listed for use inClass I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugated metallic sheath, anoverall jacket of suitable polymeric material, and a separate equipment grounding conductor(s) inaccordance with 250.122, and terminated with fittings listed for the application.

Type MC-HL cable shall be installed in accordance with the provisions of Article 330, Part II.

(d) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, Type ITC-HL cable listed for use inClass I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugated metallic sheath and anoverall jacket of suitable polymeric material, and terminated with fittings listed for the application, andinstalled in accordance with the provisions of Article 727.

(e) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall bepermitted to be installed in raceways in accordance with 501.10(A). These optical fiber cables shall besealed in accordance with 501.15.

(f) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, for applications limited to 600 volts,nominal, or less, and where protected from damage by location or a suitable guard, listed Type TC-ER-HLcable with an overall jacket and a separate equipment grounding conductor(s) in accordance with250.122 that is terminated with fittings listed for the location. Type TC-ER-HL cables shall be installed inaccordance with the provisions of Article 336.10 , including the restrictions of 336.10(7) .

(2) Flexible Connections.

Where necessary to employ flexible connections, as at motor terminals, the following shall be permitted:

(1) Flexible fittings listed for the location, or

(2) Flexible cord in accordance with the provisions of 501.140, terminated with cord connectors listed forthe location, or

(2) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, for applications limited to 600volts, nominal, or less, and where protected from damage by location or a suitable guard, listed TypeTC-ER-HL cable with an overall jacket and a separate equipment grounding conductor(s) inaccordance with 250.122 that is terminated with fittings listed for the location





50 of 270 4/16/2015 11:12 AM

Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

It was not the intent of the Panel that the exception in (1)(a) apply only in the case of a locationserving simultaneously as a dispensing facility and a bulk fuel storage facility. Therefore, the word"and" was changed to "or".

Mid span failures are extremely rare and eliminating a connection in a classified location betweenthe fixed and flexible portions of the circuit provides a further reduction in the risk of failure byeliminating that connection.

ResponseMessage:

Public Input No. 4598-NFPA 70-2014 [Section No. 501.10(A)]

Public Input No. 1250-NFPA 70-2014 [Section No. 501.10(A)(1)]

Public Input No. 1906-NFPA 70-2014 [Sections 501.10(A)(1), 501.10(A)(2)]

Ballot Results


16 Eligible Voters

1 Not Returned

10 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Wechsler, David B.


Wirfs, Mark C.

None.


Blais, Steven J.


51 of 270 4/16/2015 11:12 AM

It is not clear as to what type of connectors and/or couplings are suitable to transition from HDPE to ThreadedRigid Metal Conduit or Threaded Steel Intermediate Metal Conduit prior to emerging from the ground. Thecommittee statement indicates that “mid span failures are extremely rare”; this is in large part due to the morerobust wiring methods required for Class I, Div 1 locations. Allowing long runs of a cable wiring method with only anonmetallic jacket is not equivalent to the protection afforded by metal conduit or cable armor. Nonmetallic wiringmethods such as PVC conduit and RTRC are only allowed where encased in concrete, and NEMA would supportthe allowance of TC-ER-HL where encased in concrete.

Burns, Dave

The addition of Type HDPE conduit in this section in not part of this negative ballot. As currently written, there areno restrictions in the use of non-armored cable in Division 1 locations which could compromise the level of safetyat the location. The use of this cable in Division 1 locations is suitable provided there are appropriate restrictionsas identified in the proposed text below. The new text in (f) should be modified as follows: (f) In industrialestablishments with restricted public access, where the conditions of maintenance and supervision ensure thatonly qualified persons service the installation, for applications limited to 600 volts, nominal, or less and whereprotected from damage by location or a suitable guard, listed Type TC-ER-HL cable with an overall jacket and aseparate equipment grounding conductor(s) in accordance with 250.122 and installed in accordance with theprovisions of Article 336.10 including the restrictions of 336.10(7) shall be permitted for the following applications:(1) For applications limited to 150 volts, nominal, or less and limited to 30A circuit maximum. (2) For applicationsabove the limitations identified in (1), a metallic shield encompassing all the current carrying conductors ofsufficient material and size that will provide a reliable ground fault path that will ensure the operation of a groundfault protection device shall be required.

McBride, William E.

The unrestricted use of unarmored cable in Class I, Division 1 locations is not justified as electrical protection maybe compromised. The new text in (f) should be modified as follows: (f) In industrial establishments with restrictedpublic access, where the conditions of maintenance and supervision ensure that only qualified persons service theinstallation, for applications limited to 600 volts, nominal, or less and where protected from damage by location ora suitable guard, listed Type TC-ER-HL cable with an overall jacket and a separate equipment groundingconductor(s) in accordance with 250.122 and installed in accordance with the provisions of Article 336.10including the restrictions of 336.10(7) shall be permitted for the following applications: (1) For applications limitedto 150 volts, nominal, or less and limited to 30A circuit maximum. (2) For applications above the limitationsidentified in (1), a metallic shield encompassing all the current carrying conductors of sufficient material and sizethat will provide a reliable ground fault path that will ensure the operation of a ground fault protection device shallbe required.

Simmons, John L.

This revision permits "plug and play" installations which would indicate the purpose is to allow personnel with alower level of knowledge to connect and disconnect the instrumentation. There is no guarantee that the cable willever be supported as required in Article 336. The phrase "in industrial establishments with restricted publicaccess, where the conditions of maintenance and supervision ensure that only qualified persons service theinstallation" adds nothing to warrant an exception to the restrictions placed on these installations in the currentNEC. Why are we creating code language that is subjective and ambiguous with terms that are not defined in theNational Electrical Code? What is an “industrial establishment”? How does restricted public access make aninstallation more secure? Does the restricted access mean that fewer people will be hurt if something goeswrong? Are there some industrial locations that allow public access and others that do not? Who determines howmuch public access is allowed to comply with this relaxed requirement? Who will monitor the access? The parenttext requirements found in this section are there because hazardous gases or vapors may be present in explosivemixtures, how does restricting public access improve safety or make it less dangerous than other, non-industrial,locations? Does the phrase “where conditions of maintenance and supervision ensure that only qualified personsservice the installation” make sense? How can conditions of maintenance ensure what qualified persons do?While the NEC does provide a very loose definition of a qualified person, does the fact that a facility that isdesignated an industrial location ensure that installation and maintenance personnel are qualified to safely installelectrical equipment in hazardous locations? It is a mistake to relax any Code requirement with the belief that byloosely defining a type of facility, restricting public access and stating that some condition of maintenance willensure that qualified person will service the location. How will the fact that qualified persons are servicing theinstallation prevent a fire or explosion if there is a failure of the equipment or an accident? If a wiring application issafe for a Class I, Division 1 location in a location classified as an Industrial establishment, why isn’t theapplication safe for a non-industrial location? The whole concept of an industrial location as currently used and asproposed herein is not defined and loosely restricted. This language is confusing and unenforceable


52 of 270 4/16/2015 11:12 AM


(1) General.

In Class I, Division 2 locations, all wiring methods permitted in 501.10(A) and the following wiringmethods shall be permitted:

(1) All wiring methods permitted in 501.10(A) . Rigid metal conduit (RMC) and intermediate metalconduit (IMC) with listed threadless fittings .

(2) Electrical metallic tubing (EMT) with listed fittings.

(3) Enclosed gasketed busways and enclosed gasketed wireways.

(4) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, includinginstallation in cable tray systems. The cable shall be terminated with listed fittings.

(5) Type ITC and Type ITC-ER cable as permitted in 727.4 and terminated with listed fittings.

(6) Type MC, MV, TC, or TC-ER cable, including installation in cable tray systems. The cable shall beterminated with listed fittings.

(7) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation and where metallic conduitdoes not provide sufficient corrosion resistance, listed reinforced thermosetting resin conduit (RTRC),factory elbows, and associated fittings, all marked with the suffix -XW, and Schedule 80 PVC conduit,factory elbows, and associated fittings shall be permitted.

(8) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall bepermitted to be installed in cable trays or any other raceway in accordance with 501.10(B). Opticalfiber cables shall be sealed in accordance with 501.15.

(9) Cablebus.

Where seals are required for boundary conditions as defined in 501.15(A)(4) , the Division 1 wiring methodshall extend into the Division 2 area to the seal, which shall be located on the Division 2 side of theDivision 1–Division 2 boundary.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Threadless fittings for RMC and IMC, along with the addition of EMT, provide an appropriate levelof safety for a Class I, Division 2 location. Sealing with threaded connections at the Class I,Division 2 boundary is already addressed by 501.15(B)(2).

Cablebus per Article 370 provides a level of safety equivalent to the other wiring methodspermitted for the identified locations.

ResponseMessage:



53 of 270 4/16/2015 11:12 AM


Ballot Results


16 Eligible Voters

1 Not Returned

9 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan


Wechsler, David B.

There has been no data supplied to support EMT’s use in Class I hazardous classified locations and merelysuggesting that other methods may or may not offer equivalent protection is highly subjective. We stronglysuggest that CMP14 review this application in the comment stage and consider what data, if any, supports addingthis use in Class I, hazardous classified locations. Note: Correct spelling of Metallic

Wirfs, Mark C.

None.


Burns, Dave

The wiring method "EMT" is not equivalent to any existing approved wiring methods for use in Class I, Division 2locations. There were no adequate substantiations provided with this proposal. There is no evidence to justify thelowering of standards for wiring practices in Class I, Division 2 areas. There were no restrictions for fittings; thismethod would not provide the positive grounding provisions in order to provide a reasonable degree of safety inhazardous locations. An application of a seal fitting with this material may not comply with the requirements ofArticle 358.12. The physical properties of this method is not sufficient to be installed in hazardous location. Thewall thickness of EMT is typically less than half on the other wiring methods identified in this section. EMT conduitinstalled in Division 2 public areas such as garages, gas stations, hangers, etc. could be subject to physicaldamage and result in an open ignition source in a hazardous location. This use of this wiring method in Class I,Division 2 locations will lower the current standard of safety.

Kines, Haywood

The use of Electrical Metallic Tubing in any Class 1 Division II location such as repair garages where there arepotential hazards or accidental damage to the raceways that creates a potential safety hazard where the racewayis used as the equipment grounding means. Arching from fault currents due to damaged tubing or fittings used onthis type of raceway could be a safety hazard due to the types of liquids or gases present in the air. The approvalfor use in Industrial establishments with restrict public access and conditions of maintenance and supervision wasensued by qualified personnel only, would be a lower hazardous use of EMT and its listed fittings.


54 of 270 4/16/2015 11:12 AM

McBride, William E.

The wiring method "EMT" is not equivalent to existing approved wiring methods for use in Class I, Division 2locations. There were no adequate substantiations provided with this proposal. There is no evidence to justify thelowering of standards for wiring practices in Class I, Division 2 areas. There were no restrictions for fittings; thismethod would not provide the positive grounding provisions in order to provide a reasonable degree of safety inhazardous locations. An application of a seal fitting with this material would not comply with the requirements ofArticle 358.12. The physical properties of this method is not sufficient to be installed in hazardous location Thewall thickness of EMT is typically less than half on the other wiring methods identified in this section. This use ofthis wiring method in Class I, Division 2 locations will lower the standard of safety.

Simmons, John L.

A Class I, Division 2 location is just an accident or equipment malfunction from being a Class I, Division I location.This first revision will relax the wiring methods permitted in Class I, Division 2 locations without providing onepiece of technical data to prove that the use of EMT and /or threadless fittings provides a safe installation in theselocations. This could prove to be dangerous.


55 of 270 4/16/2015 11:12 AM


(1) Entering Enclosures.

Each conduit entry into an explosionproof enclosure shall have a conduit seal where either of the followingconditions applies:

(1) The enclosure contains apparatus, such as switches, circuit breakers, fuses, relays, or resistors, thatmay produce arcs, sparks, or temperatures that exceed 80 percent of the autoignition temperature, indegrees Celsius, of the gas or vapor involved in normal operation.

Exception: Seals shall not be required for conduit entering an enclosure under any one of thefollowing conditions:

a. The switch, circuit breaker, fuse, relay, or resistor is enclosed within a chamber hermeticallysealed against the entrance of gases or vapors.

b. The switch, circuit breaker, fuse, relay, or resistor is immersed in oil in accordance with501.115(B)(1)(2).

c. The switch, circuit breaker, fuse, relay, or resistor is enclosed within a factory-sealedexplosionproof chamber located within the enclosure, identified for the location, and marked“factory sealed” or equivalent.

d. The switch, circuit breaker, fuse, relay, or resistor is part of a nonincendive circuit.

(2) The entry is metric designator 53 (trade size 2) or larger, and the enclosure contains terminals,splices, or taps.

Factory-sealed enclosures shall not be considered to serve as a seal for another adjacent explosionproofenclosure that is required to have a conduit seal.

Conduit seals shall be installed within 450 mm (18 in.) from the enclosure or as required by the enclosuremarking . Only explosionproof unions, couplings, reducers, elbows, and capped elbows, and conduitbodies similar to L, T, and Cross types that are not larger than the trade size of the conduit shall bepermitted between the sealing fitting and the explosionproof enclosure.




Street Address:

City:

State:

Zip:

Submittal Date: Thu Jan 15 08:38:50 EST 2015

Committee Statement

CommitteeStatement:

This revision correlates with the revision to 501.15(D)(1). Some explosionproof enclosures musthave the seal located less than 18 in. away and are so marked. It was not the intent of this sectionto override those restrictions. Conduit bodies were removed from the list in (2) because they shouldnot be allowed in this application due to the increased volume in the raceway system.

ResponseMessage:

Ballot Results



56 of 270 4/16/2015 11:12 AM

16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


57 of 270 4/16/2015 11:12 AM

First Revision No. 3973-NFPA 70-2015 [ Section No. 501.15(D)(1) ]

(1) At Terminations.

Cables shall be sealed with sealing fittings that comply with 501.15(C) at all terminations. Type MC-HLcables with a gas/vaportight continuous corrugated metallic sheath and an overall jacket of suitablepolymeric material shall be sealed with a listed fitting after the jacket and any other covering have beenremoved so that the sealing compound can surround each individual insulated conductor in such amanner as to minimize the passage of gases and vapors.

Seals for cables entering enclosures shall be installed within 450 mm (18 in.) of the enclosure or asrequired by the enclosure marking. Only explosionproof unions, couplings, reducers, elbows, and cappedelbows that are not larger than the trade size of the enclosure entry shall be permitted between thesealing fitting and the enclosure.

Exception: Shielded cables and twisted pair cables shall not require the removal of the shielding materialor separation of the twisted pairs, provided the termination is sealed by an approved means to minimizethe entrance of gases or vapors and prevent propagation of flame into the cable core.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The revised text addresses the need for other types of explosionproof fittings that can be safelyutilized between a cable seal and an enclosure. Some explosionproof enclosures must have theseal located less than 18 in. away and are so marked.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


58 of 270 4/16/2015 11:12 AM


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


59 of 270 4/16/2015 11:12 AM


(3) Cables Capable of Transmitting Gases or Vapors.

Cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cablecore shall not be required to be sealed except as required in 501.15(E)(1) , unless the cable is attachedto process equipment or devices that may cause a pressure in excess of 1500 pascals (6 in. of water) tobe exerted at a cable end, in which case a seal, a barrier, or other means shall be provided to preventmigration of flammables into an unclassified location.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The revised text provides clarification that these cables are only required to be sealed whenrequired by 501.15(E)(1) or when these cables are attached to process equipment or devices thatmay cause a pressure in excess of 1500 pascals (6 in. of water). This revision correlates with therequirements in 505.15(C)(2) for Class I, Zone 2 applications.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


60 of 270 4/16/2015 11:12 AM


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Ankele, Donald W.

Retain the wording of the 2014 NEC. This is because the proposed revision could permit the passage of gassesor vapors into an unclassified area. The 2014 wording was revised such that the end of the cable be sealed inaccordance with the sealing criteria in 501.15(E)(1) in order to seal the end of the cable because a cable with agas tight sheath is no required to be sealed at the boundary.


61 of 270 4/16/2015 11:12 AM


(A) Class I, Division 1.

In Class I, Division 1 locations, meters, instruments, and relays, including kilowatt-hour meters, instrumenttransformers, resistors, rectifiers, and thermionic tubes, shall comply with 501.105(A)(1) and (A)(2).

(1) Enclosures.

shall be provided with enclosures Enclosures that are identified for Class I, Division 1 locations shall beprovided . Enclosures for Class I, Division 1 locations include explosionproof enclosures and purged andpressurized enclosures.

Informational Note: See NFPA 496-2013, Standard for Purged and Pressurized Enclosures forElectrical Equipment.

(2) Connections.

To facilitate replacement in industrial establishments with restricted public access, where the conditionsof maintenance and supervision ensure that only qualified persons service the installation, and wherethe cable is not subject to physical damage, meters, instruments, and relays shall be permitted to beconnected through Type TC-ER-HL cable by means of attachment plugs and receptacles, provided thatall of the following conditions apply:

(1) Attachment plug and receptacle is listed for use in Class I, Division 1 locations and for use withTC-ER-HL cable.

(2) The attachment plug and receptacle is interlocked mechanically or electrically, or otherwisedesigned so that they cannot be separated when the contacts are energized and the contactscannot be energized when the plug and socket outlet are separated.

(3) Type TC-ER-HL cable is listed for use in Class I, Division 1 locations.

(4) Type TC-ER-HL cable is installed in accordance with the provisions of Article 336 , including therestrictions of 336.10(7) .

(5) Only necessary receptacles are provided.

Supplemental Information

File Name Description

501.105-A_3969_BC.docx




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Type TC-ER-HL is added as a permissible wiring method for the connection of meters,instruments, and relays in a Class I, Division 1 location. Notation to the Article 336, including therestrictions of Section 336.10(7), is necessary to address Type TC-ER-HL.


62 of 270 4/16/2015 11:12 AM

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Wechsler, David B.


Wirfs, Mark C.

None.


Burns, Dave

Standard AC power plugs and receptacles should not be used for instrument connections. This may causeinstrument malfunctions as the shielded circuits will not be continuous and promote possible confusion of powerand instrumentation receptacles leading to instruments being exposed to excessive voltage resulting in a possiblesource of ignition in a hazardous location. Item (5) is recommended to be deleted as it provides nothing of value.Edit text as below: (2) Connections. To facilitate replacement in industrial establishments with restricted publicaccess, where the conditions of maintenance and supervision ensure that only qualified persons service theinstallation, and where the cable is not subject to physical damage; meters, instruments and relays shall bepermitted to be connected through Type TC-ER-HL cable, by means of attachment plugs and receptaclesspecifically identified for instrumentation, provided that all of the following conditions apply: (1) Attachment plugand receptacle is listed for use in Class I, Division 1 locations and for use with TC-ER-HL cable and individualcircuits limited to 3 amperes. (2) The attachment plug and receptacle is interlocked mechanically, or electrically, orotherwise designed so that they cannot be separated when the contacts are energized and the contacts cannot beenergized when the plug and socket outlet are separated. (3) Type TC-ER-HL cable is listed for use in Class I,Division 1 locations. (4) Type TC-ER-HL cable is installed in accordance with the provisions of Article 336,including the restrictions of 336.10(7).

Simmons, John L.

This revision permits "plug and play" installations which would indicate the purpose is to allow personnel with a


63 of 270 4/16/2015 11:12 AM

lower level of knowledge to connect and disconnect the instrumentation. There is no guarantee that the cable willever be supported as required in Article 336. The phrase "in industrial establishments with restricted publicaccess, where the conditions of maintenance and supervision ensure that only qualified persons service theinstallation" adds nothing to warrant an exception to the restrictions placed on these installations in the currentNEC. Why are we creating code language that is subjective and ambiguous with terms that are not defined in theNational Electrical Code? What is an “industrial establishment”? How does restricted public access make aninstallation more secure? Does the restricted access mean that fewer people will be hurt if something goeswrong? Are there some industrial locations that allow public access and others that do not? Who determines howmuch public access is allowed to comply with this relaxed requirement? Who will monitor the access? The parenttext requirements found in this section are there because hazardous gases or vapors may be present in explosivemixtures, how does restricting public access improve safety or make it less dangerous than other, non-industrial,locations? Does the phrase “where conditions of maintenance and supervision ensure that only qualified personsservice the installation” make sense? How can conditions of maintenance ensure what qualified persons do?While the NEC does provide a very loose definition of a qualified person, does the fact that a facility that isdesignated an industrial location ensure that installation and maintenance personnel are qualified to safely installelectrical equipment in hazardous locations? It is a mistake to relax any Code requirement with the belief that byloosely defining a type of facility, restricting public access and stating that some condition of maintenance willensure that qualified person will service the location. How will the fact that qualified persons are servicing theinstallation prevent a fire or explosion if there is a failure of the equipment or an accident? If a wiring application issafe for a Class I, Division 1 location in a location classified as an Industrial establishment, why isn’t theapplication safe for a non-industrial location? The whole concept of an industrial location as currently used and asproposed herein is not defined and loosely restricted. This language is confusing and unenforceable.


64 of 270 4/16/2015 11:12 AM

First Revision No. 3971-NFPA 70-2015 [ Sections 501.105(B)(1), 501.105(B)(2),

501.105(B)(3), 501.1... ]

(1) General-Purpose Assemblies.

Where an assembly is made up of components for which general-purpose enclosures are acceptable asprovided in 501.105(B)(1), (B)(2), and (B)(3), a single general-purpose enclosure shall be acceptable forthe assembly. Where such an assembly includes any of the equipment described in 501.105(B)(1) ,501.105(B)(2), and 501.105(B)(3) , the maximum obtainable surface temperature of any component ofthe assembly that exceeds 100°C shall be clearly and permanently indicated on the outside of theenclosure. Alternatively, equipment shall be permitted to be marked to indicate the temperature class forwhich it is suitable, using the temperature class (T Code) of Table 500.8(C).

(2) Contacts.

Switches, circuit breakers, and make-and-break contacts of pushbuttons, relays, alarm bells, and hornsshall have enclosures identified for Class I, Division 1 locations in accordance with 501.105(A).

Exception: General-purpose enclosures shall be permitted if current-interrupting contacts comply withone of the following:

(1) Are immersed in oil

(2) Are enclosed within a chamber that is hermetically sealed against the entrance of gases or vapors

(3) Are in nonincendive circuits

(4) Are listed for Division 2

(3) Resistors and Similar Equipment.

Resistors, resistance devices, thermionic tubes, rectifiers, and similar equipment that are used in or inconnection with meters, instruments, and relays shall comply with 501.105(A).

Exception: General-purpose-type enclosures shall be permitted if such equipment is withoutmake-and-break or sliding contacts [other than as provided in 501.105(B)(2)501.105(B)(2) 501.105(B)(2) 501.105(B)(1) ] and if the marked maximum operating temperature of any exposed surface will notexceed 80 percent of the autoignition temperature in degrees Celsius of the gas or vapor involved or hasbeen tested and found incapable of igniting the gas or vapor. This exception shall not apply tothermionic tubes.

(4) Without Make-or-Break Contacts.

Transformer windings, impedance coils, solenoids, and other windings that do not incorporate sliding ormake-or-break contacts shall be provided with enclosures. General-purpose-type enclosures shall bepermitted.

(5) Fuses.

Where general-purpose enclosures are permitted in 501.105(B)(2)501.105(B)(2) 501.105(B)(2) 501.105(B)(1) through (B)(4), fuses for overcurrent protection of instrument circuits not subject tooverloading in normal use shall be permitted to be mounted in general-purpose enclosures if each suchfuse is preceded by a switch complying with 501.105(B)(2)501.105(B)(2) 501.105(B)(2) 501.105(B)(1) .




Street Address:

City:

State:

Zip:


Committee Statement


65 of 270 4/16/2015 11:12 AM

CommitteeStatement:

The requirement for marking the maximum attainable surface temperature of any component shouldalso apply to enclosures that contain switches, circuit breakers, and make-and-break contacts orwhere transformer windings, impedance coils, solenoids, and other windings are contained within theenclosure. The section was further revised to clarify when the 80% rule of the AIT applies and whenthe Temperature Classification can be used. Also added was the exclusion to the markingrequirement for surface temperatures that are 100°C or less.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Although not indicated by legislative text or other means such as the committee statement, the content of (B) (1),(2), (3) and (4) have been re-ordered, making the references within them now incorrect. Keep the original order ofcontent as is currently published.


The sections have been renumbered and the references to those sections are now incorrect. (1) was (4), (2) was(1), (3) as (2), (4) was (3). (5) and (6) remained numbered as in the 2014 NEC.

Wirfs, Mark C.

None.


66 of 270 4/16/2015 11:12 AM


(6) Connections.

To facilitate replacements, process control instruments shall be permitted to be connected through flexiblecord, listed Type TC-ER cable, or Type TC-ER-HL cable, by means of attachment plug, and receptacle,provided that all of the following conditions apply:

(1) Attachment plug and receptacle are listed for use in Class I, Division 2 locations and for use withflexible cords, Type TC-ER cable or Type TC-ER-HL cable as applicable, and shall be of the lockingand grounding type.

Exception: A Class I, Division 2 listing is not required if the circuit is nonincendive field wiring.

(2) A Unless the attachment plug and receptacle are interlocked mechanically or electrically, orotherwise designed so that they cannot be separated when the contacts are energized and thecontacts cannot be energized when the plug and socket outlet are separated, a switch complyingwith 501.105(B)(2)501.105(B)(2) 501.105(B)(2) 501.105(B)(1) is provided so that the attachmentplug or receptacle is not depended on to interrupt current.

Exception: The switch is not required if the circuit is nonincendive field wiring.

(2) The current does not exceed 3 amperes at 120 volts, nominal.

(3) The power-supply flexible cord does not exceed 900 mm (3 ft), and is of a type listed for extra-hardusage or for hard usage if protected by location, and is supplied through an attachment plug andreceptacle of the locking and grounding type if applicable .

(4) Type TC-ER cable or Type TC-ER-HL cable is installed in accordance with the provisions of Article336 , including the restrictions of 336.10(7) , if applicable.


(6) The Unless the attachment plug and receptacle are interlocked mechanically or electrically, orotherwise designed so that they cannot be separated when the contacts are energized and thecontacts cannot be energized when the plug and socket outlet are separated, the instrumentationreceptacle carries a label warning against plugging or unplugging under load.



501.105-B-6_3967_BC.docx




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Types TC-ER and TC-ER-HL are added as permissible wiring methods for the connection ofprocess control instruments in a Class I, Division 2 location. In addition, the requirements forflexible cords are clarified. Notation to the Article 336, including the restrictions of Section336.10(7), is necessary to address Type TC-ER-HL.


67 of 270 4/16/2015 11:12 AM

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

10 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Wechsler, David B.


Ankele, Donald W.

Add Type TC cable to (6)(1) as it is a permitted Div. 2 wiring method.

Wirfs, Mark C.

None.


Burns, Dave

This section is for instruments and relays and the current restriction for 3 ampere circuits should be maintained.Delete "if applicable" in (4), delete text in (5) as it adds no value, and delete (6) as the label exception introducesunnecessary hazards in a Division 2 locations. The section is proposed to read as follows: (B) Class I, Division 2.(6) Connections. To facilitate replacements, process control instruments shall be permitted to be connectedthrough flexible cord, listed Type TC-ER cable or Type TC-ER-HL cable, by means of attachment plug, andreceptacle specifically identified for instrumentation, provided that all of the following conditions apply: (1)Attachment plug and receptacle is listed for use in Class I, Division 2 locations and for use with flexible cords,Type TC-ER cable or Type TC-ER-HL cable as applicable, and shall be of the locking and grounding type.Exception: A Class I, Division 2 listing is not required if the circuit is nonincendive field wiring. (2) Unless theattachment plug and receptacle are interlocked mechanically, or electrically, or otherwise designed so that theycannot be separated when the contacts are energized and the contacts cannot be energized when the plug andsocket outlet are separated, a switch complying with 501.105(B) (2) is provided so that the attachment plug orreceptacle is not depended on to interrupt current. Exception: The switch is not required if the circuit isnonincendive field wiring. (3) The current does not exceed 3 amperes at 120 volts, nominal. (4) The flexible corddoes not exceed 900 mm (3 ft), is of a type listed for extra-hard usage or for hard usage if protected by location.(5) Type TC-ER cable or Type TC-ER-HL cable is installed in accordance with the provisions of Article 336,including the restrictions of 336.10(7), if applicable.


68 of 270 4/16/2015 11:12 AM

McBride, William E.

This section is for instruments and relays and the current restriction for 3 Amp circuit should be maintained.Delete "if applicable" in (4), delete text in (5) as it adds no value, and delete (6) as the label exception introducesunnecessary hazards in a Division 2 location.

Simmons, John L.

Section 501.105(B)(6) is not positive code language, it is a disguised exception. Requiring a label that does notreduce or eliminate the hazard in a Class 1, Division 2 location might not prevent a worker from plugging orunplugging equipment under load. There is always the possibility that an explosive concentration can exist andsomeone may unplug an instrument under load. The purpose of the National Electrical Code is to protect personsand property from the hazard arising from the use of electricity, this language does not provide for that.501.105(B)(6) should be deleted.


69 of 270 4/16/2015 11:12 AM


(A) Class I, Division 1.

In Class I, Division 1 locations, motors, generators, and other rotating electrical machinery shall be one ofthe following:

(1) Identified for Class I, Division 1 locations

(2) Of the totally enclosed type supplied with positive-pressure ventilation from a source of clean air withdischarge to a safe area, so arranged to prevent energizing of the machine until ventilation has beenestablished and the enclosure has been purged with at least 10 volumes of air, and also arranged toautomatically de-energize the equipment when the air supply fails

(3) Of the totally enclosed inert gas–filled type supplied with a suitable reliable source of inert gas forpressurizing the enclosure, with devices provided to ensure a positive pressure in the enclosure andarranged to automatically de-energize the equipment when the gas supply fails

(4) Of For machines that are for use only in industrial establishments with restricted public access,where the conditions of maintenance and supervision ensure that only qualified persons service theinstallation, the machine is permitted to be of a type designed to be submerged in a liquid that isflammable only when vaporized and mixed with air, or in a gas or vapor at a pressure greater thanatmospheric and that is flammable only when mixed with air; and the machine is so arranged toprevent energizing it until it has been purged with the liquid or gas to exclude air, and also arrangedto automatically de-energize the equipment when the supply of liquid or gas or vapor fails or thepressure is reduced to atmospheric

Totally enclosed motors of the types specified in 501.125(A)(2) or (A)(3) shall have no external surfacewith an operating temperature in degrees Celsius in excess of 80 percent of the autoignition temperatureof the gas or vapor involved. Appropriate devices shall be provided to detect and automaticallyde-energize the motor or provide an adequate alarm if there is any increase in temperature of the motorbeyond designed limits. Auxiliary equipment shall be of a type identified for the location in which it isinstalled.



501.125-A_3966_BC.docx




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Submersible machines and those protected by a flammable atmosphere maintained above theUFL require operation and maintenance by trained persons, and therefore should only be used inindustrial establishments with restricted public access.

ResponseMessage:


70 of 270 4/16/2015 11:12 AM


Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Wechsler, David B.


Wirfs, Mark C.

None.


Simmons, John L.

I understand the proposed restriction for this application and agree that the associated danger warrant eitherdoing away with the practice or adding Code language that ensures the safety of the installation. The proposedlanguage is subjective and ambiguous with terms that are not defined in the National Electrical Code. What is an“industrial establishment”? Is an industrial establishment created when the public is restricted and there are sometype of conditions mandating that only qualified persons service the equipment? Does the fact that we classify afacility as being an industrial establishment mean that maintenance and repair operations are better than anon-industrial establishment? What are the guidelines for an industrial establishment and who is charged withinensuring that the facility remains in compliance? What is intended when the language “restricted public access” isused? Does it mean that the public should be kept out of the facility or do members of the public have to beaccompanied, if the visit the facility? How does this provide a safer environment? Does the phrase “whereconditions of maintenance and supervision ensure that only qualified persons service the installation” makesense? How can conditions of maintenance ensure that qualified persons service the facility? If an installation isdangerous under any circumstance, then it is the responsibility of the NEC to prohibit the practice for all facilitiesto ensure the safety of everyone involved. Fire and explosions cannot be prevented merely by creating anindustrial establishment category


71 of 270 4/16/2015 11:12 AM


(B) Class I, Division 2.

In Class I, Division 2 locations, motors, generators, and other rotating electrical machinery in which areemployed shall comply with the following:

(1) Be identified for Class I, Division 2 locations, or

(2) shall be identified for Class I, Division 1 locations, unless such sliding contacts, Be identified forClass I, Division 1 locations where sliding contacts, centrifugal or other types of switchingmechanism (including motor overcurrent, overloading, and overtemperature devices), or integralresistance devices, either while starting or while running, are employed, or

(3) Be open or nonexplosionproof enclosed motors, such as squirrel-cage induction motors withoutbrushes, switching mechanisms, and resistance devices are provided with enclosures identified forClass I, Division 2 locations in accordance with 501.105(B) or similar arc-producing devices that arenot identified for use in a Class I, Division 2 location .

(4) The exposed surface of space heaters used to prevent condensation of moisture during shutdownperiods shall not exceed 80 percent of the autoignition temperature in degrees Celsius of the gas orvapor involved when operated at rated voltage, and the maximum space heater surface temperature[based on a 40°C or higher marked ambient] shall be permanently marked on a visible nameplatemounted on the motor. Otherwise, space heaters shall be identified for Class I, Division 2 locations.In Class I, Division 2 locations, the installation of open or nonexplosionproof enclosed motors, suchas squirrel-cage induction motors without brushes, switching mechanisms, or similar arc-producingdevices that are not identified for use in a Class I, Division 2 location, shall be permitted.

(5) A sliding contact shaft bonding device used for the purpose of maintaining the rotor at groundpotential, shall be permitted where the potential discharge energy is determined to be nonincendivefor the application. The shaft bonding device shall be permitted to be installed on the inside or theoutside of the motor.

Informational Note No. 1: It is important to consider the temperature of internal and externalsurfaces that may be exposed to the flammable atmosphere.

Informational Note No. 2: It is important to consider the risk of ignition due to currents arcing acrossdiscontinuities and overheating of parts in multisection enclosures of large motors and generators.Such motors and generators may need equipotential bonding jumpers across joints in theenclosure and from enclosure to ground. Where the presence of ignitible gases or vapors issuspected, clean-air purging may be needed immediately prior to and during start-up periods.

Informational Note No. 3: For further information on the application of electric motors in Class I,Division 2 hazardous (classified) locations, see IEEE 1349-2011, IEEE Guide for the Application ofElectric Motors in Class I, Division 2 and Class I, Zone 2 Hazardous (Classified) Locations.

Informational Note No. 4: Reciprocating engine-driven generators, compressors, and otherequipment installed in Class I, Division 2 locations may present a risk of ignition of flammablematerials associated with fuel, starting, compression, and so forth, due to inadvertent release orequipment malfunction by the engine ignition system and controls. For further information on therequirements for ignition systems for reciprocating engines installed in Class I, Division 2hazardous (classified) locations, see ANSI/ISA-12.20.01-2009 UL 122001-2004 , GeneralRequirements for Electrical Ignition Systems for Internal Combustion Engines in Class I, Division 2or Zone 2, Hazardous (Classified) Locations.

Informational Note No. 5: For details of the evaluation process to determine incendivity, referto Annex A and Figure A1 of UL SU1836, Outline of Investigation for Electric Motors andGenerators for Use in Class I, Division 2, Class I, Zone 2, Class II, Division 2 and Zone 22Hazardous (Classified) Locations .




72 of 270 4/16/2015 11:12 AM


Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The 501.125(B) format is revised to follow the format of 501.125(A) to create uniformity. The newitem 5) permits a shaft bonding device to be used on inverter-fed motors for the purpose ofmaintaining the rotor at ground potential to reduce bearing failure due to arcing. Informational noteno. 5 was added to provide guidance on application of shaft bonding devices.

The electrical ignition systems document for internal combustion engines located in hazardousareas has been renumbered.

ResponseMessage:



Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.


Wirfs, Mark C.

None.


73 of 270 4/16/2015 11:12 AM


Wechsler, David B.

Nothing in the NEC prohibits a shaft bonding device to be used on inverter-fed motors. There is notdocumentation to suggest that all inverter-fed motors require this bond. No standard has been supplied to definehow the potential discharge energy would be ‘nonincendive’. The term ‘application’ for which the requirement ofnonincendive is not identified.


74 of 270 4/16/2015 11:12 AM


(B) Attachment Plugs.

Attachment plugs shall be of the type providing for connection to the equipment grounding conductor of apermitted flexible cord or cable and shall be identified for the location.

Exception: Receptacles and attachment plugs as provided in 501.105(B)(6).




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Type TC-ER-HL cable is a permissible wiring method in Class I, Division 1 locations, thereforeSection 501.145(B) should be expanded to include the term “cable” along with “cord”. Theexception was deleted, as the reference was incorrect and the original intent was unclear. Section501.10 Wiring Methods still apply to all Article 501 sections.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Burns, Dave

Jones, Robert A.

Kines, Haywood



75 of 270 4/16/2015 11:12 AM

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Blais, Steven J.

Type TC-ER-HL is not a flexible cord or flexible cable. Flexible cords and flexible cables are covered in Article400.

Wirfs, Mark C.

None.


76 of 270 4/16/2015 11:12 AM


(1) General.

In Class II, Division 1 locations, the wiring methods in (1) through (4 5 ) shall be permitted:

(1) Threaded rigid metal conduit, or threaded steel intermediate metal conduit.

(2) Type MI cable with termination fittings listed for the location. Type MI cable shall be installed andsupported in a manner to avoid tensile stress at the termination fittings.

(3) In industrial establishments with limited public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, Type MC-HL cable, listed foruse in Class II, Division 1 locations, with a gas/vaportight continuous corrugated metallic sheath, anoverall jacket of suitable polymeric material, a separate equipment grounding conductor(s) inaccordance with 250.122, and provided with termination fittings listed for the location, shall bepermitted.

(4) Optical fiber cables cable Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shallbe permitted to be installed in raceways in accordance with 502.10(A). Optical fiber cables shall besealed in accordance with 502.15.

(5) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, listed Type ITC-HL cable witha gas/vaportight continuous corrugated metallic sheath and an overall jacket of suitable polymericmaterial, and terminated with fittings listed for the application, and installed in accordance with theprovisions of Article 727 .




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: ITC-HL provides an appropriate level of safety for a Class II, Division 1 location.

Response Message:


Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention


77 of 270 4/16/2015 11:12 AM

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Wechsler, David B.


Wirfs, Mark C.

None.


Simmons, John L.

This revision permits "plug and play" installations which would indicate the purpose is to allow personnel with alower level of knowledge to connect and disconnect the instrumentation. There is no guarantee that the cable willever be supported as required in Article 336. The phrase "in industrial establishments with restricted publicaccess, where the conditions of maintenance and supervision ensure that only qualified persons service theinstallation" adds nothing to warrant an exception to the restrictions placed on these installations in the currentNEC. Why are we creating code language that is subjective and ambiguous with terms that are not defined in theNational Electrical Code? What is an “industrial establishment”? How does restricted public access make aninstallation more secure? Does the restricted access mean that fewer people will be hurt if something goeswrong? Are there some industrial locations that allow public access and others that do not? Who determines howmuch public access is allowed to comply with this relaxed requirement? Who will monitor the access? The parenttext requirements found in this section are there because hazardous gases or vapors may be present in explosivemixtures, how does restricting public access improve safety or make it less dangerous than other, non-industrial,locations? Does the phrase “where conditions of maintenance and supervision ensure that only qualified personsservice the installation” make sense? How can conditions of maintenance ensure what qualified persons do?While the NEC does provide a very loose definition of a qualified person, does the fact that a facility that isdesignated an industrial location ensure that installation and maintenance personnel are qualified to safely installelectrical equipment in hazardous locations? It is a mistake to relax any Code requirement with the belief that byloosely defining a type of facility, restricting public access and stating that some condition of maintenance willensure that qualified person will service the location. How will the fact that qualified persons are servicing theinstallation prevent a fire or explosion if there is a failure of the equipment or an accident? If a wiring application issafe for a Class I, Division 1 location in a location classified as an Industrial establishment, why isn’t theapplication safe for a non-industrial location? The whole concept of an industrial location as currently used and asproposed herein is not defined and loosely restricted. This language is confusing and unenforceable.


78 of 270 4/16/2015 11:12 AM


(1) General.

In Class II, Division 2 locations, the following wiring methods shall be permitted:

(1) All wiring methods permitted in 502.10(A) .

(2) Rigid metal conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways.

(3) Type MC or MI cable with listed termination fittings.



(6) Type MC, MI, MV, TC, or TC-ER cable installed in ladder, ventilated trough, or ventilated channelcable trays in a single layer, with a space not less than the larger cable diameter between the twoadjacent cables, shall be the wiring method employed.

Exception to (6): Type MC cable listed for use in Class II, Division 1 locations shall be permitted tobe installed without the spacings required by (6).

(7) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation and where metallic conduitdoes not provide sufficient corrosion resistance, reinforced thermosetting resin conduit (RTRC)factory elbows, and associated fittings, all marked with suffix -XW, and Schedule 80 PVC conduit,factory elbows and associated fittings shall be permitted.

(8) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall bepermitted to be installed in cable trays or any other raceway in accordance with 502.10(B). Opticalfiber cables shall be sealed in accordance with 502.15.

(9) Cablebus.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

MV and TC-ER provide an appropriate level of safety for a Class II, Division 2 location. Cablebusper Article 370 provides a level of safety equivalent to the other wiring methods permitted for theidentified locations.

ResponseMessage:




Ballot Results


79 of 270 4/16/2015 11:12 AM


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


80 of 270 4/16/2015 11:12 AM


(1) General.

In Class III, Division 1 locations, the wiring method shall be in accordance with (1) through (4) (5) :

(1) Rigid metal conduit, Type PVC conduit, Type RTRC conduit, intermediate metal conduit, electricalmetallic tubing, dusttight wireways, or Type MC or MI cable with listed termination fittings.



(4) Type MC, MI, MV, TC, or TC-ER cable installed in ladder, ventilated trough, or ventilated channelcable trays in a single layer, with a space not less than the larger cable diameter between the twoadjacent cables, shall be the wiring method employed. The cable shall be terminated with listedfittings.

Exception to (4): Type MC cable listed for use in Class II, Division 1 locations shall be permitted tobe installed without the spacings required by 503.10(A)(1)(4) .

(5) Cablebus.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

MV provides an appropriate level of safety for a Class III, Division 1 location. Cablebus perArticle 370 provides a level of safety equivalent to the other wiring methods permitted for theidentified locations.

ResponseMessage:



Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention


81 of 270 4/16/2015 11:12 AM

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Burns, Dave

The use of non-shielded and non-metallic jacked MV cable should not be allowed in Class III, Division 1 locations.The substantiation for this proposal provided by a cable manufacturer "MV cable is allowed for Class I, Division 2locations and should be allowed in Class III, Division 1 and 2 locations, as well" is not sufficient to lower thecurrent standard of safety. Type MV Cable should have a more robust jacket if it is to be allowed in a Division 1locations.

McBride, William E.

The use of non-metallic jacked MV cable should not be allowed in Class III, Division 1 locations. Thesubstantiation for this proposal provided by a cable manufacturer "MV cable is allowed for Class I, Division 2locations and should be allowed in Class III, Division 1 and 2 locations, as well" in not sufficient to lower thecurrent standard of safety. Type MV Cable should have a more robust jacket if it is to be allowed in a Division 1location; possibly a MV-ER-HL that has increased crush and impact requirements.


82 of 270 4/16/2015 11:12 AM

First Revision No. 3992-NFPA 70-2015 [ Section No. 504.1 ]

504.1 Scope.

This article covers the installation of intrinsically safe (I.S.) apparatus, wiring, and systems for Class I, II,and III locations Articles 500 through 516 .

Informational Note: For further information, see ANSI/ISA-RP 12.06.01-2003, RecommendedPractice for Wiring Methods for Hazardous (Classified) Locations Instrumentation — Part 1:Intrinsic Safety.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The Scope statement has been amended to resolve the scope conflict for Article 506 andother potentially affected articles.

ResponseMessage:



Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


83 of 270 4/16/2015 11:12 AM

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


84 of 270 4/16/2015 11:12 AM

First Revision No. 3919-NFPA 70-2015 [ Definition: Associated Apparatus. ]

Associated Apparatus [as applied to Hazardous (Classified) Locations] .

Apparatus in which the circuits are not necessarily intrinsically safe themselves but that affects the energyin the intrinsically safe circuits and is relied on to maintain intrinsic safety. Such apparatus is one of thefollowing:

(1) Electrical apparatus that has an alternative type of protection for use in the appropriate hazardous(classified) location

(2) Electrical apparatus not so protected that shall not be used within a hazardous (classified) location

Informational Note No. 1: Associated apparatus has identified intrinsically safe connections forintrinsically safe apparatus and also may have connections for nonintrinsically safe apparatus.

Informational Note No. 2: An example of associated apparatus is an intrinsic safety barrier, which isa network designed to limit the energy (voltage and current) available to the protected circuit in thehazardous (classified) location, under specified fault conditions.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Associated Apparatus appears in Articles 500,504, 505, and 506. The definition iscurrently in 504.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011NEC Style Manual. The proposed addition of the words “as applied to Hazardous (Classified)Locations)” will make it clear that the definition pertains to Articles 500 through 516 as applicable.

ResponseMessage:

Public Input No. 1756-NFPA 70-2014 [Definition: Associated Apparatus.]

Public Input No. 1821-NFPA 70-2014 [New Definition after Definition: Arc-Fault Circuit Interrup...]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey


85 of 270 4/16/2015 11:12 AM

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Kines, Haywood



86 of 270 4/16/2015 11:12 AM

First Revision No. 3920-NFPA 70-2015 [ Definition: Intrinsically Safe Apparatus. ]

Intrinsically Safe Apparatus.

Apparatus in which all the circuits are intrinsically safe.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Intrinsically Safe Apparatus appears in Articles 500, 504, and 505. The definition iscurrently in 504.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the2011 NEC Style Manual.

ResponseMessage:

Public Input No. 1757-NFPA 70-2014 [Definition: Intrinsically Safe Apparatus.]

Public Input No. 1823-NFPA 70-2014 [New Definition after Definition: Isolated (as applied to lo...]

Ballot Results


16 Eligible Voters

1 Not Returned

10 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Simmons, John L.


87 of 270 4/16/2015 11:12 AM

Wechsler, David B.


Ankele, Donald W.

Add the wording "[as applied to Hazardous (Classified) Locations]"

Wirfs, Mark C.

None.


Burns, Dave

The definitions were relocated based on direction from the TCC. Panel 14 followed this direction but is unaware ifother panels followed suit. Consistancy within the document is important to the user. If the definitions are to bemoved to Art. 100, some cross-reference should be provided for this code cycle.

Kines, Haywood


McBride, William E.

For this code cycle only, a cross-reference in 504.2 to be relocated definitions in Art 100 is recommended in thislocation for sustained usability. The code panel is moving the definition without leaving a trail where the definitionis relocated to article 100 and will result in confusion for the use of this article. 500.2 should refer users of the codeto see Article 100 for definitions formerly located in Section 500.2


88 of 270 4/16/2015 11:12 AM

First Revision No. 3921-NFPA 70-2015 [ Definitions (504.2): Intrinsical... to Simple

Appa... ]

Intrinsically Safe System [as applied to Hazardous (Classified) Locations] .

An assembly of interconnected intrinsically safe apparatus, associated apparatus, and interconnectingcables, in that those parts of the system that may be used in hazardous (classified) locations areintrinsically safe circuits.

Informational Note: An intrinsically safe system may include more than one intrinsically safe circuit.

Simple Apparatus [as applied to Hazardous (Classified) Locations] .

An electrical component or combination of components of simple construction with well-defined electricalparameters that does not generate more than 1.5 volts, 100 mA, and 25 mW, or a passive component thatdoes not dissipate more than 1.3 watts and is compatible with the intrinsic safety of the circuit in which it isused.

Informational Note: The following apparatus are examples of simple apparatus:

(1) Passive components; for example, switches, junction boxes, resistance temperature devices,and simple semiconductor devices such as LEDs

(2) Sources of stored energy consisting of single components in simple circuits with well-definedparameters; for example, capacitors or inductors, whose values are considered whendetermining the overall safety of the system

(3) Sources of generated energy; for example, thermocouples and photocells, that do notgenerate more than 1.5 volts, 100 mA, and 25 mW




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Intrinsically Safe System appears in Articles 500, 504, and 250. the term SimpleApparatus appears in Articles 500, 501, 502, 503, 504, 505, and 506. The definitions are currently in504.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011 NEC StyleManual. The proposed addition of the words “as applied to Hazardous (Classified) Locations)” willmake it clear that the definition pertains to Articles 500 through 516 as applicable.

ResponseMessage:

Public Input No. 1761-NFPA 70-2014 [Definition: Intrinsically Safe System.]

Public Input No. 1825-NFPA 70-2014 [New Definition after Definition: Special Permission.]

Public Input No. 1762-NFPA 70-2014 [Definition: Simple Apparatus.]

Ballot Results


16 Eligible Voters


89 of 270 4/16/2015 11:12 AM

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Kines, Haywood



90 of 270 4/16/2015 11:12 AM


(A) Control Drawing.

Intrinsically safe apparatus, associated apparatus, and other equipment shall be installed in accordancewith the control drawing(s).

A simple apparatus, whether or not shown on the control drawing(s), shall be permitted to be installedprovided the simple apparatus that does not interconnect intrinsically safe circuits.

Informational Note No. 1: The control drawing identification is marked on the apparatus.

Informational Note No. 2: Associated apparatus with a marked Um of less than 250 V may requireadditional overvoltage protection at the inputs to limit any possible fault voltages to less than theUm marked on the product.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The Exception was removed and positive language inserted.

Response Message:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


91 of 270 4/16/2015 11:12 AM

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


92 of 270 4/16/2015 11:12 AM

First Revision No. 3990-NFPA 70-2015 [ Sections 504.10(B), 504.10(C), 504.10(D) ]

(B) Location.

Intrinsically safe apparatus shall be permitted to be installed in any hazardous (classified) location forwhich it has been identified.

Associated apparatus shall be permitted to be installed in any hazardous (classified) location for which ithas been identified.

Simple apparatus shall be permitted to be installed in any hazardous (classified) location in which themaximum surface temperature of the simple apparatus does not exceed the ignition temperature of theflammable gases or vapors, flammable liquids, combustible dusts, or ignitible fibers/flyingspresent accordance with 504.10(D) .

(C) Enclosures.

General-purpose enclosures shall be permitted for intrinsically safe apparatus and associated apparatusunless otherwise specified in the manufacturer’s documentation.

(D) Simple Apparatus.

For simple apparatus, the Simple apparatus shall be permitted to be installed in any hazardous(classified) location in which the maximum surface temperature of the simple apparatus does not exceedthe ignition temperature of the flammable gases or vapors, flammable liquids, combustible dusts, orignitible fibers/flyings present. The maximum surface temperature can be determined from the values ofthe output power from the associated apparatus or apparatus to which it is connected to obtain thetemperature class. The temperature class can be determined by:

(1) Reference to Table 504.10(D)

(2) Calculation using the following equation:

[504.10(D)]

where:

T = surface temperature

Po = output power marked on the associated apparatus or intrinsically safe apparatus

Rth = thermal resistance of the simple apparatus

Tamb = ambient temperature (normally 40°C) and reference Table 500.8(C)

In addition, components with a surface area smaller than 10 cm2 (excluding lead wires) may be classifiedas T5 if their surface temperature does not exceed 150°C.

Table 504.10(D) Assessment for T4 Classification According to Component Size and Temperature

Total Surface Area Excluding Lead Wires Requirement for T4 Classification

<20 mm2 Surface temperature ≤275°C

≥20 mm2 ≤10 cm2 Surface temperature ≤200°C

≥20 mm2 Power not exceeding 1.3 W*

*Based on 40°C ambient temperature. Reduce to 1.2 W with an ambient of 60°C or 1.0 W with 80°Cambient temperature.




Street Address:


93 of 270 4/16/2015 11:12 AM

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The reorganization of the sections improve the usability of the Code. No technicalrequirements have been changed.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


94 of 270 4/16/2015 11:12 AM


504.60 Bonding.

(A) Hazardous Locations Intrinsically Safe Apparatus .

In hazardous (classified) locations, intrinsically Intrinsically safe apparatus, if of metal, shall be bonded inthe hazardous (classified) location in accordance with 250.100 501.30(A) , 502.30(A) , 503.30(A) ,505.25 , or 506.25 , as applicable. .

(B) Unclassified Metal Raceways .

In unclassified locations, where Where metal raceways are used for intrinsically safe system wiring, inhazardous (classified) locations, associated apparatus shall be bonded bonding at all ends of theraceway, regardless of the location, shall be in accordance with 501.30(A), 502.30(A), 503.30(A),505.25, or 506.25, as applicable.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The new language provides for improved clarity and usability. Regardless of where installed, theintrinsically safe apparatus, the associated apparatus, and metal raceways shall be bonded inaccordance with the hazardous location rules.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.


95 of 270 4/16/2015 11:12 AM

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


96 of 270 4/16/2015 11:12 AM

First Revision No. 3905-NFPA 70-2015 [ Definition: Combustible Gas Detection System.

]

Combustible Gas Detection System.

A protection technique utilizing stationary gas detectors in industrial establishments.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Combustible Gas Detection System is used in Articles 500 and 505. The definition hasbeen relocated to Article 100 to comply with Section 2.2.2.1 of the 2011 NEC Style Manual.

ResponseMessage:

Public Input No. 1763-NFPA 70-2014 [Definition: Combustible Gas Detection System.]

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan


97 of 270 4/16/2015 11:12 AM

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Retain the defined terms with a reference to see Article 100 for the actual definition. This will help the user inapplying Articles 500 through 504 and 510 through 516.

Wirfs, Mark C.

None.


Kines, Haywood



98 of 270 4/16/2015 11:12 AM

First Revision No. 3922-NFPA 70-2015 [ Definition: Electrical and Electronic Equipment.

]

Electrical and Electronic Equipment.

Materials, fittings, devices, appliances, and the like that are part of, or in connection with, an electricalinstallation.

Informational Note: Portable or transportable equipment having self-contained power supplies,such as battery-operated equipment, could potentially become an ignition source in hazardous(classified) locations. See ANSI/ISA-12.12.03-2011, Standard for Portable Electronic ProductsSuitable for Use in Class I and II, Division 2, Class I Zone 2 and Class III, Division 1 and 2Hazardous (Classified) Locations .




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term is generic and does not require a definition. The informational note has beenrelocated to 500.4(B) and 505.4(B).

ResponseMessage:

Public Input No. 1826-NFPA 70-2014 [New Definition after Definition: Electronically Actuated Fu...]

Public Input No. 1765-NFPA 70-2014 [Definition: Electrical and Electronic Equipment.]

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.


99 of 270 4/16/2015 11:12 AM

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


100 of 270 4/16/2015 11:12 AM

First Revision No. 3917-NFPA 70-2015 [ Definition: Unclassified Locations. ]

Unclassified Locations.

Locations determined to be neither Class I, Division 1; Class I, Division 2; Class I, Zone 0; Class I, Zone1; Class I, Zone 2; Class II, Division 1; Class II, Division 2; Class III, Division 1; Class III, Division 2;Zone 20; Zone 21; Zone 22; or any combination thereof.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Unclassified Locations is used in Articles 500, 501, 502, 503, 504, 505, 506, 511, 513,514, 516, and 400. The definition of this term has been relocated to Article 100 to comply withSection 2.2.2.1 of the 2011 NEC Style Manual.

ResponseMessage:

Public Input No. 1776-NFPA 70-2014 [Definition: Unclassified Locations.]

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.


101 of 270 4/16/2015 11:12 AM

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.


Wirfs, Mark C.

None.


Kines, Haywood



102 of 270 4/16/2015 11:12 AM

First Revision No. 3927-NFPA 70-2015 [ Definitions (505.2): Encapsulati... to Type of

Pro... ]

Encapsulation “m.” “m”.

Type of protection where electrical parts that could ignite an explosive atmosphere by either sparking orheating are enclosed in a compound in such a way that this explosive atmosphere cannot be ignited.

Informational Note No. 1: See ANSI/ISA-60079-18 (12.23.01)-2009, Explosive atmospheres — Part18: Equipment protection by encapsulation “m”; and ANSI/UL 60079-18-2009, Explosiveatmospheres — Part 18: Equipment protection by encapsulation “m.”

Informational Note No. 2: Encapsulation is designated type of protection “ma” for use in Zone 0locations. Encapsulation is designated type of protection “m” or “mb” for use in Zone 1 locations.Encapsulation is designated type of protection “mc” for use in Zone 2 locations.

Flameproof “d.” “d”.

Type of protection where the enclosure will withstand an internal explosion of a flammable mixture thathas penetrated into the interior, without suffering damage and without causing ignition, through any jointsor structural openings in the enclosure, of an external explosive gas atmosphere consisting of one or moreof the gases or vapors for which it is designed.

Informational Note: See ANSI/ISA-60079-1 (12.22.01)-2009, Explosive Atmospheres, Part 1:Equipment protection by flameproof enclosures “d”; and ANSI/UL 60079-1-2009, ElectricalApparatus for Explosive Gas Atmospheres — Part 1: Flameproof Enclosures “d.”

Increased Safety “e.” “e”.

Type of protection applied to electrical equipment that does not produce arcs or sparks in normal serviceand under specified abnormal conditions, in which additional measures are applied so as to giveincreased security against the possibility of excessive temperatures and of the occurrence of arcs andsparks.

Informational Note: See ANSI/ISA-60079-7 (12.16.01)-2008, Explosive Atmospheres, — Part 7:Equipment protection by increased safety “e”; and ANSI/UL 60079-7–2008, Electrical Apparatus forExplosive Gas Atmospheres — Part 7: Increased Safety “e.”

Intrinsic Safety “i.” “i”.

Type of protection where any spark or thermal effect is incapable of causing ignition of a mixture offlammable or combustible material in air under prescribed test conditions.

Informational Note No. 1: See ANSI/UL 913-2006, Intrinsically Safe Apparatus and AssociatedApparatus for Use in Class I, II, and III, Hazardous Locations; ANSI/ISA-60079-11 (12.02.01)-2011,Explosive Atmospheres: — Part 11: Equipment protection by intrinsic safety “i”; and ANSI/UL60079-11-2011, Explosive Atmospheres, — Part 11: Equipment protection by intrinsic safety “i.”

Informational Note No. 2: Intrinsic safety is designated type of protection “ia” for use in Zone 0locations. Intrinsic safety is designated type of protection “ib” for use in Zone 1 locations. Intrinsicsafety is designated type of protection “ic” for use in Zone 2 locations.

Informational Note No. 3: Intrinsically safe associated apparatus, designated by [ia], [ib], or [ic], isconnected to intrinsically safe apparatus (“ia,” “ib,” or “ic,” respectively) but is located outside thehazardous (classified) location unless also protected by another type of protection (such asflameproof).

Oil Immersion “o.” “o”.

Type of protection where electrical equipment is immersed in a protective liquid in such a way that anexplosive atmosphere that may be above the liquid or outside the enclosure cannot be ignited.

Informational Note: See ANSI/ISA-60079-6 (12.00.05)-2009, Explosive Atmospheres, — Part 6:Equipment protection by oil immersion “o”; and ANSI/UL 60079-6-2009, Electrical Apparatus forExplosive Gas Atmospheres — Part 6: Oil-Immersion “o.”


103 of 270 4/16/2015 11:12 AM

Powder Filling “q.” “q”.

Type of protection where electrical parts capable of igniting an explosive atmosphere are fixed in positionand completely surrounded by filling material (glass or quartz powder) to prevent the ignition of anexternal explosive atmosphere.

Informational Note: See ANSI/ISA-60079-5 (12.00.04)-2009, Explosive Atmospheres, — Part 5:Equipment protection by powder filling “q”; and ANSI/UL 60079-5, Electrical Apparatus forExplosive Gas Atmospheres — Part 5: Powder Filling “q.”

Pressurization “p.” “p”.

Type of protection for electrical equipment that uses the technique of guarding against the ingress of theexternal atmosphere, which may be explosive, into an enclosure by maintaining a protective gas therein ata pressure above that of the external atmosphere.

Informational Note: See ANSI/ISA UL -60079-2 (12.04.01)-2010 2015 , Explosive Atmospheres, —Part 2: Equipment protection by pressurized enclosures “p”; and IEC 60079-13-2010, Electricalapparatus for explosive gas atmospheres — Part 13: Construction and use of rooms or buildingsprotected by pressurization.

Type of Protection “n.” “n”.

Type of protection where electrical equipment, in normal operation, is not capable of igniting a surroundingexplosive gas atmosphere and a fault capable of causing ignition is not likely to occur.

Informational Note: See ANSI/UL 60079-15-2009, Electrical Apparatus for Explosive GasAtmospheres — Part 15: Type of Protection “n”; and ANSI/ISA-60079-15 (12.12.02)-2009,Explosive Atmospheres — Part 15: Equipment protection by type of protection “n.”




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The period at the end of the term header should be outside of the quotes and not inside.References were updated.

ResponseMessage:

Public Input No. 1768-NFPA 70-2014 [Definition: Encapsulation “m.”]

Public Input No. 1773-NFPA 70-2014 [Definition: Oil Immersion “o.”]

Public Input No. 1772-NFPA 70-2014 [Definition: Intrinsic Safety “i.”]

Public Input No. 1774-NFPA 70-2014 [Definition: Powder Filling “q.”]

Public Input No. 1775-NFPA 70-2014 [Definition: Type of Protection “n.”]

Public Input No. 1767-NFPA 70-2014 [Definition: Pressurization “p.”]

Public Input No. 1770-NFPA 70-2014 [Definition: Increased Safety “e.”]

Public Input No. 1769-NFPA 70-2014 [Definition: Flameproof “d.”]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All


104 of 270 4/16/2015 11:12 AM



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Update the ANSI/UL 60079-18 to 2015. Update the ANSI/UL 60079-1 to 2015.

Wirfs, Mark C.

None.


105 of 270 4/16/2015 11:12 AM


505.4 General.


106 of 270 4/16/2015 11:12 AM

(A) Documentation for Industrial Occupancies.

All areas in industrial occupancies designated as hazardous (classified) locations shall be properlydocumented. This documentation shall be available to those authorized to design, install, inspect,maintain, or operate electrical equipment at the location.

Informational Note No. 1: For examples of area classification drawings, see ANSI/API RP505-1997, Recommended Practice for Classification of Locations for Electrical Installations atPetroleum Facilities Classified as Class I, Zone 0, Zone 1, or Zone 2; ANSI/ISA-TR 60079-10-1(12.24.01)-1998 (IEC 60079-10 Mod), Recommended Practice for Classification of Locations forElectrical Installations Classified as Class I, Zone 0, Zone 1, or Zone 2 ; IEC 60079-10-1995,Electrical Apparatus for Explosive Gas Atmospheres, Classification of Hazardous Areas 2014Explosive Atmospheres — Part 10-1: Classification of Areas — Explosive gas atmospheres ; andModel Code of Safe Practice in the Petroleum Industry, Part 15: Area Classification Code forPetroleum Installations Handling Flammable Fluids , IP 15:2005 , The Energy Institute ofPetroleum , London.

Informational Note No. 2: Where gas detection equipment is used as a means of protection inaccordance with 505.8(I)(1) , (I)(2), or (I)(3), the documentation typically includes the type ofdetection equipment, its listing, installation location(s), alarm and shutdown criteria, and calibrationfrequency.


107 of 270 4/16/2015 11:12 AM


Important information relating to topics covered in Chapter 5 may be found in other publications.

Informational Note No. 1: It is important that the authority having jurisdiction be familiar withrecorded industrial experience as well as with standards of the National Fire Protection Association(NFPA), the American Petroleum Institute (API), the International Society of Automation (ISA), andthe International Electrotechnical Commission (IEC) that may be of use in the classification ofvarious locations, the determination of adequate ventilation, and the protection against staticelectricity and lightning hazards.

Informational Note No. 2: For further information on the classification of locations, see NFPA497-2012, Recommended Practice for the Classification of Flammable Liquids, Gases, or Vaporsand of Hazardous (Classified) Locations for Electrical Installations in Chemical Process Areas;ANSI/API RP 505-1997, Recommended Practice for Classification of Locations for ElectricalInstallations at Petroleum Facilities Classified as Class I, Zone 0, Zone 1, or Zone 2; ANSI/ISA-TR 60079-10-1 (12.24.01)-1998 (IEC 60079-10-Mod), Recommended Practice for Classificationof Locations for Electrical Installations Classified as Class I, Zone 0, Zone 1, or Zone 2 ; IEC60079-10-1995, Electrical Apparatus for Explosive Gas Atmospheres, Classification of HazardousAreas 2014, Explosive Atmospheres — Part 10-1: Classification of Areas — Explosive gasatmospheres ; and Model Code of Safe Practice in the Petroleum Industry, Part 15: AreaClassification Code for Petroleum Installations Handling Flammable Fluids , IP 15:2005 , TheEnergy Institute of Petroleum , London.

Informational Note No. 3: For further information on protection against static electricity andlightning hazards in hazardous (classified) locations, see NFPA 77-2014, Recommended Practiceon Static Electricity; NFPA 780-2014, Standard for the Installation of Lightning Protection Systems;and API RP 2003-1998 2008 , Protection Against Ignitions Arising Out of Static Lightning and StrayCurrents.

Informational Note No. 4: For further information on ventilation, see NFPA 30-2012 2015 ,Flammable and Combustible Liquids Code, and ANSI/API RP 505-1997, Recommended Practicefor Classification of Locations for Electrical Installations at Petroleum Facilities Classified as ClassI, Zone 0, Zone 1, or Zone 2.

Informational Note No. 5: For further information on electrical systems for hazardous (classified)locations on offshore oil and gas producing platforms, see ANSI/API RP 14FZ-2000 2013 ,Recommended Practice for Design and Installation of Electrical Systems for Fixed and FloatingOffshore Petroleum Facilities for Unclassified and Class I, Zone 0, Zone 1, and Zone 2 Locations.

Informational Note No. 6: For further information on the installation of electrical equipment inhazardous (classified) locations in general, see IEC 60079-14-1996 2013 , Electrical apparatus forexplosive gas atmospheres — Part 14: Electrical installations in explosive gas atmospheres (otherthan mines), and IEC 60079-16-1990, Electrical apparatus for explosive gas atmospheres — Part16: Artificial ventilation for the protection of analyzer(s) houses.

Informational Note No. 7: For further information on application of electrical equipment inhazardous (classified) locations in general, see ANSI/ISA-60079-0 (12.00.01)-2009 2013 ,Explosive Atmospheres — Part 0: Equipment — General Requirements; ANSI/ISA-12.01.01-1999,Definitions and Information Pertaining to Electrical Apparatus in Hazardous (Classified) Locations;and ANSI/UL 60079-0:2013 , Electrical Apparatus for Explosive Gas Atmospheres — Part 0:General Requirements.

Informational Note No. 8: Portable or transportable equipment having self-contained powersupplies, such as battery-operated equipment, could potentially become an ignition source inhazardous (classified) locations. See ANSI/ISA-12.12.03-2011, Standard for Portable ElectronicProducts Suitable for Use in Class I and II, Division 2, Class I Zone 2 and Class III, Division 1 and2 Hazardous (Classified) Locations .

Informational Note No. 9: For additional information concerning the installation of equipmentutilizing optical emissions technology (such as laser equipment) that could potentially become anignition source in hazardous (classified) locations, see ANSI/ISA-60079-28 (12.21.02)-2013,Explosive Atmospheres — Part 28: Protection of equipment and transmission systems usingoptical radiation .





108 of 270 4/16/2015 11:12 AM

Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

This is an update of standard references. The US adoption of the IEC 60079-10-1 was publishedin August of 2014. This document replaces the ANSI/ISA-TR 12.24.01 (79-10 Mod) and the IEC60079-10 1995 documents.

Informational note no. 2 was added to (A) to clarify how gas detection is documented. The panelnotes that ANSI/API RP 505 is currently under revision and the date needs to be revised forconsistency within this document.

Informational note no. 8 was added to (B) to retain the information on battery-operated portableand transportable equipment from the definition of "Electrical and Electronic Equipment," whichhas been deleted.

informational note NO. 9 was added to clarify potential risk of ignition from electrical equipmentutilizing optical emissions technology.

ResponseMessage:



Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.


109 of 270 4/16/2015 11:12 AM


Ankele, Donald W.

Add a sentence to the end of the first paragraph under (A) "Gas detection equipment is documented inaccordance with 505.8(I)" and remove note 2.

Wirfs, Mark C.

None.


Wechsler, David B.

Regarding Informational Note 9: While potential risks of ignition from electrical equipment utilizing opticalemissions technology may exist, the design and use of suitable electrical equipment used in hazardous classifiedlocations is already addressed in the NEC. Optical emissions are not within the scope of the NEC. Therefore thereis no need to include this reference in the NEC.


110 of 270 4/16/2015 11:12 AM


(A) Classification of Locations.

Locations shall be classified depending on the properties of the flammable gases, flammable liquid–produced vapors, combustible liquid–produced vapors, combustible dusts, or fibers/flyings that may bepresent and the likelihood that a flammable or combustible concentration or quantity is present. Eachroom, section, or area shall be considered individually in determining its classification. Where pyrophoricmaterials are the only materials used or handled, these locations are outside the scope of this article.

Informational Note No. 1: See 505.7 for restrictions on area classification.

Informational Note No. 2: Through the exercise of ingenuity in the layout of electrical installationsfor hazardous (classified) locations, it is frequently possible to locate much of the equipment inreduced level of classification or in an unclassified location and, thus, to reduce the amount ofspecial equipment required.

Refrigerant machinery rooms containing ammonia refrigeration systems that are equipped with adequatemechanical ventilation that operates continuously or is initiated by a detection system that alarms at 1000ppm may be classified as “unclassified” locations.

Rooms and refrigerated areas containing ammonia refrigeration systems that are equipped with adequatemechanical ventilation that operates continuously or is initiated by a detection system that alarms at 1000ppm may be classified as “unclassified” locations.

Informational Note: For further information regarding classification and ventilation of areas involvingammonia, see ANSI/ASHRAE 15-1994 2013 , Safety Code for Mechanical Refrigeration Standardfor Refrigeration Systems ; and ANSI/CGA G2.1-1989 (14-39), Safety Requirements for theStorage and Handling of Anhydrous Ammonia .




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Standards name and date were updated. ANSI/CGA G2.1 reference was removed, as it is notapplicable to ammonia systems. The revision clarifies that areas containing ammonia refrigerationmay be classified as “unclassified” locations based on the use of gas detection and adequateventilation, in order to harmonize with the ASHRAE standard.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All


111 of 270 4/16/2015 11:12 AM



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

The Task Group developed the change of the (A) title to GENERAL based on applicability and context coveragefor 500.5(A). They FAILED to do the SAME for 505.5 (A) and 506.5(A). The same logic and style manual basisapplies and this should have been ALSO changed. We need to modify the 505.5(A) title to GENERAL.


112 of 270 4/16/2015 11:12 AM


(A) Group IIC.

Atmospheres containing acetylene, hydrogen, or flammable gas, flammable liquid–produced vapor, orcombustible liquid–produced vapor mixed with air that may burn or explode, having either a maximumexperimental safe gap (MESG) value less than or equal to 0.50 mm or minimum igniting current ratio(MIC ratio) (MIC) ratio less than or equal to 0.45. [497:3.3.5.2.1 3.3.5.2.3 ]

Informational Note: Group IIC is equivalent to a combination of Class I, Group A, and Class I,Group B, as described in 500.6(A)(1) and (A)(2).




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The extract was updated.

Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy


113 of 270 4/16/2015 11:12 AM

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.




Wirfs, Mark C.

None


114 of 270 4/16/2015 11:12 AM

First Revision No. 3949-NFPA 70-2015 [ Section No. 505.6(C) ]

(C) Group IIA.

Atmospheres containing acetone, ammonia, ethyl alcohol, gasoline, methane, propane, or flammable gas,flammable liquid–produced vapor, or combustible liquid–produced vapor mixed with air that may burn orexplode, having either a maximum experimental safe gap (MESG) value greater than 0.90 mm orminimum igniting current ratio (MIC ratio) (MIC) ratio greater than 0.80. [497:3.3.5.2.3 3.3.5.2.1 ]

Informational Note: Group IIA is equivalent to Class I, Group D as described in 500.6(A)(4).




Street Address:

City:

State:

Zip:


Committee Statement


Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan


115 of 270 4/16/2015 11:12 AM

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.




Wirfs, Mark C.

None.


116 of 270 4/16/2015 11:12 AM


(F) Available Short-Circuit Current for Type of Protection “e”.

The Unless listed and marked for connection to circuits with higher available short-circuit current, theavailable short-circuit current for electrical equipment using type of protection “e” for the field wiringconnections in Zone 1 locations shall be limited to 10,000 rms symmetrical amperes to reduce thelikelihood of ignition of a flammable atmosphere by an arc during a short-circuit event.

Informational Note: Limitation of the available short-circuit current to this level may require theapplication of current-limiting fuses or current-limiting circuit breakers.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Where listed and marked, equipment evaluated for a higher available short circuit currentcould be applied in a hazardous (classified) location.

ResponseMessage:

Public Input No. 2398-NFPA 70-2014 [Section No. 505.7(F)]

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


117 of 270 4/16/2015 11:12 AM


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


118 of 270 4/16/2015 11:12 AM


(B) Purged and Pressurized Pressurization “p” .

This protection technique shall be permitted for equipment in those Class I, Zone 1 or Zone 2 locations forwhich it is identified.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: This revision corrects the use of the term and aligns with the others in 505.8.

Response Message:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan


119 of 270 4/16/2015 11:12 AM

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


120 of 270 4/16/2015 11:12 AM


(C) Intrinsic Safety “i” .

This protection technique shall be permitted for apparatus and associated apparatus in Class I, Zone 0,Zone 1, or Zone 2 locations for which it is listed.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The type of protection letter has been added to align with the rest of 505.8.

Response Message:

Public Input No. 3072-NFPA 70-2014 [Section No. 505.8(C)]

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan


121 of 270 4/16/2015 11:12 AM

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


122 of 270 4/16/2015 11:12 AM



123 of 270 4/16/2015 11:12 AM

(2) Zone Equipment.


124 of 270 4/16/2015 11:12 AM

Equipment meeting one or more of the protection techniques described in 505.8 shall be marked with allof the following in the order shown:

(1) Class

(2) Zone

(3) Symbol “AEx”

(4) Protection technique(s) in accordance with Table 505.9(C)(2)(4)

(5) Applicable material group in accordance with Table 505.9(C)(1)(2) or a specific gas or vapor

(6) Temperature classification in accordance with 505.9(D)(1)

Exception No. 1: Associated apparatus NOT suitable for installation in a hazardous (classified)location shall be required to be marked only with (3), (4), and (5), but BOTH the symbol AEx (3)and the symbol for the type of protection (4) shall be enclosed within the same square brackets, forexample, [AEx ia] IIC.

Exception No. 2: Simple apparatus as defined in 504.2 shall not be required to have a markedoperating temperature or temperature class.

Exception No. 3: Fittings for the termination of cables shall not be required to have a markedoperating temperature or temperature class.

Informational Note No. 1: An example of the required marking for intrinsically safe apparatus forinstallation in Class I, Zone 0 is “Class I, Zone 0, AEx ia IIC T6.” An explanation of the marking thatis required is shown in Informational Note Informational Note Figure 505.9(C)(2), No.1,, .

Informational Note No. 2: An example of the required marking for intrinsically safe associatedapparatus mounted in a flameproof enclosure for installation in Class I, Zone 1 is “Class I, Zone 1AEx d[ia] IIC T4.”

Informational Note No. 3: An example of the required marking for intrinsically safe associatedapparatus NOT for installation in a hazardous (classified) location is “[AEx ia] IIC.”

Informational Note No. 4: The EPL (or equipment protection level) may appear in the productmarking. EPLs are designated as G for gas, D for dust, or M for mining and are then followed by aletter (a, b, or c) to give the user a better understanding as to whether the equipment provideseither (a) a “very high,” (b) a “high,” or (c) an “enhanced” level of protection against ignition of anexplosive atmosphere. For example, an a Class I, Zone 1, AEx d IIC T4 motor (which is suitable byprotection concept for application in Zone 1) may additionally be marked with an EPL of “Gb” toindicate that it was provided with a high level of protection, such as Class I, Zone 1 AEx d IIC T4Gb.

Informational Note No. 5: Equipment installed outside a Zone 0 location, electrically connected toequipment located inside a Zone 0 location, may be marked Class I, Zone 0/1. The “/” indicates thatequipment contains a separation element and can be installed at the boundary between a Zone 0and a Zone 1 location. See ANSI/ISA-60079-26, Electrical Apparatus for Use in Class I, Zone 0Hazardous (Classified) Locations.

Informational Note Figure 505.9(C)(2), No.1, Zone Equipment Marking.

Table 505.9(C)(2)(4) Types of Protection Designation

Designation Technique Zone*

d Flameproof enclosure 1

db Flameproof enclosure 1

e Increased safety 1

eb Increased safety 1

ia Intrinsic safety 0


125 of 270 4/16/2015 11:12 AM


ib Intrinsic safety 1

ic Intrinsic safety 2

[ia] Associated apparatus Unclassified**

[ib] Associated apparatus Unclassified**

[ic] Associated apparatus Unclassified**

ma Encapsulation 0

m Encapsulation 1

mb Encapsulation 1

mc Encapsulation 2

nA Nonsparking equipment 2

nAc Nonsparking equipment 2

nCSparking equipment in which the contacts are suitably protected other thanby restricted breathing enclosure

2

nCcSparking equipment in which the contacts are suitably protected other thanby restricted breathing enclosure

2

nR Restricted breathing enclosure 2

nRc Restricted breathing enclosure 2

o Oil immersion 1

ob Oil immersion 1

px Pressurization 1

pxb Pressurization 1

py Pressurization 1

pyb Pressurization 1

pz Pressurization 2

pzc Pressurization 2

q Powder filled 1

qb Powder filled 1

*Does not address use where a combination of techniques is used.

**Associated apparatus is permitted to be installed in a hazardous (classified) location if suitably protectedusing another type of protection.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: Class I, Zone 1 is missing from the example marking string.

Response Message:



126 of 270 4/16/2015 11:12 AM

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


127 of 270 4/16/2015 11:12 AM


(1) Equipment Provided with Threaded Entries for NPT Threaded Conduit or Fittings.

For equipment provided with threaded entries for NPT threaded conduit or fittings, listed conduit, listedconduit fittings, or listed cable fittings shall be used.

All NPT threaded conduit and fittings referred to herein shall be threaded with a National (American)Standard Pipe Taper (NPT) thread.

NPT threaded entries into explosionproof or flameproof equipment shall be made up with at least fivethreads fully engaged.

Exception: For listed explosionproof or flameproof equipment, factory threaded factory-threaded NPTentries shall be made up with at least 41⁄2 threads fully engaged.

Informational Note No. 1: Thread specifications for male NPT threads are located in ANSI/ASMEB1.20.1-1983 2013 , Pipe Threads, General Purpose (Inch).

Informational Note No. 2: Female NPT threaded entries use a modified National Standard PipeTaper (NPT) thread with thread form per ANSI/ASME B1.20.1-1983 2013 , Pipe Threads, GeneralPurpose (Inch). See ANSI UL/ISA 60079-1 /UL 60079-1:2013, Explosive Atmospheres — Part 1:Equipment Protection by Flameproof Enclosures “d” ; and ANSI/ISA 60079-1:2013 , ElectricalApparatus for Explosive Gas Atmospheres — Part 1: Equipment Protection by FlameproofEnclosures “d.” “d”.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Section 3.3.4 of the 2011 NEC Style Manual states that words and terms shall avoid colloquiallanguage. Specifically, the word “herein” is cited as a word that can be removed without affectingclarity. With the removal of this text, clarity is unaffected.

References were updated.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All




128 of 270 4/16/2015 11:12 AM

0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

update the reference to ANSI/UL 60079-1 to 2015

Wirfs, Mark C.

None.


129 of 270 4/16/2015 11:12 AM


(2) Equipment Provided with Threaded Entries for Metric Threaded Conduit or Fittings.

For equipment with metric threaded entries, listed conduit fittings or listed cable fittings shall be used.Such entries shall be identified as being metric, or listed adapters to permit connection to conduit or NPTthreaded fittings shall be provided with the equipment and shall be used for connection to conduit or NPTthreaded fittings.

Metric threaded entries fittings installed into explosionproof or flameproof equipment entries shall have aclass of fit of at least 6g/6H and be made up with at least five threads fully engaged for Groups C, D, IIB,or IIA and not less than eight threads fully engaged for Groups A, B, IIC, or IIB + H 2 and wrenchtight .

Informational Note: Threading specifications for metric threaded entries are located in ISO965/1-1980 965-1-2013 , ISO general pupose purpose metric screw threads — Tolerances — Part1: Principles and basic data; and ISO 965-3-1998, ISO general purpose metric screw threads —Tolerances — Part 3: Deviations for constructional screw threads; and ISO 965/3-1980, MetricScrew Threads .




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Section 505.9(E)(2) is not consistent with the equipment standards used to assess flame-proofequipment. The current standard for flameproof equipment (ANSI/ISA-60079-1) requires at least 5full metric threads, regardless of gas group. Testing and field experience has demonstrated that 5thread engagement is sufficient for all groups. References were updated.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey


130 of 270 4/16/2015 11:12 AM

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Regarding paragraph 2, the paragraph needs to be further edited to remove the phrase "have a class of fit of atleast 6g/6H and". This is because the fittings are required in the first paragraph to be listed. The class of fit is arequirement of listing. Therefore it is not needed to require gauging of the threads in the field.


The product standards for fittings and equipment already include the necessary class of fit. "shall have a class offit of at least 6g/6H and" is not required and can be deleted.

Wirfs, Mark C.

None.


131 of 270 4/16/2015 11:12 AM



Where an An optical fiber cable, contains conductors that are capable of with or without current- carryingcurrent (composite optical fiber cable), the optical fiber cable shall be installed to address the associatedfire hazard and sealed to address the associated explosion hazard in accordance with the requirementsof Articles 505.15 and 505.16.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:


ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans


132 of 270 4/16/2015 11:12 AM

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


133 of 270 4/16/2015 11:12 AM


(A) Class I, Zone 0.

In Class I, Zone 0 locations, only intrinsically safe equipment protected by intrinsic safety “ia” andequipment protected by encapsulation “ma” shall be connected using intrinsically safe “ia” circuits withwiring methods in accordance with Article 504 shall be permitted .




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The current text permits any wiring method as referenced to Article 504.20 wiring methods, whichthus permits any unclassified wiring method, which would permit the connection of “ma” equipmentto any wiring method, as well as any equipment suitable for Zone 1 and Zone 2 to use any wiringmethod, as referenced by 501.15(B)(1)(a) and 501.15(C)(1)(a). The new text correctly limits wiringmethods for Zone 0 to intrinsically safe circuits only.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.

Kines, Haywood


Massey, L. Evans


134 of 270 4/16/2015 11:12 AM

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Burns, Dave

The additional text appears to add confusion and seems to add requirements that are beyond the use of ‘ia’circuits for Class I, Zone 0 applications.

McBride, William E.

The additional text adds confusion and seems to add requirements that are beyond the use of ‘ia’ circuits forClass I, Zone 0 applications.


135 of 270 4/16/2015 11:12 AM


(1) General.

In Class I, Zone 1 locations, the wiring methods in 505.15(B)(1) (a) through (B)(1)(i) shall be permitted.

(a) All wiring methods permitted by 505.15(A) .

(b) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, and where the cable is notsubject to physical damage, Type MC-HL cable listed for use in Class I, Zone 1 or Division 1locations, with a gas/vaportight continuous corrugated metallic sheath, an overall jacket of suitablepolymeric material, and a separate equipment grounding conductor(s) in accordance with 250.122,and terminated with fittings listed for the application. Type MC-HL cable shall be installed inaccordance with the provisions of Article 330, Part II.

(c) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, and where the cable is notsubject to physical damage, Type ITC-HL cable listed for use in Class I, Zone 1 or Division 1locations, with a gas/vaportight continuous corrugated metallic sheath and an overall jacket ofsuitable polymeric material, and terminated with fittings listed for the application. Type ITC-HL cableshall be installed in accordance with the provisions of Article 727.

Informational Note: See 727.4 and 727.5 for restrictions on use of Type ITC cable.

(d) Type MI cable terminated with fittings listed for Class I, Zone 1 or Division 1 locations. Type MI cableshall be installed and supported in a manner to avoid tensile stress at the termination fittings.

(e) Threaded rigid metal conduit, or threaded steel intermediate metal conduit.

(f) Type PVC conduit and Type RTRC conduit shall be permitted where encased in a concrete envelopea minimum of 50 mm (2 in.) thick and provided with not less than 600 mm (24 in.) of cover measuredfrom the top of the conduit to grade. Threaded rigid metal conduit or threaded steel intermediatemetal conduit shall be used for the last 600 mm (24 in.) of the underground run to emergence or tothe point of connection to the aboveground raceway. An equipment grounding conductor shall beincluded to provide for electrical continuity of the raceway system and for grounding of non–current-carrying metal parts.

(g) Intrinsic safety type of protection “ib” shall be permitted using the wiring methods specified in Article504.

Informational Note: For entry into enclosures required to be flameproof, explosionproof, or ofincreased safety, see the information on construction, testing, and marking of cables;flameproof and increased safety cable fittings; and flameproof and increased safety cordconnectors in ANSI/UL 2225-2011, Cables and Cable-Fittings for Use in Hazardous(Classified) Locations.

(h) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall bepermitted to be installed in raceways in accordance with 505.15(B). Optical fiber cable shall besealed in accordance with 505.16.

Informational Note: For entry into enclosures required to be flameproof, explosionproof, or ofincreased safety, see the information on construction, testing, and marking of cables;flameproof and increased safety cable fittings; and flameproof and increased safety cordconnectors in ANSI/UL 2225-2011, Cables and Cable-Fittings for Use in Hazardous(Classified) Locations.

(i) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, for applications limited to 600volts nominal or less, for cable diameters 25 mm (1 in.) or less, and where the cable is not subject tophysical damage, Type TC-ER-HL cable listed for use in Class I, Zone 1 locations, with an overalljacket and a separate equipment grounding conductor(s) in accordance with 250.122, andterminated with fittings listed for the location, Type TC-ER-HL cable shall be installed in accordancewith the provisions of Article 336, including the restrictions of 336.10(7) .


136 of 270 4/16/2015 11:12 AM




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The diameter of the cable should not be restricted to 25 mm in item (i).

Response Message:




Ballot Results


16 Eligible Voters

1 Not Returned

11 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Blais, Steven J.

Type TC-ER-HL is limited to 1” by the product standard, and should continue to be limited in size and use to


137 of 270 4/16/2015 11:12 AM

maintain the safety of wiring methods in Class I, Zone 1 locations.

Burns, Dave

As currently written, there are no restrictions in the use of non-armored cable in Zone 1 locations which couldcompromise the level of safety at the location. The use of this cable in Zone 1 locations is suitable provided thereare appropriate restrictions as identified in the proposed text below. The new text in (i) should be modified asfollows: (i) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, for applications limited to 600 volts,nominal, or less and where protected from damage by location or a suitable guard, listed Type TC-ER-HL cablewith an overall jacket and a separate equipment grounding conductor(s) in accordance with 250.122 and installedin accordance with the provisions of Article 336.10 including the restrictions of 336.10 (7) shall be permitted for thefollowing applications: (1) For applications limited to 150 volts, nominal, or less and limited to 30A circuitmaximum. (2) For applications above the limitations identified in (1), a metallic shield encompassing all the currentcarrying conductors of sufficient material and size that will provide a reliable ground fault path that will ensure theoperation of a ground fault protection device shall be required.

McBride, William E.

The unrestricted use of unarmored cable in Class I, Zone 1 locations is not justified as electrical protection maybe compromised. The new text in (i) should be modified as follows: (i) In industrial establishments with restrictedpublic access, where the conditions of maintenance and supervision ensure that only qualified persons service theinstallation, for applications limited to 600 volts, nominal, or less and where protected from damage by location ora suitable guard, listed Type TC-ER-HL cable with an overall jacket and a separate equipment groundingconductor(s) in accordance with 250.122 and installed in accordance with the provisions of Article 336.10including the restrictions of 336.10 (7) shall be permitted for the following applications: (1) For applications limitedto 150 volts, nominal, or less and limited to 30A circuit maximum. (2) For applications above the limitationsidentified in (1), a metallic shield encompassing all the current carrying conductors of sufficient material and sizethat will provide a reliable ground fault path that will ensure the operation of a ground fault protection device shallbe required.


138 of 270 4/16/2015 11:12 AM


(1) General.

In Class I, Zone 2 locations, the following wiring methods shall be permitted. :

(1) All wiring methods permitted by 505.15(B) .

(2) Types MC, MV, TC, or TC-ER cable, including installation in cable tray systems. The cable shall beterminated with listed fittings. Single conductor Type MV cables shall be shielded or metallic-armored.



(5) Enclosed gasketed busways, enclosed gasketed wireways.

(6) In industrial establishments with restricted public access, where the conditions of maintenance andsupervision ensure that only qualified persons service the installation, and where metallic conduitdoes not provide sufficient corrosion resistance, listed reinforced thermosetting resin conduit (RTRC),factory elbows, and associated fittings, all marked with the suffix -XW, and Schedule 80 PVC conduit,factory elbows, and associated fittings shall be permitted. Where seals are required for boundaryconditions as defined in 505.16(C)(1)(b), the Zone 1 wiring method shall extend into the Zone 2 areato the seal, which shall be located on the Zone 2 side of the Zone 1/Zone 2 boundary.

(7) Intrinsic safety type of protection “ic” shall be permitted using any of the wiring methods permitted forunclassified locations. Intrinsic safety type of protection “ic” systems shall be installed in accordancewith the control drawing(s). Simple apparatus, not shown on the control drawing, shall be permittedin an intrinsic safety type of protection “ic” circuit, provided that the simple apparatus does notinterconnect the intrinsic safety type of protection “ic” systems to any other circuit.

Informational Note: Simple apparatus is defined in 504.2.

(8) Optical fiber cable of Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall bepermitted to be installed in cable trays or any other raceway in accordance with 505.15(C). Opticalfiber cable shall be sealed in accordance with 505.16.

(9) Cablebus.

Separate intrinsic safety type of protection “ic” systems shall be installed in accordance with one of thefollowing:

(1) In separate cables

(2) In multiconductor cables where the conductors of each circuit are within a grounded metal shield

(3) In multiconductor cables where the conductors of each circuit have insulation with a minimumthickness of 0.25 mm (0.01 in.)




Street Address:

City:

State:

Zip:


Committee Statement


139 of 270 4/16/2015 11:12 AM

CommitteeStatement:


ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


140 of 270 4/16/2015 11:12 AM


505.17 Flexible Cables, Cords and Connections.


141 of 270 4/16/2015 11:12 AM

(A) Flexible Cords, Class I, Zones 1 and 2.

A flexible cord shall be permitted for connection between portable lighting equipment or other portableutilization equipment and the fixed portion of their supply circuit. Flexible cord shall also be permitted forthat portion of the circuit where the fixed wiring methods of 505.15(B) and (C) cannot provide thenecessary degree of movement for fixed and mobile electrical utilization equipment in an industrialestablishment where conditions of maintenance and engineering supervision ensure that only qualifiedpersons install and service the installation, and where the flexible cord is protected by location or by asuitable guard from damage. The length of the flexible cord shall be continuous. Where flexible cords areused, the cords shall comply with the following:

(1) Be of a type listed for extra-hard usage.

(2) Contain, in addition to the conductors of the circuit, an equipment grounding conductor complyingwith 400.23.

(3) Be connected to terminals or to supply conductors in an approved manner.

(4) Be supported by clamps or by other suitable means in such a manner that there will be no tensionon the terminal connections.

(5) Be terminated with a listed cord connector that maintains the type of protection where the flexiblecord enters boxes, fittings, or enclosures that are required to be explosionproof or flameproof.

(6) Cord entering an increased safety “e” enclosure shall be terminated with a listed increased safety “e”cord connector.

Informational Note: See 400.10400.10 400.10 400.7 for permitted uses of flexible cords.

Electric submersible pumps with means for removal without entering the wet-pit shall be consideredportable utilization equipment. The extension of the flexible cord within a suitable raceway between thewet-pit and the power source shall be permitted.

Electric mixers intended for travel into and out of open-type mixing tanks or vats shall be consideredportable utilization equipment.

Informational Note: See 505.18 for flexible cords exposed to liquids having a deleterious effect onthe conductor insulation.


142 of 270 4/16/2015 11:12 AM

(B) Power, Control, and Instrumentation Connections for Zone 1.

To facilitate replacement in industrial establishments with restricted public access, where the conditionsof maintenance and supervision ensure that only qualified persons service the installation, and wherethe cable is not subject to physical damage; power, control, and instrumentation shall be permitted to beconnected through Type TC-ER-HL cable, by means of attachment plugs and receptacles, provided thatall of the following conditions apply:

(1) Attachment plug and receptacle are listed for use in Class I, Zone 1 locations and for use withTC-ER-HL cable.

Exception: A Class I, Zone 1 listing is not required if the circuit type of protection is “ia” or “ib”.

(2) Unless the attachment plug and receptacle are interlocked mechanically or electrically, orotherwise designed so that they cannot be separated when the contacts are energized and thecontacts cannot be energized when the plug and socket outlet are separated, a switch listed forthe location is provided so that the attachment plug or receptacle is not depended on to interruptcurrent.

Exception: A switch is not required if the circuit type of protection is “ia” or “ib”.

(3) Type TC-ER-HL cable is listed for use in Class I, Zone 1 locations.

(4) Type TC-ER-HL cable is installed in accordance with the provisions of Article 336 , including therestrictions of 336.10(7) .


(6) Unless the attachment plug and receptacle are interlocked mechanically or electrically, orotherwise designed so that they cannot be separated when the contacts are energized and thecontacts cannot be energized when the plug and socket outlet are separated, the instrumentationreceptacle carries a label warning against plugging or unplugging under load.

(C) Power, Control, and Instrumentation Connections for Zone 2.

To facilitate replacements, process power, control instruments and instrumentation shall be permitted tobe connected through flexible cords, listed Type TC-ER cable or Type TC-ER-HL cable, by means ofattachment plugs, and receptacles, provided that all of the following conditions apply:

(1) Attachment plug and receptacle are listed for use in Class I, Zone 2 locations and for use withflexible cords, Type TC-ER cable or Type TC-ER-HL cable, as applicable, and shall be of thelocking and grounding type.

Exception: A Class I, Zone 2 listing is not required if the circuit type of protection is “ia”, “ib”, or“ic”.

(2) Unless the attachment plug and receptacle are interlocked mechanically or electrically, or otherwisedesigned so that they cannot be separated when the contacts are energized and the contactscannot be energized when the plug and socket outlet are separated, a switch listed for the locationis provided so that the attachment plug or receptacle is not depended on to interrupt current.

Exception: A switch is not required if the circuit type of protection is “ia”, “ib”, or “ic”.

(2) The current does not exceed 3 amperes at 120 volts, nominal.

(3) The power-supply flexible cord does not exceed 900 mm (3 ft), is of a type listed for extra-hardusage or for hard usage if protected by location, and is supplied through an attachment plug andreceptacle of the locking and grounding type. if applicable.

(4) Type TC-ER cable or Type TC-ER-HL cable is installed in accordance with the provisions of Article336 , including the restrictions of 336.10(7) , if applicable


(6) The Unless the attachment plug and receptacle are interlocked mechanically or electrically, orotherwise designed so that they cannot be separated when the contacts are energized and thecontacts cannot be energized when the plug and socket outlet are separated, the instrumentationreceptacle carries a label warning against unplugging under load.


143 of 270 4/16/2015 11:12 AM




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Types TC-ER and TC-ER-HL are added as permissible wiring methods for the connection ofpower, control, and instrumentation in a Class I, Zone 1 or Zone 2 location. In addition, therequirements for flexible cords are clarified. Notation to the Article 336, including the restrictions ofSection 336.10(7), is necessary to address Type TC-ER-HL.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

9 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Wechsler, David B.


Ankele, Donald W.

Add Type TC cable to (C)(1) as it is a permitted Zone 2 wiring method.

Wirfs, Mark C.

None.



144 of 270 4/16/2015 11:12 AM

Blais, Steven J.

Type TC-ER-HL is not a flexible cord or flexible cable. Flexible cords and flexible cables are covered in Article400.

Burns, Dave

Section 505.17(B) was only for controls and instruments and the requirements for power circuits should remainseparate. The 3 Amp and 120 Volt limitation should remain for controls and instrumentation applications. Aspecific type of interlocked instrument receptacle that cannot be unplugged while energized should be required toeliminate the issues documented in the negative statements for FR 3967 and FR 3969. The requirements forcontrols and instrumentation and Power should not be comingled in the same section. The statement “onlynecessary receptacles” is vague and unenforceable and should be deleted.

McBride, William E.

Section 505.17(B) was only for controls and instruments and the requirements for power circuits should remainseparate. The 3 Amp and 120 Volt limitation should remain for controls and instrumentation applications. Aspecific type of interlocked instrument receptacle that cannot be unplugged while energized should be required toeliminate the issues documented in the negative statements for FR 3967 and FR 3969. The requirements forcontrols and instrumentation and Power should not be comingled in the same section. The statement “onlynecessary receptacles” is vague and unenforceable

Simmons, John L.

This revision permits "plug and play" installations which would indicate the purpose is to allow personnel with alower level of knowledge to connect and disconnect the instrumentation. There is no guarantee that the cable willever be supported as required in Article 336. The phrase "in industrial establishments with restricted publicaccess, where the conditions of maintenance and supervision ensure that only qualified persons service theinstallation" adds nothing to warrant an exception to the restrictions placed on these installations in the currentNEC. Why are we creating code language that is subjective and ambiguous with terms that are not defined in theNational Electrical Code? What is an “industrial establishment”? How does restricted public access make aninstallation more secure? Does the restricted access mean that fewer people will be hurt if something goeswrong? Are there some industrial locations that allow public access and others that do not? Who determines howmuch public access is allowed to comply with this relaxed requirement? Who will monitor the access? The parenttext requirements found in this section are there because hazardous gases or vapors may be present in explosivemixtures, how does restricting public access improve safety or make it less dangerous than other, non-industrial,locations? Does the phrase “where conditions of maintenance and supervision ensure that only qualified personsservice the installation” make sense? How can conditions of maintenance ensure what qualified persons do?While the NEC does provide a very loose definition of a qualified person, does the fact that a facility that isdesignated an industrial location ensure that installation and maintenance personnel are qualified to safely installelectrical equipment in hazardous locations? It is a mistake to relax any Code requirement with the belief that byloosely defining a type of facility, restricting public access and stating that some condition of maintenance willensure that qualified person will service the location. How will the fact that qualified persons are servicing theinstallation prevent a fire or explosion if there is a failure of the equipment or an accident? If a wiring application issafe for a Class I, Division 1 location in a location classified as an Industrial establishment, why isn’t theapplication safe for a non-industrial location? The whole concept of an industrial location as currently used and asproposed herein is not defined and loosely restricted. This language is confusing and unenforceable. Requiring alabel that does not reduce or eliminate the hazard in a Class 1, Zone 1 location might not prevent a worker fromplugging or unplugging equipment under load. There is always the possibility that an explosive concentration canexist and someone may unplug an instrument under load. The purpose of the National Electrical Code is to protectpersons and property from the hazard arising from the use of electricity, this language does not provide for that.505.17(B)(6) should be deleted.


145 of 270 4/16/2015 11:12 AM


505.22 Increased Safety “e” Motors and Generators.

In Class I, Zone 1 locations, Increased Safety increased safety “e” motors and generators of all voltageratings shall be listed for Zone 1 locations, and shall comply with all of the following:

(1) Motors shall be marked with the current ratio, IA/IN, and time, tE.

(2) Motors shall have controllers marked with the model or identification number, output rating(horsepower or kilowatt), full-load amperes, starting current ratio (IA/IN), and time (tE) of the motors

that they are intended to protect; the controller marking shall also include the specific overloadprotection type (and setting, if applicable) that is listed with the motor or generator.

(3) Connections shall be made with the specific terminals listed with the motor or generator.

(4) Terminal housings shall be permitted to be of substantial, nonmetallic, nonburning material, providedan internal grounding means between the motor frame and the equipment grounding connection isincorporated within the housing.

(5) The provisions of Part III of Article 430 shall apply regardless of the voltage rating of the motor.

(6) The motors shall be protected against overload by a separate overload device that is responsive tomotor current. This device shall be selected to trip or shall be rated in accordance with the listing ofthe motor and its overload protection.

(7) Sections 430.32(C) and 430.44 shall not apply to such motors.

(8) The motor overload protection shall not be shunted or cut out during the starting period.

Informational Note: Reciprocating engine-driven generators, compressors, and other equipmentinstalled in Class I, Zone 2 locations may present a risk of ignition of flammable materialsassociated with fuel, starting, compression, and so forth, due to inadvertent release or equipmentmalfunction by the engine ignition system and controls. For further information on the requirementsfor ignition systems for reciprocating engines installed in Class I, Zone 2 hazardous (classified)locations, see ANSI/ISA-12.20.01-2009 UL 122001:2014 , General Requirements for ElectricalIgnition Systems for Internal Combustion Engines in Class I, Division 2 or Zone 2, Hazardous(Classified) Locations.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: Standards title revised and renumbered.

Response Message:


Ballot Results



146 of 270 4/16/2015 11:12 AM

16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


147 of 270 4/16/2015 11:12 AM


506.1 Scope.

This article covers the requirements for the zone classification system as an alternative to the divisionclassification system covered in Article 500, Article 502, and Article 503 for electrical and electronicequipment and wiring for all voltages in Zone 20, Zone 21, and Zone 22 hazardous (classified) locationswhere fire and explosion hazards may exist due to combustible dusts or ignitible fibers/flyings.

Informational Note No. 1: For the requirements for electrical and electronic equipment and wiringfor all voltages in Class I, Division 1 or Division 2; Class II, Division 1 or Division 2; Class III,Division 1 or Division 2; and Class I, Zone 0 or Zone 1 or Zone 2 hazardous (classified) locationswhere fire or explosion hazards may exist due to flammable gases or vapors, flammable liquids, orcombustible dusts or fibers, refer to Articles 500 through 505.

Informational Note No. 2: Zone 20, Zone 21, and Zone 22 area classifications are based on themodified IEC area classification system as defined in ANSI/ISA-61241-10 (12.10.05)-2004,Electrical Apparatus for Use in Zone 20, Zone 21, and Zone 22 Hazardous (Classified) Locations— Classification of Zone 20, Zone 21, and Zone 22 Hazardous (Classified) Locations. ANSI/ISA60079– 10–2 (12.10.05)–2013, Explosive Atmospheres — Part 10–2: Classification of Areas —Combustible Dust Atmospheres .

Informational Note No. 3: The unique hazards associated with explosives, pyrotechnics, andblasting agents are not addressed in this article.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The reference to ANSI/ISA-61241-10 (12.10.05)-2004 has been updated to the currentdocument ANSI/ISA 60079-10-2 (12.10.05) – 2013.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey


148 of 270 4/16/2015 11:12 AM

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


149 of 270 4/16/2015 11:12 AM

First Revision No. 3923-NFPA 70-2015 [ Definition: Associated Nonincendive Field

Wiring Apparatus. ]

Associated Nonincendive Field Wiring Apparatus [as applied to Hazardous (Classified) Locations] .

Apparatus in which the circuits are not necessarily nonincendive themselves but that affect the energy innonincendive field wiring circuits and are relied upon to maintain nonincendive energy levels. Suchapparatus are one of the following:

(1) Electrical apparatus that has an alternative type of protection for use in the appropriate hazardous(classified) location

(2) Electrical apparatus not so protected that shall not be used in a hazardous (classified) location

Informational Note: Associated nonincendive field wiring apparatus has designated associatednonincendive field wiring apparatus connections for nonincendive field wiring apparatus and mayalso have connections for other electrical apparatus.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Associated Nonincendive Field Wiring Apparatus appears in Article 500. It is also used inthe definition of Control Diagram which has a PI to be relocated to Article 100. The definition iscurrently in 506.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011NEC Style Manual. The proposed addition of the words “(as applied to Hazardous (Classified)Locations)” will make it clear that the definition pertains to Articles 500 through 516 as applicable.

ResponseMessage:

Public Input No. 1827-NFPA 70-2014 [New Definition after Definition: Attachment Plug (Plug Cap)...]

Public Input No. 1777-NFPA 70-2014 [Definition: Associated Nonincendive Field Wiring Apparatus.]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey


150 of 270 4/16/2015 11:12 AM

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Kines, Haywood



151 of 270 4/16/2015 11:12 AM

First Revision No. 3903-NFPA 70-2015 [ Definition: Combustible Dust. ]

Moved by FR-3903

Combustible Dust.

Dust particles that are 500 microns or smaller (material passing a U.S. No. 35 Standard Sieve asdefined in ASTM E 11-09, Standard Specification for Wire Cloth and Sieves for Testing Purposes ) andpresent a fire or explosion hazard when dispersed and ignited in air.

Informational Note: See ASTM E 1226–12a, Standard Test Method for Explosibility of DustClouds , or ISO 6184-1, Explosion protection systems — Part 1: Determination of explosionindices of combustible dusts in air , for procedures for determining the explosibility of dusts.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term "Combustible Dust" is used in Articles 500, 502, 504, 505, 506, and 516. The definitionof this term has been relocated to Article 100 to comply with Section 2.2.2.1 of the 2011 NECStyle Manual.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave


152 of 270 4/16/2015 11:12 AM

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.


Wirfs, Mark C.

None.


Kines, Haywood



153 of 270 4/16/2015 11:12 AM

First Revision No. 3908-NFPA 70-2015 [ Definition: Dust-Ignitionproof. ]

Moved by FR-3908

Dust-Ignitionproof.

Equipment enclosed in a manner that excludes dusts and does not permit arcs, sparks, or heatotherwise generated or liberated inside of the enclosure to cause ignition of exterior accumulations oratmospheric suspensions of a specified dust on or in the vicinity of the enclosure.

Informational Note: For further information on dust-ignitionproof enclosures, see Type 9enclosure in ANSI/NEMA 250-2008, Enclosures for Electrical Equipment , and ANSI/UL1203-2009, Explosionproof and Dust-Ignitionproof Electrical Equipment for Hazardous(Classified) Locations .




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Dust-Ignitionproof is used in Articles 500, 502, and 506. The definition of this term hasbeen relocated to Article 100 to comply with Section 2.2.2.1 of the 2011 NEC Style Manual.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave


154 of 270 4/16/2015 11:12 AM

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.


Wirfs, Mark C.

None.


Kines, Haywood



155 of 270 4/16/2015 11:12 AM


Moved by FR-3911

Dusttight.

Enclosures constructed so that dust will not enter under specified test conditions.

Informational Note: See ANSI/ISA-12.12.01-2012, Nonincendive Electrical Equipment for Usein Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations .




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: The term is already defined in Article 100.

Response Message:

Public Input No. 1782-NFPA 70-2014 [Definition: Dusttight.]

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan


156 of 270 4/16/2015 11:12 AM

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.


Wirfs, Mark C.

None.


Kines, Haywood



157 of 270 4/16/2015 11:12 AM

First Revision No. 3924-NFPA 70-2015 [ Definition: Pressurized. ]

Pressurized [as applied to Hazardous (Classified) Locations] .

The process of supplying an enclosure with a protective gas with or without continuous flow, at sufficientpressure to prevent the entrance of combustible dust or ignitible fibers/flyings.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Pressurized appears in Articles 501, 505, 506, and 326. The definition is currently in506.2 but should be relocated to Article 100 to comply with Section 2.2.2.1 of the 2011 NEC StyleManual. The proposed addition of the words “(as applied to Hazardous (Classified) Locations)” willmake it clear that the definition pertains to Articles 500 through 516 as applicable.

ResponseMessage:

Public Input No. 1787-NFPA 70-2014 [Definition: Pressurized.]

Public Input No. 1829-NFPA 70-2014 [New Definition after Definition: Qualified Person.]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.



158 of 270 4/16/2015 11:12 AM

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


Kines, Haywood



159 of 270 4/16/2015 11:12 AM

First Revision No. 3914-NFPA 70-2015 [ Definitions (506.2): Nonincendiv... to

Nonincendiv... ]

Moved by FR-3914

Nonincendive Circuit.

A circuit, other than field wiring, in which any arc or thermal effect produced under intended operatingconditions of the equipment is not capable, under specified test conditions, of igniting the flammablegas–air, vapor–air, or dust–air mixture.

Informational Note: Conditions are described in ANSI/ISA-12.12.01-2012, NonincendiveElectrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2Hazardous (Classified) Locations .

Nonincendive Equipment.

Equipment having electrical/electronic circuitry that is incapable, under normal operating conditions, ofcausing ignition of a specified flammable gas–air, vapor–air, or dust–air mixture due to arcing or thermalmeans.

Informational Note: For further information, see ANSI/ISA-12.12.01-2012, NonincendiveElectrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2Hazardous (Classified) Locations .

Nonincendive Field Wiring.

Wiring that enters or leaves an equipment enclosure and, under normal operating conditions of theequipment, is not capable, due to arcing or thermal effects, of igniting the flammable gas–air, vapor–air,or dust–air mixture. Normal operation includes opening, shorting, or grounding the field wiring.

Nonincendive Field Wiring Apparatus.

Apparatus intended to be connected to nonincendive field wiring.

Informational Note: For further information, see ANSI/ISA-12.12.01-2012, NonincendiveElectrical Equipment for Use in Class I and II, Division 2, and Class III, Divisions 1 and 2Hazardous (Classified) Locations .




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The term Nonincendive Circuit is used in Articles 500, 501, 502, and 506. The term NonincendiveEquipment is used in Articles 500, 506, and 516. The term Nonincendive Field Wiring is used inArticles 500, 501, 502, 503, 504, and 506. The term Nonincendive Field Wiring Apparatus is used inArticles 500 and 506. The definitions of these terms have been relocated to Article 100 to complywith Section 2.2.2.1 of the 2011 NEC Style Manual.

ResponseMessage:

Public Input No. 1785-NFPA 70-2014 [Definition: Nonincendive Field Wiring.]

Public Input No. 1786-NFPA 70-2014 [Definition: Nonincendive Field Wiring Apparatus.]

Public Input No. 1784-NFPA 70-2014 [Definition: Nonincendive Equipment.]

Public Input No. 1783-NFPA 70-2014 [Definition: Nonincendive Circuit.]


160 of 270 4/16/2015 11:12 AM

Ballot Results


16 Eligible Voters

1 Not Returned

12 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.


Wirfs, Mark C.

None.


Kines, Haywood



161 of 270 4/16/2015 11:12 AM

First Revision No. 3928-NFPA 70-2015 [ Definitions (506.2): Protection ... to Protection

... ]

Protection by Encapsulation “m.” “m”.

Type of protection where electrical parts that could cause ignition of a mixture of combustible dust orfibers/flyings in air are protected by enclosing them in a compound in such a way that the explosiveatmosphere cannot be ignited.

Informational Note No. 1: For additional information, see ANSI/ISA-60079-18 (12.23.01)-2009,Explosive atmospheres — Part 18: Equipment protection by encapsulation “m”; ANSI/UL60079-18-2009, Explosive atmospheres — Part 18: Equipment protection by encapsulation “m”;and ANSI/ISA-61241-18 (12.10.07)-2011, Electrical Apparatus for Use in Zone 20, Zone 21 andZone 22 Hazardous (Classified) Locations — Protection by Encapsulation “m.”

Informational Note No. 2: Encapsulation is designated level of protection “maD” or “ma” for use inZone 20 locations. Encapsulation is designated level of protection “mbD” or “mb” for use in Zone 21locations. Encapsulation is designated type of protection “mc” for use in Zone 22 locations.

Protection by Enclosure “t.” “t”.

Type of protection for explosive dust atmospheres where electrical apparatus is provided with anenclosure providing dust ingress protection and a means to limit surface temperatures.

Informational Note No. 1: For additional information, see ANSI/ISA-60079-31 (12.10.03)-2009,Explosive Atmospheres — Part 31: Equipment Dust Ignition Protection by Enclosure “t”; andANSI/ISA-61241-1 (12.10.03)-2011, Electrical Apparatus for Use in Zone 21 and Zone 22Hazardous (Classified) Locations — Protection by Enclosure “t.”

Informational Note No. 2: Protection by enclosure is designated level of protection “ta” for use inZone 20 locations. Protection by enclosure is designated level of protection “tb” or “tD” for use inZone 21 locations. Protection by enclosure is designated level of protection “tc” or “tD” for use inZone 22 locations.

Protection by Intrinsic Safety “iD.”“i”.

Type of protection where any spark or thermal effect is incapable of causing ignition of a mixture ofcombustible dust, fibers, or flyings in air under prescribed test conditions.

Informational Note No. 1: For additional information, see ANSI/ISA-60079-11 (12.01.01)-2011,Electrical Apparatus for Explosive Gas Atmospheres — Part 11: intrinsic safety “i”; ANSI/UL60079-11-2011, Electrical Apparatus for Explosive Gas Atmospheres — Part 11: Intrinsic safety “i”;and ANSI/ISA- 61241-11 (12.10.04)-2011, Electrical Apparatus for Use in Zone 20, Zone 21 andZone 22 Hazardous (Classified) Locations — Protection by Intrinsic Safety “i.”

Informational Note No. 2: Intrinsic safety is designated level of protection “iaD” or “ia” for use inZone 20 locations. Intrinsic safety is designated level of protection “ibD” or “ib” for use in Zone 21locations. Intrinsic safety is designated type of protection “ic” for use in Zone 22 locations.

Protection by Pressurization “pD.” “p”.

Type of protection that guards against the ingress of a mixture of combustible dust or fibers/flyings in airinto an enclosure containing electrical equipment by providing and maintaining a protective gasatmosphere inside the enclosure at a pressure above that of the external atmosphere.

Informational Note: For additional information, see ANSI/ISA-61241-2 (12.10.06)-2006, ElectricalApparatus for Use in Zone 21 and Zone 22 Hazardous (Classified) Locations — Protection byPressurization“pD.”




Street Address:

City:

State:

Zip:


162 of 270 4/16/2015 11:12 AM


Committee Statement

CommitteeStatement:

The periods in the term headers should be outside of the quotes and not inside. The terms "iD"and "pD" were changed to "i" and "p" to refer to the generic usage of these concepts.

ResponseMessage:

Public Input No. 1788-NFPA 70-2014 [Definition: Protection by Encapsulation “m.”]

Public Input No. 1789-NFPA 70-2014 [Definition: Protection by Enclosure “t.”]

Public Input No. 1792-NFPA 70-2014 [Definition: Protection by Intrinsic Safety “iD.”]

Public Input No. 1794-NFPA 70-2014 [Definition: Protection by Pressurization “pD.”]

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Update the reference to ANSI/UL 60079-18 to 2015 and add the reference to ANSI/UL 60079-31:2015 underprotection by enclosure "t".

Wirfs, Mark C.

None.


163 of 270 4/16/2015 11:12 AM

First Revision No. 3925-NFPA 70-2015 [ Definitions (506.2): Zone 20 Haz... to Zone 22

Haz... ]

Zone 20 Hazardous (Classified) Location.

An area where combustible dust or ignitible fibers/flyings are present continuously or for long periods oftime in quantities sufficient to be hazardous, as classified by 506.5(B)(1) .


An area where combustible dust or ignitible fibers/flyings are likely to exist occasionally under normaloperation in quantities sufficient to be hazardous, as classified by 506.5(B)(2) .


An area where combustible dust or ignitible fibers/flyings are not likely to occur under normal operationin quantities sufficient to be hazardous, as classified by 506.5(B)(3) .




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: 506.5(B) fully describes these terms. The definitions are not necessary.

Response Message:

Public Input No. 1830-NFPA 70-2014 [New Definition after Definition: Weatherproof.]

Public Input No. 1805-NFPA 70-2014 [Definition: Zone 21 Hazardous (Classified) Location.]



Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.


164 of 270 4/16/2015 11:12 AM

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

None.


165 of 270 4/16/2015 11:12 AM



Important information relating to topics covered in Chapter 5are can be found in other publications.

Informational Note No. 1: It is important that the authority having jurisdiction be familiar with therecorded industrial experience as well as with standards of the National Fire Protection Association(NFPA), the International Society of Automation (ISA), and the International ElectrotechnicalCommission (IEC) that may be of use in the classification of various locations, the determination ofadequate ventilation, and the protection against static electricity and lightning hazards.

Informational Note No. 2: For additional information concerning the installation of equipmentutilizing optical emissions technology (such as laser equipment) that could potentially become anignition source in hazardous (classified) locations, see ANSI/ISA-60079-28 (12.21.02)-2013,Explosive Atmospheres — Part 28: Protection of equipment and transmission systems usingoptical radiation .




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

An informational note has been provided to clarify potential risk of ignition from electricalequipment utilizing optical emissions technology.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.


166 of 270 4/16/2015 11:12 AM

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.


Wirfs, Mark C.

None.


Wechsler, David B.

Regarding Informational Note 2: While potential risks of ignition from electrical equipment utilizing opticalemissions technology may exist, the design and use of suitable electrical equipment used in hazardous classifiedlocations is already addressed in the NEC. Optical emissions are not within the scope of the NEC. Therefore thereis no need to include this reference in the NEC.


167 of 270 4/16/2015 11:12 AM


(1) Zone 20.

A Zone 20 location is a location in which either of the following occur:

(1) Ignitible concentrations of combustible dust or ignitible fibers/flyings are present continuously.

(2) Ignitible concentrations of combustible dust or ignitible fibers/flyings are present for long periods oftime.

Informational Note No. 1: As a guide to classification of Zone 20 locations, refer to ANSI/ISA-61241-10 (12.10.05)-2004, Electrical Apparatus for Use in Zone 20, Zone 21, and Zone 22Hazardous (Classified) Locations — Classification of Zone 20, Zone 21, and Zone 22 Hazardous(Classified) Locations. 60079-10-2 (12.10.05)-2013, Explosive Atmospheres — Part 10-2:Classification of areas — Combustible dust atmospheres .

Informational Note No. 2: Zone 20 classification includes locations inside dust containmentsystems; hoppers, silos, etc., cyclones and filters, dust transport systems, except some parts of beltand chain conveyors, etc.; blenders, mills, dryers, bagging equipment, etc.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: Standard has been revised and renumbered.

Response Message:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.


168 of 270 4/16/2015 11:12 AM

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

The Task Group developed the change of the (A) title to GENERAL based on applicability and context coveragefor 500.5(A). They FAILED to do the SAME for 505.5 (A) and 506.5(A). The same logic and style manual basisapplies and this should have been ALSO changed. We need to modify the 505.6(A) title to GENERAL.


169 of 270 4/16/2015 11:12 AM


(2) Zone 21.

A Zone 21 location is a location where one of the following apply:

(1) In which ignitible Ignitible concentrations of combustible dust or ignitible fibers/flyings are likely toexist occasionally under normal operating conditions; or

(2) In which ignitible Ignitible concentrations of combustible dust or ignitible fibers/flyings may existfrequently because of repair or maintenance operations or because of leakage; or

(3) In which equipment Equipment is operated or processes are carried on, of such a nature thatequipment breakdown or faulty operations could result in the release of ignitible concentrations ofcombustible dust or ignitible fibers/flyings and also cause simultaneous failure of electrical equipmentin a mode to cause the electrical equipment to become a source of ignition; or

(4) That is adjacent Adjacent to a Zone 20 location from which ignitible concentrations of dust or ignitiblefibers/flyings could be communicated, unless communication is prevented by adequate positivepressure ventilation from a source of clean air and effective safeguards against ventilation failure areprovided.


Informational Note No. 2: This classification usually includes locations outside dust containmentand in the immediate vicinity of access doors subject to frequent removal or opening for operationpurposes when internal combustible mixtures are present; locations outside dust containment in theproximity of filling and emptying points, feed belts, sampling points, truck dump stations, belt dumpover points, etc., where no measures are employed to prevent the formation of combustiblemixtures; locations outside dust containment where dust accumulates and where due to processoperations the dust layer is likely to be disturbed and form combustible mixtures; locations insidedust containment where explosive dust clouds are likely to occur (but neither continuously, nor forlong periods, nor frequently) as, for example, silos (if filled and/or emptied only occasionally) andthe dirty side of filters if large self-cleaning intervals are occurring.




Street Address:

City:

State:

Zip:


Committee Statement


Response Message:


Ballot Results



170 of 270 4/16/2015 11:12 AM

16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


171 of 270 4/16/2015 11:12 AM


(3) Zone 22.

A Zone 22 location is a location where one of the following apply:

(1) In which ignitible Ignitible concentrations of combustible dust or ignitible fibers/flyings are not likely tooccur in normal operation and, if they do occur, will only persist for a short period; or

(2) In which combustible Combustible dust or fibers/flyings are handled, processed, or used but in whichthe dust or fibers/flyings are normally confined within closed containers of closed systems from whichthey can escape only as a result of the abnormal operation of the equipment with which the dust orfibers/flyings are handled, processed, or used; or

(3) That is adjacent Adjacent to a Zone 21 location, from which ignitible concentrations of dust orfibers/flyings could be communicated, unless such communication is prevented by adequate positivepressure ventilation from a source of clean air and effective safeguards against ventilation failure areprovided.


Informational Note No. 2: Zone 22 locations usually include outlets from bag filter vents, because inthe event of a malfunction there can be emission of combustible mixtures; locations nearequipment that has to be opened at infrequent intervals or equipment that from experience caneasily form leaks where, due to pressure above atmospheric, dust will blow out; pneumaticequipment, flexible connections that can become damaged, etc.; storage locations for bagscontaining dusty product, since failure of bags can occur during handling, causing dust leakage;and locations where controllable dust layers are formed that are likely to be raised into explosivedust–air mixtures. Only if the layer is removed by cleaning before hazardous dust–air mixtures canbe formed is the area designated unclassified.

Informational Note No. 3: Locations that normally are classified as Zone 21 can fall into Zone 22when measures are employed to prevent the formation of explosive dust–air mixtures. Suchmeasures include exhaust ventilation. The measures should be used in the vicinity of (bag) fillingand emptying points, feed belts, sampling points, truck dump stations, belt dump over points, etc.




Street Address:

City:

State:

Zip:


Committee Statement


Response Message:


Ballot Results


172 of 270 4/16/2015 11:12 AM


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


173 of 270 4/16/2015 11:12 AM


(B) Listing.

(1) Equipment that is listed for Zone 20 shall be permitted in a Zone 21 or Zone 22 location of the samedust or ignitible fiber/flying. Equipment that is listed for Zone 21 may be used in a Zone 22 location ofthe same dust or ignitible fiber/flying.

(2) Equipment shall be permitted to be listed for a specific dust or ignitible fiber/flying or any specificcombination of dusts or ignitible fibers/flyings.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: Editorial to correct grammatical error.

Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.


174 of 270 4/16/2015 11:12 AM

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Delete 506.9(B)(2) as there are no testing, approval or area classification requirements that address one specificdust or fiber/flying.

Wirfs, Mark C.

NONE>


175 of 270 4/16/2015 11:12 AM



176 of 270 4/16/2015 11:12 AM

(2) Zone Equipment.


177 of 270 4/16/2015 11:12 AM

Equipment meeting one or more of the protection techniques described in 506.8 shall be marked with thefollowing in the order shown:

(1) Zone

(2) Symbol “AEx”

(3) Protection technique(s) in accordance with Table 506.9(C)(2)(3)

(4) Material group in accordance with 506.6 or a specific dust or ignitible fiber/flying or a specificcombination thereof

(5) Maximum surface temperature in accordance with 506.9(D), marked as a temperature value indegrees C, preceded by “T” and followed by the symbol “°C”

(6) Ambient temperature marking in accordance with 506.9(D)

Informational Note: The EPL (or equipment protection level) may can appear in the productmarking. EPLs are designated as G for gas, D for dust, or M for mining, and are then followed by aletter (a, b, or c) to give the user a better understanding as to whether the equipment provideseither (a) a “very high,” (b) a “high,” or (c) an “enhanced” level of protection against ignition of anexplosive atmosphere. For example, an a Zone 21 AEx pb IIIB T165°C motor (which is suitable byprotection concept for application in Zone 21) may can additionally be marked with an EPL of “Db”,Zone 21 AEx p IIIB T165°C Db.

Exception: Associated apparatus NOT suitable for installation in a hazardous (classified) location shallbe required to be marked only with 506.9(C)(2)(2) , and (3), and where applicable (5 4 ), but BOTH thesymbol AEx in 506.9(C)(2)(2) and the symbol for the type of protection in 506.9(C)(2)(3) shall beenclosed within the same square brackets; for example, [AEx iaD] or [AEx ia] IIIC.

Table 506.9(C)(2)(3) Types of Protection Designation


iaD Protection by intrinsic safety 20

ia Protection by intrinsic safety 20

ibD Protection by intrinsic safety 21

ib Protection by intrinsic safety 21

ic Protection by intrinsic safety 22

[iaD] Associated apparatus Unclassified**

[ia] Associated apparatus Unclassified**

[ibD] Associated apparatus Unclassified**

[ib] Associated apparatus Unclassified**

[ic] Associated apparatus Unclassified**

maD Protection by encapsulation 20

ma Protection by encapsulation 20

mbD Protection by encapsulation 21

mb Protection by encapsulation 21

mc Protection by encapsulation 22

pD Protection by pressurization 21

p Protection by pressurization 21

pb Protection by pressurization 21

tD Protection by enclosures 21

ta Protection by enclosures 20

tb Protection by enclosures 21

tc Protection by enclosures 22

*Does not address use where a combination of techniques is used.

**Associated apparatus is permitted to be installed in a hazardous (classified) location if suitably protectedusing another type of protection.


178 of 270 4/16/2015 11:12 AM

Informational Note: The “D” suffix on the type of protection designation was employed prior to theintroduction of Group IIIA, IIIB, and IIIC; which is now used to distinguish between the type ofprotection employed for Group II (Gases) or Group III (Dusts).




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Revised Item (4) to correlate the marking requirements with 506.9(B)(2).

Zone 21 was inadvertently omitted from the example marking. The text contained within theparentheses was deleted as it is now redundant.

The original text incorrectly refers to item (5) and omits item (4).

Item (5) in the list refers to the Maximum Surface Temperature which is not relevant forAssociated Apparatus that is not installed in a Hazardous (Classified) Location.

Item (4) relates to the Material Group which is only applicable in the case of [AEx ia] IIIC, asequipment listed to the earlier editions marked with 'iaD' did not require a material group to bemarked.

ResponseMessage:



Ballot Results


16 Eligible Voters

1 Not Returned

10 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Jones, Robert A.


179 of 270 4/16/2015 11:12 AM

Kines, Haywood

Massey, L. Evans

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Revise 506.9(C)(2)(4) to revert back to the original text as there are no testing, approval or area classificationrequirements that address one specific dust or fiber/flying.

Wirfs, Mark C.

NONE>


Burns, Dave

Need to remove the addition of the words "or a specific dust or ignitable fiber/flying or a specific combinationthereof". This creates confusion for the installers and inspectors. The specific dust that the device is approved forwill not likely appear on the label and will be only in the documentation. Current product standards do not permitthe listing of specific dusts.


The revision to add "or a specific dust or ignitible fiber/flying or a specific combination thereof" should not beadded. 1. The product standards supporting Article 506; ANSI/ISA 60079-0 and ANSI/UL 60079-0 do not includesuch a product marking. 2. IEC TC31 has made it quite clear that complete identification of a specific dust orfiber/flying would involve such detail that it is not practical. It is not as simple as identifying the chemical formula ofa gas or vapor. Aspects such as the chemical formula or CAS number of each constituent, along with amount ofpercentage of each, the bulk density, and the particle density could all be important. 3. The product standards fordusts or fibers/flyings are based on particle size (for exclusion) and maximum surface temperature (for layer/cloudignition). For a small portion of Intrinsic Safety, protection is based on limitation of available energy to initiate anexplosion. The maximum permitted energy of ~160?J is very conservative for dust. 4. All known equipment can beaccommodated within the requirements of the existing equipment standards. There is no need to add additionalconfusion as to what is and is not suitable. 5. At one time, there may have been a need due to the temperaturerestrictions of Table 500.8(D)(2), but that requirement was removed ~20 years ago.

McBride, William E.

Need to remove the addition of the words "or a specific dust or ignitable fiber/flying or a specific combinationthereof". This creates confusion for the installers and inspectors. The specific dust that the device is approved forwill not likely appear on the label and will be only in the documentation. Current product standards do not permitthe listing of specific dusts.


180 of 270 4/16/2015 11:12 AM


(1) Equipment Provided with Threaded Entries for NPT-Threaded Conduit or Fittings.

For equipment provided with threaded entries for NPT-threaded conduit or fittings, listed conduit fittings orlisted cable fittings shall be used. All NPT-threaded conduit and fittings referred to herein shall bethreaded with a National (American) Standard Pipe Taper (NPT) thread.

Informational Note: Thread specifications for NPT threads are located in ANSI/ASMEB1.20.1-1983 2013 , Pipe Threads, General Purpose (Inch).




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Section 3.3.4 of the 2011 NEC Style Manual states that words and terms shall avoid colloquiallanguage. Specifically, the word “herein” is cited as a word that can be removed without affectingclarity. With the removal of this text, clarity is unaffected.

The reference was updated.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave


181 of 270 4/16/2015 11:12 AM

Jones, Robert A.

Kines, Haywood

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>



(2) should not appear. 1. The product standards supporting Article 506; ANSI/ISA 60079-0 and ANSI/UL 60079-0do not include such a product marking. 2. IEC TC31 has made it quite clear that complete identification of aspecific dust or fiber/flying would involve such detail that it is not practical. It is not as simple as identifying thechemical formula of a gas or vapor. Aspects such as the chemical formula or CAS number of each constituent,along with amount of percentage of each, the bulk density, and the particle density could all be important. 3. Theproduct standards for dusts or fibers/flyings are based on particle size (for exclusion) and maximum surfacetemperature (for layer/cloud ignition). For a small portion of Intrinsic Safety, protection is based on limitation ofavailable energy to initiate an explosion. The maximum permitted energy of ~160?J is very conservative for dust.4. All known equipment can be accommodated within the requirements of the existing equipment standards.There is no need to add additional confusion as to what is and is not suitable. 5. At one time, there may have beena need due to the temperature restrictions of Table 500.8(D)(2), but that requirement was removed ~20 years ago.


182 of 270 4/16/2015 11:12 AM


(2) Equipment Provided with Threaded Entries for Metric-Threaded Conduit or Fittings.

For equipment with metric-threaded entries, listed conduit fittings or listed cable fittings shall be used.Such entries shall be identified as being metric, or listed adapters to permit connection to conduit orNPT-threaded fittings shall be provided with the equipment and shall be used for connection to conduit orNPT-threaded fittings. Metric-threaded fittings installed into equipment entries shall be made up with atleast five threads fully engaged.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Sections 342.28 and 344.28 require conduit to be threaded with NPT threads and do not permitmetric threaded conduit. Additional text added to clarify that the requirement for threadengagement is between threaded equipment entries and threaded fittings.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

13 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood



183 of 270 4/16/2015 11:12 AM

Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Ankele, Donald W.

Add the words "wrench tight" at the end of the paragraph.

Wirfs, Mark C.

NONE>


184 of 270 4/16/2015 11:12 AM



Where an An optical fiber cable contains conductors that are capable of carrying current , with or withoutcurrent-carrying conductors (composite optical fiber cable), the optical fiber cable shall be installed toaddress the associated fire hazard and sealed to address the associated explosion hazard in accordancewith the requirements of Articles 506.15 and 506.16.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:


ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans


185 of 270 4/16/2015 11:12 AM

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


186 of 270 4/16/2015 11:12 AM


(C) Zone 22.

In Zone 22 locations, the following wiring methods shall be permitted. :

(1) All wiring methods permitted in 506.15(B) .

(2) Rigid metal conduit, intermediate metal conduit, electrical metallic tubing, dusttight wireways.

(3) Type MC or MI cable with listed termination fittings.



(6) Type MC, MI, MV, TC, or TC-ER cable installed in ladder, ventilated trough, or ventilated channelcable trays in a single layer, with a space not less than the larger cable diameter between twoadjacent cables, shall be the wiring method employed. Single-conductor Type MV cables shall beshielded or metallic armored. The cable shall be terminated with listed fittings.

(7) Intrinsic safety type of protection “ic” shall be permitted using any of the wiring methods permitted forunclassified locations. Intrinsic safety type of protection “ic” systems shall be installed in accordancewith the control drawing(s). Simple apparatus, not shown on the control drawing, shall be permittedin a circuit of intrinsic safety type of protection “ic”, provided that the simple apparatus does notinterconnect the intrinsic safety type of protection “ic” circuit to any other circuit.

Informational Note: The term Simple Apparatus is defined in 504.2.

Separation of circuits of intrinsic safety type of protection “ic” shall be in accordance with one of thefollowing:

a. Be in separate cables

b. Be in multiconductor cables where the conductors of each circuit are within a grounded metalshield

c. Be in multiconductor cables where the conductors have insulation with a minimum thickness of0.25 mm (0.01 in.)

(8) Boxes and fittings shall be dusttight.

(9) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall bepermitted to be installed in cable trays or any raceway in accordance with 506.15(C). Optical fibercables shall be sealed in accordance with 506.16.

(10) Cablebus.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:



187 of 270 4/16/2015 11:12 AM

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


188 of 270 4/16/2015 11:12 AM


]

Where Class I liquids or gaseous fuels are stored, handled, or transferred, electrical wiring and electricalutilization equipment shall be designed in accordance with the requirements for Class I, Division 1 or 2hazardous (classified) locations as classified in accordance with 500.5 and 500.6, and this article. A ClassI location shall not extend beyond an unpierced wall, roof, or other solid partition that has no openings.[30A:8.3.5, 8.3.2 8.3.1, 8.3.3 ]




Street Address:

City:

State:

Zip:


Committee Statement


Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.


189 of 270 4/16/2015 11:12 AM

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


190 of 270 4/16/2015 11:12 AM


(C) Major Repair Garages, Major and Minor .


191 of 270 4/16/2015 11:12 AM

Where flammable liquids having a flash point below 38°C (100°F) such as gasoline, or gaseous fuelssuch as natural gas, hydrogen, or LPG, will not be dispensed, but repair activities that involve the transferof such fluids or gases are performed, the classification rules in (1), (2), and (3) shall apply. Wherevehicles using Class I liquids or heavier-than-air gaseous fuels (such as LPG) are repaired, hazardousarea classification guidance is found in Table 511.3(C) .

Informational Note: For additional information, see NFPA 30A -2015, Code for Motor FuelDispensing Facilities and Repair Garages , Table 8.3.2.

Table 511.3(C) Extent of Classified Locations for Major and Minor Repair Garages with Heavier-Than-AirFuel

Location

Class I

Extent of Classified Location

Division

(Group D)

Zone

(GroupIIA)

Repair garage,major (where Class Iliquids or gaseous fuelsare transferred ordispensed*)

1 1Entire space within any pit, belowgrade work area, orsubfloor work area that is not ventilated

2 2

Entire space within any pit, belowgrade work area, orsubfloor work area that is provided with ventilation of

at least 0.3 m 3 /min/m 2 (1 ft 3 /min/ft 2 ) of floor area,with suction taken from a point within 300 mm (12 in.)of floor level

2 2Up to 450 mm (18 in.) above floor level of the room,except as noted below, for entire floor area

Unclassified Unclassified

Up to 450 mm (18 in.) above floor level of the roomwhere room is provided with ventilation of at least 0.3

m 3 /min/m 2 (1 ft 3 /min/ft 2 ) of floor area, withsuction taken from a point within 300 mm (12 in.) offloor level

2 2Within 0.9 m (3 ft) of any fill or dispensing point,extending in all directions

Specific areas adjacentto classified locations


Areas adjacent to classified locations whereflammable vapors are not likely to be released, suchas stock rooms, switchboard rooms, and other similarlocations, where mechanically ventilated at a rate offour or more air changes per hour or designed withpositive air pressure or where effectively cut off bywalls or partitions

Repair garage,minor (where Class Iliquids or gaseous fuelsare not transferred ordispensed1)

2 2Entire space within any pit, belowgrade work area, orsubfloor work area that is not ventilated

2 2

Up to 450 mm (18 in.) above floor level, extending 0.9m (3 ft) horizontally in all directions from opening toany pit, belowgrade work area, or subfloor work areathat is not ventilated


Entire space within any pit, belowgrade work area, orsubfloor work area that is provided with ventilation of

at least 0.3 m 3 /min/m 2 (1 ft 3 /min/ft 2 ) of floor area,with suction taken from a point within 300 mm (12 in.)of floor level


192 of 270 4/16/2015 11:12 AM

Location

Class I

Extent of Classified Location

Division

(Group D)

Zone

(GroupIIA)

Specific areas adjacentto classified locations


Areas adjacent to classified locations whereflammable vapors are not likely to be released, suchas stock rooms, switchboard rooms, and other similarlocations, where mechanically ventilated at a rate offour or more air changes per hour or designed withpositive air pressure, or where effectively cut off bywalls or partitions

*Includes draining of Class I liquids from vehicles.

(1) Floor Areas.

(0) Ventilation Provided. The floor area shall be unclassified where there is mechanical ventilation

providing a minimum of four air changes per hour or 0.3 m 3 /min/m 2 (1 cfm/ft 2 ) of exchangedair for each square meter (foot) of floor area. Ventilation shall provide for air exchange across theentire floor area, and exhaust air shall be taken at a point within 0.3 m (12 in.) of the floor.

(0) Ventilation Not Provided. The entire floor area up to a level of 450 mm (18 in.) above the floorshall be classified as Class I, Division 2 if the ventilation does not comply with 511.3(C)(1)(a) .

(1) Ceiling Areas.

Where lighter-than-air gaseous fueled vehicles, such as vehicles fueled by natural gas or hydrogen, arerepaired or stored, the area within 450 mm (18 in.) of the ceiling shall be considered for classification inaccordance with (a) and (b).

(0) Ventilation Provided . The ceiling area shall be unclassified where ventilation is provided, from apoint not more than 450 mm (18 in.) from the highest point in the ceiling, to exhaust the ceiling

area at a rate of not less than 0.3 m 3 /min/m 2 (1 cfm/ft 2 ) of ceiling area at all times that thebuilding is occupied or when vehicles using lighter-than-air gaseous fuels are parked below thisarea.

(0) Ventilation Not Provided. Ceiling areas that are not ventilated in accordance with 511.3(C)(2)(a)shall be classified as Class I, Division 2.

(1) Pit Areas in Lubrication or Service Room.

Any pit, belowgrade work area, or subfloor work area shall be classified as provided in (a) or (b).

(0) Ventilation Provided. The pit area shall be a Class I, Division 2 location where there ismechanical ventilation providing a minimum of six air changes per hour.

(0) Ventilation Not Provided. Where ventilation is not provided in accordance with 511.3(C)(3)(a) ,any pit or depression below floor level shall be a Class I, Division 1 location that extends up to thefloor level.




Street Address:

City:

State:

Zip:



193 of 270 4/16/2015 11:12 AM

Committee Statement

CommitteeStatement:

In order to align with NFPA 30A-2015, 511.3(C) is replaced in its entirety with a new 511.3(C)covering both major and minor repair garages where heavier than air gaseous Class I liquids aretransferred or dispensed. The new Table 511.3(C) is a replica of the corresponding portion of Table8.3.2 of NFPA 30A in order to comply with the NEC Style Manual with regards to internal referencesthat exist within the NFPA 30A table. An informational note was added to refer back to the originaltable in NFPA 30A.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


194 of 270 4/16/2015 11:12 AM

First Revision No. 3955-NFPA 70-2015 [ Section No. 511.3(D) ]

(D) Minor Repair Garages, Major .

Where flammable liquids having a flash point below 38°C (100°F) such as gasoline, or gaseous fuelssuch as natural gas or hydrogen, will not be dispensed or transferred, the classification rules in (D)(1),(D)(2), and (D)(3) shall apply to the lubrication and service rooms. Where vehicles using lighter-than-airgaseous fuels (such as hydrogen and natural gas) are repaired or stored, hazardous area classificationguidance is found in Table 511.3(D) .

Informational Note: For additional information see NFPA 30A -2015, Code for Motor FuelDispensing Facilities and Repair Garages , Table 8.3.2.

Table 511.3(D) Extent of Classified Locations for Major Repair Garages with Lighter-than-Air Fuel

Location

Class I

Extent of Classified LocationDivision 2 Zone 3

Repair garage,major

(where lighter-than-air gaseous

fueled 1 vehiclesare repaired orstored)

2 2 Within 450 mm (18 in.) of ceiling, except as noted below


Within 450 mm (18 in.) of ceiling where ventilation of at

least 0.3 m 3 /min/m 2 (1 ft 3 /min/ft 2 ) of floor area, withsuction taken from a point within 450 mm (18 in.) of thehighest point in the ceiling

Specific areasadjacent toclassified locations


Areas adjacent to classified locations where flammablevapors are not likely to be released, such as stock rooms,switchboard rooms, and other similar locations, wheremechanically ventilated at a rate of four or more airchanges per hour or designed with positive air pressure,or where effectively cut off by walls or partitions

1 Includes fuels such as hydrogen and natural gas, but not LPG.

2 For hydrogen (lighter than air) Group B, or natural gas Group D.

3 For hydrogen (lighter than air) Group IIC or IIB+H2, or natural gas Group IIA.

(1) Floor Areas.

Floor areas in minor repair garages without pits, belowgrade work areas, or subfloor work areas shall beunclassified. Where floor areas include pits, belowgrade work areas, or subfloor work areas inlubrication or service rooms, the classification rules in (a) or (b) shall apply.

(0) Ventilation Provided. The entire floor area shall be unclassified where there is mechanical

ventilation providing a minimum of four air changes per hour or 0.3 m 3 /min/m 2 (1 cfm/ft 2 ) ofexchanged air for each square meter (foot) of floor area. Ventilation shall provide for air exchangeacross the entire floor area, and exhaust air shall be taken at a point within 0.3 m (12 in.) of thefloor.

(0) Ventilation Not Provided. The floor area up to a level of 450 mm (18 in.) above any unventilatedpit, belowgrade work area, or subfloor work area and extending a distance of 900 mm (3 ft)horizontally from the edge of any such pit, belowgrade work area, or subfloor work area, shall beclassified as Class I, Division 2.

(1) Ceiling Areas.

Where lighter-than-air gaseous fuels (such as natural gas or hydrogen) will not be transferred, suchlocations shall be unclassified.


195 of 270 4/16/2015 11:12 AM

(1) Pit Areas in Lubrication or Service Room.

Any pit, belowgrade work area, or subfloor work area shall be classified as provided in (a) or (b).

(0) Ventilation Provided. Where ventilation is provided to exhaust the pit area at a rate of not less

than 0.3 m 3 /min/m 2 (1 cfm/ft 2 ) of floor area at all times that the building is occupied, or whenvehicles are parked in or over this area and where exhaust air is taken from a point within 300 mm(12 in.) of the floor of the pit, belowgrade work area, or subfloor work area, the pit shall beunclassified. [ 30A: 7.4.5.4. Table 8.3.1]

(0) Ventilation Not Provided. Where ventilation is not provided in accordance with 511.3(D)(3)(a) ,any pit or depression below floor level shall be a Class I, Division 2 location that extends up to thefloor level.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

In order to align with NFPA 30A-2015, 511.3(D) is replaced in its entirety with a new 511.3(D)covering major repair garages where vehicles using lighter than air gaseous fuels are repaired orstored. The new Table 511.3(D) is a replica of the corresponding portion of Table 8.3.2 of NFPA 30Ain order to comply with the NEC Style Manual with regards to internal references that exist within theNFPA 30A table. An informational note was added to refer back to the original table in NFPA 30A.Notes were added to the table to apply the correct groups for hydrogen applications.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.


196 of 270 4/16/2015 11:12 AM

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


197 of 270 4/16/2015 11:12 AM


(2) Alcohol-Based Windshield Washer Fluid.

The area used for storage, handling, or dispensing into motor vehicles of alcohol-based windshieldwasher fluid in repair garages shall be unclassified unless otherwise classified by a provision of 511.3.[30A:8.3.5 8.3.1 , Exception]




Street Address:

City:

State:

Zip:


Committee Statement


Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan


198 of 270 4/16/2015 11:12 AM

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


199 of 270 4/16/2015 11:12 AM

First Revision No. 3994-NFPA 70-2015 [ New Section after 511.7 ]

511.8 Underground Wiring.

Underground wiring shall be installed in threaded rigid metal conduit or intermediate metal conduit.

Exception: Type PVC conduit, Type RTRC conduit, and Type HDPE conduit shall be permitted whereburied under not less than 600 mm (2 ft) of cover. Where Type PVC conduit, Type RTRC conduit, orType HDPE conduit is used, threaded rigid metal conduit or threaded steel intermediate metal conduitshall be used for the last 600 mm (2 ft) of the underground run to emergence or to the point ofconnection to the aboveground raceway, and an equipment grounding conductor shall be included toprovide electrical continuity of the raceway system and for grounding of non–current-carrying metalparts.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

This new section clarifies that Type PVC conduit, Type RTRC conduit, and Type HDPE conduitcan be used where buried under not less than 2 ft of cover under a commercial garage. From thepoint of being under less than 2 ft of cover to where the conduit run terminates, the wiring methodsset forth in Article 511 apply.

ResponseMessage:

Public Input No. 1575-NFPA 70-2014 [New Section after 511.7(B)(1)]

Ballot Results


16 Eligible Voters

1 Not Returned

11 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All

Ankele, Donald W.

Blais, Steven J.

Burns, Dave


200 of 270 4/16/2015 11:12 AM

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Wechsler, David B.


Bernsen, Marc J.

Where PVC,RTRC and HDPE are used and buried under not less than 2 ft of cover. The requirment to beencased in 2" of concrete should be retained. There are locations in the mining and logging industies where acommercial garage may not have a concrete floor.

Wirfs, Mark C.

NONE>



Agree with John L Simmons comments.

Simmons, John L.

This new section will in some cases create unsafe conditions. The scope of Article 511 includes areas whererepairs are made. This would include areas where repairs are made in spaces without concrete floors. The use ofnonmetallic conduit in an area without a concrete floor and where heavy equipment is being repaired mayintroduce an unsafe condition in which the raceway may be broken due to the weight of the equipment and/orequipment that operates by traveling on tracks.


201 of 270 4/16/2015 11:12 AM

First Revision No. 3926-NFPA 70-2015 [ Definitions (513.2): Mobile Equi... to Portable

Eq... ]

Mobile Equipment.

Equipment with electrical components suitable to be moved only with mechanical aids or is provided withwheels for movement by person(s) or powered devices.

Portable Equipment (as applied to Article 513) .

Equipment with electrical components suitable to be moved by a single person without mechanical aids.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Both terms are used throughout the NEC and should be relocated to Article 100 inaccordance with the NEC Style Manual.

ResponseMessage:

Public Input No. 1807-NFPA 70-2014 [Definition: Mobile Equipment.]

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


202 of 270 4/16/2015 11:12 AM


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


203 of 270 4/16/2015 11:12 AM



204 of 270 4/16/2015 11:12 AM

(1) Class I Locations.


205 of 270 4/16/2015 11:12 AM

Table 514.3(B)(1) shall be applied where Class I liquids are stored, handled, or dispensed and shall beused to delineate and classify motor fuel dispensing facilities and commercial garages as defined in Article511. Table 515.3 shall be used for the purpose of delineating and classifying aboveground tanks. A ClassI location shall not extend beyond an unpierced wall, roof, or other solid partition. [30A:8.1, 8.2, 8.3]

Table 514.3(B)(1) Class I Locations — Motor Fuel Dispensing Facilities

LocationDivision

(Group D)Zone

(Group IIA) Extent of Classified Location1

Dispensing Device (except

Overhead Type) 2, 3

Under dispensercontainment

1 1Entire space within and under dispenser pit orcontainment

Dispenser 2 2

Within 450 mm (18 in.) of dispenser enclosure orthat portion of dispenser enclosure containingliquid handling liquid-handling components,extending horizontally in all directions and downto grade level

Outdoor 2 2Up to 450 mm (18 in.) above grade level,extending 6 m (20 ft) horizontally in all directionsfrom dispenser enclosure

Indoor

- with mechanical ventilation 2 2Up to 450 mm (18 in.) above floor level,extending 6 m (20 ft) horizontally in all directionsfrom dispenser enclosure

- with gravity ventilation 2 2Up to 450 mm (18 in.) above floor level,extending 7.5 m (25 ft) horizontally in alldirections from dispenser enclosure

Dispensing Device —

Overhead Type4 1 1Space within dispenser enclosure and allelectrical equipment integral with dispensinghose or nozzle

2 2Within 450 mm (18 in.) of dispenser enclosure,extending horizontally in all directions and downto grade level

2 2

Up to 450 mm (18 in.) above grade level,extending 6 m (20 ft) horizontally in all directionsfrom a point vertically below edge of dispenserenclosure

Remote Pump —

Outdoor 1 1Entire space within any pit or box below gradelevel, any part of which is within 3 m (10 ft)horizontally from any edge of pump

2 2Within 900 mm (3 ft) of any edge of pump,extending horizontally in all directions

2 2Up to 450 mm (18 in.) above grade level,extending 3 m (10 ft) horizontally in all directionsfrom any edge of pump

Indoor 1 1 Entire space within any pit

2 2Within 1.5 m (5 ft) of any edge of pump,extending in all directions

2 2Up to 900 mm (3 ft) above floor level, extending7.5 m (25 ft) horizontally in all directions fromany edge of pump

Sales, Storage, RestRooms including structures(such as the attendant’skiosk) on or adjacent to

unclassified unclassified Except as noted below


206 of 270 4/16/2015 11:12 AM

LocationDivision

(Group D)Zone


1 1Entire volume, if there is any opening to roomwithin the extent of a Division 1 or Zone 1location

2 2Entire volume, if there is any opening to roomwithin the extent of a Division 2 or Zone 2location

Tank, Aboveground

Inside tank 1 0 Entire inside volume

Shell, ends, roof, dike area 1 1

Entire space within dike, where dike heightexceeds distance from tank shell to inside of dikewall for more than 50 percent of tankcircumference

2 2

Entire space within dike, where dike height doesnot exceed distance from tank shell to inside ofdike wall for more than 50 percent of tankcircumference

Vent 2 2 Within 3 m (10 ft) of shell, ends, or roof of tank

1 1Within 1.5 m (5 ft) of open end of vent, extendingin all directions

2 2Between 1.5 m and 3 m (5 ft and 10 ft) fromopen end of vent, extending in all directions

Tank, Underground

Inside tank 1 0 Entire inside volume

Fill Opening 1 1

Entire space within any pit or box below gradelevel, any part of which is within a Division 1 orDivision 2 classified location or within a Zone 1or Zone 2 classified location

2 2

Up to 450 mm (18 in.) above grade level,extending 1.5 m (5 ft) horizontally in all directionsfrom any tight-fill connection and extending 3 m(10 ft) horizontally in all directions from anyloose-fill connection

Vent 1 1Within 1.5 m (5 ft) of open end of vent, extendingin all directions

2 2Between 1.5 m and 3 m (5 ft and 10 ft) fromopen end of vent, extending in all directions

Vapor Processing System

Pits 1 1

Entire space within any pit or box below gradelevel, any part of which: (1) is within a Division 1or Division 2 classified location; (2) is within aZone 1 or Zone 2 classified location; (3) housesany equipment used to transfer or processvapors

Equipment in protectiveenclosures

2 2 Entire space within enclosure

Equipment not withinprotective enclosure

2 2

Within 450 mm (18 in.) of equipment containingflammable vapors or liquid, extendinghorizontally in all directions and down to gradelevel

2 2Up to 450 mm (18 in.) above grade level within 3m (10 ft) horizontally of the vapor processingequipment


207 of 270 4/16/2015 11:12 AM

LocationDivision

(Group D)Zone


- Equipment enclosure 1 1Entire space within enclosure, if flammable vaporor liquid is present under normal operatingconditions

2 2Entire space within enclosure, if flammable vaporor liquid is not present under normal operatingconditions

- Vacuum assist blower 2 2Within 450 mm (18 in.) of blower, extendinghorizontally in all directions and down to gradelevel

2 2Up to 450 mm (18 in.) above grade level,extending 3 m (10 ft) horizontally in all directions

Vault 1 1Entire interior space, if Class I liquids are storedwithin

1For marine application, grade level means the surface of a pier, extending down to water level.

2Refer to Figure 514.3(a) and Figure 514.3(b) for an illustration of classified location around dispensingdevices.

3Area classification inside the dispenser enclosure is covered in UL 87, Standard for Power-OperatedDispensing Devices for Petroleum Products.

4Ceiling-mounted hose reel. [30A:Table 8.3.1]




Street Address:

City:

State:

Zip:


Committee Statement


Response Message:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey


208 of 270 4/16/2015 11:12 AM

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


209 of 270 4/16/2015 11:12 AM

First Revision No. 4002-NFPA 70-2015 [ New Section after 514.3(B)(2) ]

(3) Fuel Storage.

(a) Aboveground tanks storing CNG or LNG shall be separated from any adjacent property line that isor can be built upon, any public way, and the nearest important building on the same property.[ 30A: 12.3.1]

Informational Note: The relevant distances are given in Section 8.4 of NFPA 52 -2013,Vehicular Gaseous Fuel Systems Code .

(b) Aboveground tanks storing hydrogen shall be separated from any adjacent property line that is orcan be built upon, any public way, and the nearest important building on the same property.[ 30A: 12.3.2]

Informatonal Note: The relevant distances given in NFPA 2 -2011, HydrogenTechnologies Code .

(c) Aboveground tanks storing LP-Gas shall be separated from any adjacent property line that is orcan be built upon, any public way, and the nearest important building on the same property.[ 30A: 12.3.3]

Informational Note: The relevant distances are given in Section 6.3 of NFPA 58 -2014,Liquefied Petroleum Gas Code .

(d) Aboveground tanks storing CNG, LNG, or LP-Gas shall be separated from each other by at least6 m (20 ft) and from dispensing devices that dispense liquid or gaseous motor vehicle fuels by atleast 6 m (20 ft). [ 30A: 12.3.3]

Exception No. 1: The required separation shall not apply to tanks or dispensers storing orhandling fuels of the same chemical composition.

Exception No. 2: The required separation shall not apply when both the gaseous fuel storageand dispensing equipment are at least 15 m (50 ft) from any other aboveground motor fuelstorage or dispensing equipment.

Informational Note: For further information, see NFPA 52 -2013, Vehicular Gaseous FuelSystems Code , or NFPA 58 -2014, Liquefied Petroleum Gas Code , as applicable.

(e) Dispenser Installations Beneath Canopies. Where CNG or LNG dispensers are installed beneatha canopy or enclosure, either the canopy or enclosure shall be designed to prevent accumulationor entrapment of ignitible vapors or all electrical equipment installed beneath the canopy orenclosure shall be suitable for Class I, Division 2 hazardous (classified) locations. [ 30A: 12.4]

(f) Specific Requirements for LP-Gas Dispensing Devices. [ 30A: 12.5] Dispensing devices forLP-Gas shall be located as follows:

(1) At least 3 m (10 ft) from any dispensing device for Class I liquids

(2) At least 1.5 m (5 ft) from any dispensing device for Class I liquids where the followingconditions exist:

a. The LP-Gas deliver nozzle and filler valve release no more than 4 cm 3 (0.1 oz) ofliquid upon disconnection.

b. The fixed maximum liquid level gauge remains closed during the entire refuelingprocess. [ 30A: 12.5.2]

Table 514.3(B)(2) shall be used to delineate and classify areas for the purpose of installation ofelectrical wiring and electrical utilization equipment.



210 of 270 4/16/2015 11:12 AM



Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

A new 514.3(B)(3) contains area classification information for compressed gas fuel storageand is extracted from NFPA 30A.

ResponseMessage:

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


211 of 270 4/16/2015 11:12 AM



212 of 270 4/16/2015 11:12 AM

(2) Compressed Natural Gas, Liquefied Natural Gas, and Liquefied Petroleum Gas Areas.


213 of 270 4/16/2015 11:12 AM

Table 514.3(B)(2)shall be used to delineate and classify areas where compressed natural gas (CNG),liquefied natural gas (LNG), or liquefied petroleum gas (LPG) is stored, handled, or dispensed. WhereCNG or LNG dispensers are installed beneath a canopy or enclosure, either the canopy or the enclosureshall be designed to prevent accumulation or entrapment of ignitible vapors, or all electrical equipmentinstalled beneath the canopy or enclosure shall be suitable for Class I, Division 2 hazardous (classified)locations. Dispensing devices for liquefied petroleum gas shall be located not less than 1.5 m (5 ft) fromany dispensing device for Class I liquids. [ 30A: 12.1, 12.4, 12.5] shall be used to delineate and classifyareas where CNG, LNG, compressed or liquefied hydrogen, LP-Gas, or combinations of these, aredispensed as motor vehicle fuels along with Class I or Class II liquids that are also dispensed as motorvehicle fuels. [ 30A: 12.1]

Where CNG or LNG dispensers are installed beneath a canopy or enclosure, either the canopy orenclosure shall be designed to prevent accumulation or entrapment of ignitible vapors or all electricalequipment installed beneath the canopy or enclosure shall be suitable for Class I, Division 2 hazardous(classified) locations. [ 30A: 12.4]

Dispensing devices for LP-Gas shall be located as follows:

(1) At least 3 m (10 ft) from any dispensing device for Class I liquids

(2) At least 1.5 m (5 ft) from any dispensing device for Class I liquids where the following conditionsexist:

a. The LP-Gas deliver nozzle and filler valve release no more than 4 cm 3 (0.1 oz) of liquid upondisconnection.

b. The fixed maximum liquid level gauge remains closed during the entire refueling process.

[ 30A: 12.5.2]

Informational Note No. 1: For information on area classification where liquefied petroleum gasesare dispensed, see Applicable requirements for dispensing devices for LP-Gas is found in NFPA58-2014, Liquefied Petroleum Gas Code.

Informational Note No. 2: For information on classified areas pertaining to LP-Gas systems otherthan residential or commercial, see NFPA 58-2014, Liquefied Petroleum Gas Code, and NFPA59-2012, Utility LP-Gas Plant Code.

Informational Note No. 3: See 514.3(C) for motor fuel dispensing stations in marinas andboatyards.

Table 514.3(B)(2) Electrical Equipment Classified Areas for Dispensing Devices

DispensingDevice

Extent of Classified Area

Class I, Division 1 Class I, Division 2

Compressednatural gas(CNG)

Entire space within the dispenser enclosure1.5 m (5 ft) in all directionsfrom dispenser enclosure

Liquefiednatural gas(LNG)

Entire space within the dispenser enclosure and 1.5 m (5ft) in all directions from the dispenser enclosure

From 1.5 m to 3.0 m (5 ft to10 ft) in all directions from thedispenser enclosure 3 m (10ft) in all directions from thedispenser enclosure

Liquefiedpetroleum gas(LP-Gas)

Entire space within the dispenser enclosure; 450 mm (18in.) from the exterior surface of the dispenser enclosureto an elevation of 1.2 m (4 ft) above the base of thedispenser; the entire pit or open space beneath thedispenser and within 6.0 m (20 ft) horizontally from anyedge of the dispenser when the pit or trench is notmechanically ventilated. 450 mm (18 in.) from the exteriorsurface of the dispenser enclosure to an elevation of 1.22m (4 ft) above the base of the dispenser; the entire pit oropen space beneath the dispenser and within 6 m (20 ft)horizontally from any edge of the dispenser when the pitor trench is not mechanically ventilated

Up to 450 mm (18 in.)aboveground and within 6.0m (20 ft) Up to 450 mm (18in.) above ground and within6 m (20 ft) horizontally fromany edge of the dispenserenclosure, including pits ortrenches within this area whenprovided with adequatemechanical ventilation


214 of 270 4/16/2015 11:12 AM

[30A:Table 12.6.2]




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

To align with NFPA 30A-2015, 514.3(B)(2) is replaced in its entirety with a new 514.3(B)(2). Thenew Table 514.3(B)(2) is extracted from NFPA 30A Table 12.6.2 located in TIA 15-1.

Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


215 of 270 4/16/2015 11:12 AM


514.8 Underground Wiring.

Underground wiring shall be installed in threaded rigid metal conduit or threaded steel intermediate metalconduit. Any portion of electrical wiring that is below the surface of a Class I, Division 1, or a Class I,Division 2, location [as classified in Table 514.3(B)(1) and Table 514.3(B)(2)] shall be sealed within 3.05m (10 ft) of the point of emergence above grade. Except for listed explosionproof reducers at the conduitseal, there shall be no union, coupling, box, or fitting between the conduit seal and the point of emergenceabove grade. Refer to Table 300.5.

Exception No. 1: Type MI cable shall be permitted where it is installed in accordance with Article 332.

Exception No. 2: Type PVC conduit and , Type RTRC conduit, and Type HDPE conduit shall bepermitted where buried under not less than 600 mm (2 ft) of cover. Where Type PVC conduit or , TypeRTRC conduit, or Type HDPE conduit is used, threaded rigid metal conduit or threaded steelintermediate metal conduit shall be used for the last 600 mm (2 ft) of the underground run to emergenceor to the point of connection to the aboveground raceway, and an equipment grounding conductor shallbe included to provide electrical continuity of the raceway system and for grounding of non–current-carrying metal parts.




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

Type HDPE provides at least the same level of protection as Type PVC or Type RTRC whenburied 24 inches in the earth. This is also permitted in 353.10. Buried in earth at 24 inches is notin a classified location.

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey


216 of 270 4/16/2015 11:12 AM

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


217 of 270 4/16/2015 11:12 AM


(A) At Dispenser.

A listed seal shall be provided in each conduit run entering or leaving a dispenser or any cavities orenclosures in direct communication therewith. The sealing fitting or listed explosionproof reducer at theseal shall be the first fitting after the conduit emerges from the earth or concrete.




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: Listed explosionproof reducers were added to align with other sections.

Response Message:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy


218 of 270 4/16/2015 11:12 AM

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


219 of 270 4/16/2015 11:12 AM


514.11 Circuit Disconnects.

(A) General Emergency Electrical Disconnects .

Each circuit leading to or through dispensing equipment, including all associated power, communications,data, and video circuits, and equipment for remote pumping systems, shall be provided with a clearlyidentified and readily accessible switch or other approved means, located remote from the dispensingdevices, to disconnect simultaneously from the source of supply, all conductors of the circuits, includingthe grounded conductor, if any. Fuel dispensing systems shall be provided with one or more clearlyidentified emergency shutoff devices or electrical disconnects. Such devices or disconnects shall beinstalled in approved locations but not less than 6 m (20 ft) or more than 30 m (100 ft) from the fueldispensing devices that they serve. Emergency shutoff devices or electrical disconnects shall disconnectpower to all dispensing devices; to all remote pumps serving the dispensing devices; to all associatedpower, control, and signal circuits; and to all other electrical equipment in the hazardous (classified)locations surrounding the fuel dispensing devices. When more than one emergency shutoff device orelectrical disconnect is provided, all devices shall be interconnected. Resetting from an emergencyshutoff condition shall require manual intervention and the manner of resetting shall be approved by theauthority having jurisdiction. [ 30A: 6.7]

Single-pole breakers utilizing handle ties shall not be permitted.

Exception: Intrinsically safe electrical equipment need not meet this requirement. [ 30A: 6.7]

(B) Attended Self-Service Motor Fuel Dispensing Facilities.

Emergency controls as specified in 514.11(A) shall be installed at a location acceptable to the authorityhaving jurisdiction, but controls shall not be more than 30 m (100 ft) from dispensers. At attended motorfuel dispensing facilities, the devices or disconnects shall be readily accessible to the attendant.[30A:6.7.1]

(C) Unattended Self-Service Motor Fuel Dispensing Facilities.

Emergency controls as specified in 514.11(A) shall be installed at a location acceptable to the authorityhaving jurisdiction, but the control shall be more than 6 m (20 ft) but less than 30 m (100 ft) from thedispensers. Additional emergency controls shall be installed on each group of dispensers or the outdoorequipment used to control the dispensers. Emergency controls shall shut off all power to all dispensingequipment at the station. Controls shall be manually reset only in a manner approved by the authorityhaving jurisdiction. At unattended motor fuel dispensing facilities, the devices or disconnects shall bereadily accessible to patrons and at least one additional device or disconnect shall be readily accessibleto each group of dispensing devices on an individual island. [30A:6.7.2]

Informational Note: For additional information, see 6.7.1 and 6.7.2 of NFPA 30A -2012, Code forMotor Fuel Dispensing Facilities and Repair Garages .




Street Address:

City:

State:

Zip:


Committee Statement

Committee Statement: Section 514.11 is revised to reflect the requirements in NFPA 30A- 2015.

Response Message:



220 of 270 4/16/2015 11:12 AM


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


221 of 270 4/16/2015 11:12 AM



222 of 270 4/16/2015 11:12 AM

515.3 Class I Locations.


223 of 270 4/16/2015 11:12 AM

Table 515.3 shall be applied where Class I liquids are stored, handled, or dispensed and shall be used todelineate and classify bulk storage plants. The class location shall not extend beyond a floor, wall, roof, orother solid partition that has no communicating openings. [30:8.1, 8.2.2 7.3, 7.4 ]

Informational Note No. 1: The area classifications listed in Table 515.3 are based on the premisethat the installation meets the applicable requirements of NFPA 30-2012 2015 , Flammable andCombustible Liquids Code, Chapter 5, in all respects. Should this not be the case, the authorityhaving jurisdiction has the authority to classify the extent of the classified space.

Informational Note No. 2: See 555.21 514.3(C) through (E) for gasoline dispensing stations inmarinas and boatyards.

Table 515.3 Electrical Area Classifications

LocationNEC Class I

DivisionZone Extent of Classified Area

Indoor equipment installed inaccordance with Section 5.3 7.3of NFPA 30 where flammablevapor–air mixtures can existunder normal operation

1 0

The entire area associated with suchequipment where flammable gases or vaporsare present continuously or for long periods oftime

1 1Area within 1.5 m (5 ft) of any edge of suchequipment, extending in all directions

2 2

Area between 1.5 m and 2.5 m (5 ft and 8 ft) ofany edge of such equipment, extending in alldirections; also, space up to 900 mm (3 ft)above floor or grade level within 1.5 m to 7.5 m(5 ft to 25 ft) horizontally from any edge of such

equipment1

Outdoor equipment of the typecovered in Section 5.3 7.3 ofNFPA 30 where flammablevapor–air mixtures may can existunder normal operation

1 0

The entire area associated with suchequipment where flammable gases or vaporsare present continuously or for long periods oftime

1 1Area within 900 mm (3 ft) of any edge of suchequipment, extending in all directions

2 2

Area between 900 mm (3 ft) and 2.5 m (8 ft) ofany edge of such equipment, extending in alldirections; also, space up to 900 mm (3 ft)above floor or grade level within 900 mm to 3.0m (3 ft to 10 ft) horizontally from any edge ofsuch equipment

Tank storage installations insidebuildings

1 1 All equipment located below grade level

2 2 Any equipment located at or above grade level

Tank — aboveground, fixed roof 1 0 Inside fixed roof tank

1 1Area inside dike where dike height is greaterthan the distance from the tank to the dike formore than 50 percent of the tank circumference

Shell, ends, or roof and dike area 2 2Within 3.0 m (10 ft) from shell, ends, or roof oftank; also, area inside dike to level of top ofdike wall

Vent 1 0 Area inside of vent piping or opening

1 1Within 1.5 m (5 ft) of open end of vent,extending in all directions

2 2Area between 1.5 m and 3.0 m (5 ft and 10 ft)from open end of vent, extending in alldirections


224 of 270 4/16/2015 11:12 AM

LocationNEC Class I


Tank — aboveground, floatingroof

Floating roof with With fixed outerroof

1 0Area between the floating and fixed roofsections and within the shell

Floating roof with With no fixedouter roof

1 1 Area above the floating roof and within the shell

Tank vault — interior 1 1Entire interior volume, if Class I liquids arestored within

Underground tank fill opening 1 1Any pit, box, or space below grade level, if anypart is within a Division 1 or 2, or Zone 1 or 2,classified location

2 2

Up to 450 mm (18 in.) above grade level withina horizontal radius of 3.0 m (10 ft) from a loosefill connection, and within a horizontal radius of1.5 m (5 ft) from a tight fill connection

Vent — discharging upward 1 0 Area inside of vent piping or opening

1 1Within 900 mm (3 ft) of open end of vent,extending in all directions

2 2Area between 900 mm and 1.5 m (3 ft and 5 ft)of open end of vent, extending in all directions

Drum and container filling —outdoors or indoors

1 0 Area inside the drum or container

1 1Within 900 mm (3 ft) of vent and fill openings,extending in all directions

2 2

Area between 900 mm and 1.5 m (3 ft and 5 ft)from vent or fill opening, extending in alldirections; also, up to 450 mm (18 in.) abovefloor or grade level within a horizontal radius of3.0 m (10 ft) from vent or fill opening

Pumps, bleeders, withdrawalfittings

Indoors Indoor 2 2

Within 1.5 m (5 ft) of any edge of such devices,extending in all directions; also, up to 900 mm(3 ft) above floor or grade level within 7.5 m (25ft) horizontally from any edge of such devices

Outdoors Outdoor 2 2

Within 900 mm (3 ft) of any edge of suchdevices, extending in all directions. Also, up to450 mm (18 in.) above grade level within 3.0 m(10 ft) horizontally from any edge of suchdevices

Pits and sumps

Without mechanical ventilation 1 1Entire area within a pit or sump if any part iswithin a Division 1 or 2, or Zone 1 or 2,classified location

With adequate mechanicalventilation

2 2Entire area within a pit or sump if any part iswithin a Division 1 or 2, or Zone 1 or 2,classified location

Containing valves, fittings, orpiping, and not within a Division 1or 2, or Zone 1 or 2, classifiedlocation

2 2 Entire pit or sump


225 of 270 4/16/2015 11:12 AM

LocationNEC Class I


Drainage ditches, separators,impounding basins

Outdoors Outdoor 2 2

Area up to 450 mm (18 in.) above ditch,separator, or basin; also, area up to 450 mm(18 in.) above grade within 4.5 m (15 ft)horizontally from any edge

Indoors Indoor Same classified area as pits and sumps

Tank vehicle and tank car 2

Tank vehicle and tank car 2

loading Loading through opendome

1 0 Area inside of the tank

1 1Within 900 mm (3 ft) of edge of dome,extending in all directions

2 2Area between 900 mm and 4.5 m (3 ft and 15ft) from edge of dome, extending in alldirections

Loading through bottomconnections with atmosphericventing

1 0 Area inside of the tank

1 1Within 900 mm (3 ft) of point of venting toatmosphere, extending in all directions

2 2

Area between 900 mm and 4.5 m (3 ft and 15ft) from point of venting to atmosphere,extending in all directions; also, up to 450 mm(18 in.) above grade within a horizontal radiusof 3.0 m (10 ft) from point of loading connection

Office and rest rooms Unclassified

If there is any opening to these rooms withinthe extent of an indoor classified location, theroom shall be classified the same as if the wall,curb, or partition did not exist.

Loading through closed domewith atmospheric venting

1 1Within 900 mm (3 ft) of open end of vent,extending in all directions

2 2

Area between 900 mm and 4.5 m (3 ft and 15ft) from open end of vent, extending in alldirections; also, within 900 mm (3 ft) of edge ofdome, extending in all directions

Loading through closed domewith vapor control

2 2Within 900 mm (3 ft) of point of connection ofboth fill and vapor lines extending in alldirections

Bottom loading with vapor controlor any bottom unloading

2 2

Within 900 mm (3 ft) of point of connections,extending in all directions; also up to 450 mm(18 in.) above grade within a horizontal radiusof 3.0 m (10 ft) from point of connections

Storage and repair garage fortank vehicles

1 1 All pits or spaces below floor level

2 2Area up to 450 mm (18 in.) above floor or gradelevel for entire storage or repair garage

Garages for other than tankvehicles

Unclassified Ordinary

If there is any opening to these rooms withinthe extent of an outdoor classified location, theentire room shall be classified the same as thearea classification at the point of the opening.

Outdoor drum storage Unclassified Ordinary


226 of 270 4/16/2015 11:12 AM

LocationNEC Class I


Inside rooms or storage lockersused for the storage of Class Iliquids

2 2 Entire room or locker

Indoor warehousing where thereis no flammable liquid transfer

Unclassified Ordinary

If there is any opening to these rooms withinthe extent of an indoor classified location, theroom shall be classified classified locationshall extend through the opening to the sameextent as if the wall, curb, or partition did notexist.

Office and rest rooms Ordinary

If there is any opening to these rooms withinthe extent of an indoor classified location, theroom shall be classified the same as if the wall,curb, or partition did not exist.

Piers and wharves See Figure 515.3.

1The release of Class I liquids may can generate vapors to the extent that the entire building, andpossibly an area surrounding it, should be considered a Class I, Division 2 or Zone 2 location.

2When classifying extent of area, consideration shall be given to the fact that tank cars or tank vehiclesmay can be spotted at varying points. Therefore, the extremities of the loading or unloading positionsshall be used. [30: Table 8.2.2 7.3.3 ]

Figure 515.3 Area Classification for a Marine Terminal Handling Flammable Liquids. [30:Figure29.3.22]



515.3_3953_BC.docx




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

The reference in Informational Note No. 2 was changed to provide a more direct reference.Section 555.21 referred the user back to 514.3(C) through (E).


227 of 270 4/16/2015 11:12 AM

The extracts were updated. (First para. 30:7.3, 7.4; Table replaced with 30:Table 7.3.3)

ResponseMessage:


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


228 of 270 4/16/2015 11:12 AM

First Revision No. 3956-NFPA 70-2015 [ Article 516 ]

Article 516 Spray Application, Dipping, Coating, and Printing Processes Using Flammable orCombustible Materials

Informational Note: Text that is followed by a reference in brackets has been extracted from NFPA33-2011 2015 , Standard for Spray Application Using Flammable and Combustible Materials, orNFPA 34-2011 2015 , Standard for Dipping, Coating, and Printing Processes Using Flammable orCombustible Liquids. Only editorial changes were made to the extracted text to make it consistentwith this Code.

Part I. General

516.1 Scope.

This article covers the regular or frequent application of flammable liquids, combustible liquids, andcombustible powders by spray operations and the application of flammable liquids, or combustible liquidsat temperatures above their flashpoint, by spraying, by dipping, coating, printing, or other means.

Informational Note: For further information regarding safeguards for these processes, such as fireprotection, posting of warning signs, and maintenance, see NFPA 33-2011 2015 , Standard forSpray Application Using Flammable and Combustible Materials, and NFPA 34-2011 2015 ,Standard for Dipping, Coating, and Printing Processes Using Flammable or Combustible Liquids.For additional information regarding ventilation, see NFPA 91-2010, Standard for Exhaust Systemsfor Air Conveying of Vapors, Gases, Mists, and Noncombustible Particulate Solids.

516.2 Definitions.

For the purpose of this article, the following definitions shall apply.

Flash-Off Area.

An open or enclosed area after a spray application process where vapors are released due to exposureto ambient air or a heated atmosphere. [ 33: 3.3.1.1]

Limited Finishing Workstation.

An apparatus that is capable of confining the vapors, mists, residues, dusts, or deposits that aregenerated by a spray application process and that meets the requirements of Section 14.3 of NFPA 33,Standard for Spray Application Using Flammable or Combustible Materials , but does not meet therequirements of a spray booth or spray room, as herein defined. [ 33: 3.3.15.1] An apparatus that iscapable of confining the vapors, mists, residues, dusts, or deposits that are generated by a sprayapplication process and that meets the requirements of Section 14.3 of NFPA 33 , Standard for SprayApplication Using Flammable or Combustible Materials , but does not meet the requirements of a spraybooth or spray room, as herein defined. [ 33: 3.3.18.1]

Outdoor Spray Area.

A spray area that is outside the confines of a building or that has a canopy or roof that does not limit thedissipation of the heat of a fire or dispersion of flammable vapors and does not restrict fire-fightingaccess and control. For the purpose of this standard, an outdoor spray area can be treated as anunenclosed spray area. [ 33: 3.3.2.3.1]

Resin Application Area.

Any area in which polyester resins or gelcoats are spray applied. [ 33: 3.3.1.2]


229 of 270 4/16/2015 11:12 AM

Spray Area.

Any fully enclosed, partly enclosed, or unenclosed area in which ignitible quantities of flammable orcombustible vapors, mists, residues, dusts, or deposits are present due to the operation of sprayprocesses, including (1) any area in the direct path of a spray application process; (2) the interior of aspray booth or spray room or limited finishing workstation, as herein defined; (3) the interior of anyexhaust plenum, eliminator section, or scrubber section; (4) the interior of any exhaust duct or exhauststack leading from a spray application process; (5) the interior of any air recirculation filter house orenclosure, including secondary recirculation particulate filters; (6) any solvent concentrator (pollutionabatement) unit or solvent recovery (distillation) unit. The following are not considered to be a part of thespray area: (1) fresh air make-up units; (2) air supply ducts and air supply plenums; (3) recirculation airsupply ducts downstream of secondary filters; (4) exhaust ducts from solvent concentrator (pollutionabatement) units. [ 33: 3.3.2.3]

Informational Note: Unenclosed spray areas are locations outside of buildings or are localizedoperations within a larger room or space. Such are normally provided with some local vaporextraction/ventilation system. In automated operations, the area limits are the maximum area in thedirect path of spray operations. In manual operations, the area limits are the maximum area ofspray when aimed at 90 degrees to the application surface.

Any fully enclosed, partly enclosed, or unenclosed area in which dangerous quantities of flammable orcombustible vapors, mists, residues, dusts, or deposits are present due to the operation of sprayprocesses, including (1) any area in the direct path of a spray application process; (2) the interior of aspray booth, spray room, or limited finishing workstation, as herein defined; (3) the interior of any exhaustplenum, eliminator section, or scrubber section; (4) the interior of any exhaust duct or exhaust stackleading from a spray application process; (5) the interior of any air recirculation path up to and includingrecirculation particulate filters; (6) any solvent concentrator (pollution abatement) unit or solvent recovery(distillation) unit; and (7) the inside of a membrane enclosure. The following are not part of the spray area:(1) fresh air make-up units; (2) air supply ducts and air supply plenums; (3) recirculation air supply ductsdownstream of recirculation particulate filters; and (4) exhaust ducts from solvent concentrator (pollutionabatement) units. [ 33: 3.3.2.3]

Informational Note: Unenclosed spray areas are locations outside of buildings or are localizedoperations within a larger room or space. Such are normally provided with some local vaporextraction/ventilation system. In automated operations, the area limits are the maximum area in thedirect path of spray operations. In manual operations, the area limits are the maximum area ofspray when aimed at 90 degrees to the application surface.

Spray Booth.

A power-ventilated enclosure for a spray application operation or process that confines and limits theescape of the material being sprayed, including vapors, mists, dusts, and residues that are produced bythe spraying operation and conducts or directs these materials to an exhaust system. [ 33: 3.3.14]

Informational Note: A spray booth is an enclosure or insert within a larger room used forspray/coating/dipping applications. A spray booth may be fully enclosed or have open front or faceand may include a separate conveyor entrance and exit. The spray booth is provided with adedicated ventilation exhaust but may draw supply air from the larger room or have a dedicated airsupply.

A power-ventilated enclosure for a spray application operation or process that confines and limits theescape of the material being sprayed, including vapors, mists, dusts, and residues that are produced bythe spraying operation and conducts or directs these materials to an exhaust system. [ 33: 3.3.15]

Informational Note: A spray booth is an enclosure or insert within a larger room used forspray/coating/dipping applications. A spray booth can be fully enclosed or have open front or faceand can include separate conveyor entrance and exit. The spray booth is provided with adedicated ventilation exhaust with supply air from the larger room or from a dedicated air supply.

Spray Room.

A power-ventilated fully enclosed room used exclusively for open spraying of flammable or combustiblematerials. A spray room is a purposefully enclosed room built for spray/coating/dipping applicationsprovided with dedicated ventilation supply and exhaust. Normally the room is configured to house theitem to be painted, providing reasonable access around the item/process. Depending on the size of theitem being painted, such rooms may actually be the entire building or the major portion thereof.[ 33: 3.3.15]

A power-ventilated fully enclosed room used exclusively for open spraying of flammable or combustiblematerials. [ 33: 3.3.16]


230 of 270 4/16/2015 11:12 AM

Unenclosed Spray Area.

Any spray area that is not confined by a limited finishing workstation, spray booth, or spray room, asherein defined. [ 33: 3.3.2.3.2]

Any spray area that is not confined by a limited finishing workstation, spray booth, or spray room, asherein defined. [ 33: 3.3.2.3.2]

516.3 Classification of Locations.

Classification is based on quantities of flammable vapors, combustible mists, residues, dusts, ordeposits that are present or might be present in quantities sufficient to produce ignitible or explosivemixtures with air.

(A) Zone Classification of Locations.

(0) For the purposes of this article, the zone system of electrical area classification shall be appliedas follows:

0. The inside of open or closed containers or vessels shall be considered a Class I, Zone 0location.

0. A Class I, Division 1 location shall be permitted to be alternatively classified as a Class I,Zone 1 location.

0. A Class I, Division 2 location shall be permitted to be alternatively classified as a Class I,Zone 2 location.

0. A Class II, Division 1 location shall be permitted to be alternatively classified as a Zone 21location.

0. A Class II, Division 2 location shall be permitted to be alternatively classified as a Zone 22location. [ 33: 6.2.2]

(0) For the purposes of electrical area classification, the division system and the zone system shallnot be intermixed for any given source of release. [ 33: 6.2.3]

(0) In instances of areas within the same facility classified separately, Class I, Zone 2 locations shallbe permitted to abut, but not overlap, Class I, Division 2 locations. Class I, Zone 0 or Zone 1locations shall not abut Class I, Division 1 or Division 2 locations. [ 33: 6.2.4]

(0) Open flames, spark-producing equipment or processes, and equipment whose exposed surfacesexceed the autoignition temperature of the material being sprayed shall not be located in a sprayarea or in any surrounding area that is classified as Division 2, Zone 2, or Zone 22.

Exception: This requirement shall not apply to drying, curing, or fusing apparatus. [ 33: 6.2.5]

(0) Any utilization equipment or apparatus that is capable of producing sparks or particles of hotmetal and that is located above or adjacent to either the spray area or the surrounding Division 2,Zone 2, or Zone 22 areas shall be of the totally enclosed type or shall be constructed to preventthe escape of sparks or particles of hot metal. [ 33: 6.2.6]

(B) Class I, Division 1 or Class I, Zone 0 Locations.

The following spaces shall be considered Class I, Division 1, or Class I, Zone 0, as applicable:

(0) The interior of any open or closed container or vessel of a flammable liquid

(0) The interior of any dip tank or coating tank

(0) The interior of any ink fountain, ink reservoir, or ink tank

Informational Note: For additional guidance, see Chapter 6 of NFPA 33-2011, Standardfor Spray Application Using Flammable or Combustible Materials , and Chapter 6 of NFPA34-2011, Standard for Dipping, Coating, and Printing Processes Using Flammable orCombustible Liquids .


231 of 270 4/16/2015 11:12 AM

(C) Class I, Division 1; Class I, Zone 1; Class II, Division 1; or Zone 21 Locations.

The following spaces shall be considered Class I, Division 1, or Class I, Zone 1, Class II, Division 1, orZone 21 locations, as applicable:

(0) The interior of spray booths and rooms except as specifically provided in 516.3(D)(7) .

(0) The interior of exhaust ducts.

(0) Any area in the direct path of spray operations.

(0) For open dipping and coating operations, all spaces within a 1.5-m (5-ft) radial distance from thevapor sources extending from these surfaces to the floor. The vapor source shall be the liquidexposed in the process and the drainboard, and any dipped or coated object from which it ispossible to measure vapor concentrations exceeding 25 percent of the lower flammable limit at adistance of 300 mm (1 ft), in any direction, from the object as in Figure 516.3(D)(1) .

(0) Sumps, pits, or belowgrade channels within 7.5 m (25 ft) horizontally of a vapor source. If thesump, pit, or channel extends beyond 7.5 m (25 ft) from the vapor source, it shall be provided witha vapor stop or it shall be classified as Class I, Division 1 for its entire length.

(0) All space in all directions outside of but within 900 mm (3 ft) of open containers, supplycontainers, spray gun cleaners, and solvent distillation units containing flammable liquids.

(0) For limited finishing workstations, the area inside the curtains or partitions. See Figure516.3(D)(5) .

(D) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 Locations.

The following spaces shall be considered Class I, Division 2; Class I, Zone 2; Class II, Division 2; orZone 22, as applicable.


232 of 270 4/16/2015 11:12 AM

(1) Unenclosed Spray Processes.

For unenclosed spraying, all space outside of but within 6 m (20 ft) horizontally and 3 m (10 ft) verticallyof the Class I, Division 1 or Class I, Zone 1 location as defined in 516.3(A) and not separated from itby partitions. See Figure 516.3(D)(1) . [ 33: 6.5.1]

Figure 516.3(D)(1) Electrical Area Classification for Unenclosed Spray Areas. [33:Figure 6.5.1]


233 of 270 4/16/2015 11:12 AM

(2) Closed-Top, Open-Face, and Open-Front Spray Booths and Spray Rooms.

If spray application operations are conducted within a closed-top, open-face, or open-front booth orroom, as shown in Figure 516.3(D)(2) , any electrical wiring or utilization equipment located outside ofthe booth or room but within 915 mm (3 ft) of any opening shall be suitable for Class I, Division 2; ClassI, Zone 2; Class II, Division 2; or Zone 22 locations, whichever is applicable. The Class I, Division 2;Class I, Zone 2; Class II, Division 2; or Zone 22 locations shown in Figure 516.3(D)(2) shall extendfrom the edges of the open face or open front of the booth or room in accordance with the following:

Informational Note: For both interlocked and non-interlocked exhaust ventilation systems, theDivision 2, Zone 2 or Zone 22 location extends 915 mm (3 ft) horizontally and 915 mm (3 ft)vertically from the open face or open front of the booth or room, as shown in Figure516.3(D)(2) .

Figure 516.3(D)(2) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 LocationsAdjacent to a Closed Top, Open Face, or Open Front Spray Booth or Room.

(3) Open-Top Spray Booths.

For spraying operations conducted within an open top spray booth, the space 915 mm (3 ft) verticallyabove the booth and within 915 mm (3 ft) of other booth openings shall be considered Class I, Division2; Class I, Zone 2; Class II, Division 2; or Zone 22. [ 33: 6.5.3]


234 of 270 4/16/2015 11:12 AM

(4) Enclosed Spray Booths and Spray Rooms.

For spraying operations confined to an enclosed spray booth or room, electrical area classification shallbe as follows: [ 33: 6.5.4]

(0) The area within 915 mm (3 ft) of any opening shall be classified as Class I, Division 2; Class I,Zone 2; Class II, Division 2; or Zone 22 locations, whichever is applicable, as shown in Figure516.3(D)(4)(1) .

(0) Where exhaust air is recirculated, both of the following shall apply:

0. The interior of any recirculation path from the secondary particulate filters up to andincluding the air supply plenum shall be classified as Class I, Division 2; Class I, Zone 2;Class II, Division 2; or Zone 22 locations, whichever is applicable.

0. The interior of fresh air supply ducts shall be unclassified.

(0) Where exhaust air is not recirculated, the interior of fresh air supply ducts and fresh air supplyplenums shall be unclassified.

Figure 516.3(D)(4)(1) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22Locations Adjacent to an Enclosed Spray Booth or Spray Room. [33:Figure 6.5.4]


235 of 270 4/16/2015 11:12 AM

(5) Limited Finishing Workstations.

For limited finishing workstations, the area inside the 915-mm (3-ft) space horizontally and verticallybeyond the volume enclosed by the outside surface of the curtains or partitions shall be classified asClass I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22, as shown in Figure 516.3(D)(5) .

Figure 516.3(D)(5) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 LocationsAdjacent to a Limited Finishing Workstation. [33:Figure 14.3.5.1]


236 of 270 4/16/2015 11:12 AM

(6) Areas Adjacent to Open Dipping and Coating Processes.


237 of 270 4/16/2015 11:12 AM

Electrical wiring and electrical utilization equipment located adjacent to open processes shall meet therequirements of 516.3(D)(6)(1) through (4) and Figure 516.3(D)(6)(a) , Figure 516.3(D)(6)(b) ,Figure 516.3(D)(6)(c) , Figure 516.3(D)(6)(d) , or Figure 516.3(D)(6)(e) , whichever is applicable.[ 34: 6.4]

(0) Electrical wiring and electrical utilization equipment located in any sump, pit, or below gradechannel that is within 7620 mm (25 ft) horizontally of a vapor source, as defined by this standard,shall be suitable for Class I, Division 1 or Class I, Zone 1 locations. If the sump, pit, or channelextends beyond 7620 mm (25 ft) of the vapor source, it shall be provided with a vapor stop, or itshall be classified as Class I, Division 1 or Class I, Zone 1 for its entire length. [ 34: 6.4.1]

(0) Electrical wiring and electrical utilization equipment located within 1525 mm (5 ft) of a vaporsource shall be suitable for Class I, Division 1 or Class I, Zone 1 locations. The space inside a diptank, ink fountain, ink reservoir, or ink tank shall be classified as Class I, Division 1 or Class I,Zone 0, whichever is applicable. [ 34: 6.4.2]

(0) Electrical wiring and electrical utilization equipment located within 915 mm (3 ft) of the Class I,Division 1 or Class I, Zone 1 location described in 516.3(D)(6)(2) shall be suitable for Class I,Division 2 or Class I, Zone 2 locations, whichever is applicable. [ 34: 6.4.3]

(0) The space 915 mm (3 ft) above the floor and extending 6100 mm (20 ft) horizontally in alldirections from the Class I, Division 1 or Class I, Zone 1 location described in 516.3(D)(6)(2)shall be classified as Class I, Division 2 or Class I, Zone 2, and electrical wiring and electricalutilization equipment located within this space shall be suitable for Class I, Division 2 or Class I,Zone 2 locations, whichever is applicable. [ 34: 6.4.4]

Exception: This space shall be permitted to be unclassified for purposes of electrical

installations if the surface area of the vapor source does not exceed 0.5 m 2 (5 ft 2 ), thecontents of the dip tank, ink fountain, ink reservoir, or ink tank do not exceed 19 L (5 gal), andthe vapor concentration during operating and shutdown periods does not exceed 25 percent ofthe lower flammable limit.

Figure 516.3(D)(6)(a) Electrical Area Classification for Open Dipping and Coating ProcessesWithout Vapor Containment or Ventilation. [34:Figure 6.4(a)]

Figure 516.3(D)(6)(b) Electrical Area Classification for Open Dipping and Coating Processeswith Peripheral Vapor Containment and Ventilation — Vapors Confined to Process Equipment.[34:Figure 6.4(b)]


238 of 270 4/16/2015 11:12 AM

Figure 516.3(D)(6)(c) Electrical Area Classification for Open Dipping and Coating Processeswith Partial Peripheral Vapor Containment and Ventilation — Vapors NOT Confined to ProcessEquipment. [34:Figure 6.4(c)]

Figure 516.3(D)(6)(d) Electrical Area Classification for Open Dipping and Coating Processeswith Partial Peripheral Vapor Containment and Ventilation — Vapors Confined to ProcessEquipment. [34:Figure 6.4(d)]


239 of 270 4/16/2015 11:12 AM

Figure 516.3(D)(6)(e) Electrical Area Classification for a Typical Printing Process. [34:Figure6.4(e)]


240 of 270 4/16/2015 11:12 AM

(7) Enclosed Coating and Dipping Operations.

Areas adjacent to enclosed dipping and coating processes shall be classified in accordance with516.3(D)(7) and Figure 516.3(D)(7) . The space adjacent to an enclosed dipping or coating process orapparatus shall be considered unclassified. [ 34: 6.5.3]

Exception: The space within 915 mm (3 ft) in all directions from any opening in the enclosures shallbe classified as Class I, Division 2 or Class I, Zone 2, as applicable. [34:6.5.2]

The interior of any enclosed dipping or coating process or apparatus shall be a Class I, Division 1 orClass I, Zone 1 location, and electrical wiring and electrical utilization equipment located within thisspace shall be suitable for Class I, Division 1 or Class I, Zone 1 locations, whichever is applicable. Thearea inside the dip tank shall be classified as Class I, Division 1 or Class I, Zone 0, whichever isapplicable. [ 34: 6.5.1]

Figure 516.3(D)(7) Electrical Area Classification Around an Enclosed Dipping or CoatingProcess. [34:Figure 6.5]

(8) Open Containers.

All space in all directions within 600 mm (2 ft) of the Division 1 or Zone 1 area surrounding opencontainers, supply containers, spray gun cleaners, and solvent distillation units containing flammableliquids, as well as the area extending 1.5 m (5 ft) beyond the Division 1 or Zone 1 area up to a height of460 mm (18 in.) above the floor or grade level. [ 33: 6.5.5]

(E) Adjacent Locations.

Adjacent locations that are cut off from the defined Class I or Class II locations by tight partitions withoutcommunicating openings, and within which flammable vapors or combustible powders are not likely tobe released, shall be unclassified.

(F) Unclassified Locations.

Locations using drying, curing, or fusion apparatus and provided with positive mechanical ventilationadequate to prevent accumulation of flammable concentrations of vapors, and provided with effectiveinterlocks to de-energize all electrical equipment (other than equipment identified for Class I locations) incase the ventilating equipment is inoperative, shall be permitted to be unclassified where the authorityhaving jurisdiction so judges.

Informational Note: For further information regarding safeguards, see NFPA 86 -2011,Standard for Ovens and Furnaces .

516.4 Wiring and Equipment in Class I Locations.

(A) Wiring and Equipment — Vapors.

All electrical wiring and equipment within the Class I location (containing vapor only — not residues)defined in 516.3 shall comply with the applicable provisions of Article 501 or Article 505 , asapplicable.

(B) Wiring and Equipment — Vapors and Residues.

Unless specifically listed for locations containing deposits of dangerous quantities of flammable orcombustible vapors, mists, residues, dusts, or deposits (as applicable), there shall be no electricalequipment in any spray area as herein defined whereon deposits of combustible residue may readilyaccumulate. All electrical wiring shall be comply with 516.4(A) .


241 of 270 4/16/2015 11:12 AM

(C) Illumination.


242 of 270 4/16/2015 11:12 AM

(0) Luminaires, like that shown in Figure 516.4(C)(1) , that are attached to the walls or ceiling of aspray area but that are outside any classified area and are separated from the spray area byglass panels shall be suitable for use in unclassified locations. Such fixtures shall be servicedfrom outside the spray area. [ 33: 6.6.1]

(0) Luminaires, like that shown in Figure 516.4(C)(1) , that are attached to the walls or ceiling of aspray area; that are separated from the spray area by glass panels and that are located within aClass I, Division 2; a Class I, Zone 2; a Class II, Division 2; or a Zone 22 location shall be suitablefor such location. Such fixtures shall be serviced from outside the spray area. [ 33: 6.6.2]

(0) Luminaires, like that shown in Figure 516.4(C)(3) , that are an integral part of the walls or ceilingof a spray area shall be permitted to be separated from the spray area by glass panels that are anintegral part of the fixture. Such fixtures shall be listed for use in Class I, Division 2; Class I, Zone2; Class II, Division 2; or Zone 22 locations, whichever is applicable, and also shall be listed foraccumulations of deposits of combustible residues. Such fixtures shall be permitted to be servicedfrom inside the spray area. [ 33: 6.6.3]

(0) Glass panels used to separate luminaires from the spray area or that are an integral part of theluminaire shall meet the following requirements.

0. Panels for light fixtures or for observation shall be of heat-treated glass, laminated glass,wired glass, or hammered-wired glass and shall be sealed to confine vapors, mists,residues, dusts, and deposits to the spray area. [ 33: 5.5.1]

Exception: Listed spray booth assemblies that have vision panels constructed of othermaterials shall be permitted.

0. Panels for light fixtures shall be separated from the fixture to prevent the surfacetemperature of the panel from exceeding 93°C (200°F). [ 33: 5.5.2]

0. The panel frame and method of attachment shall be designed to not fail under fire exposurebefore the vision panel fails. [ 33: 5.5.3]

Figure 516.4(C)(1) Example of a Luminaire that is Mounted Outside of the Spray Area and isServiced from Outside the Spray Area. [33:Figure 6.6.1]

Figure 516.4(C)(3) Example of a Luminaire that is an Integral Part of the Spray Area and isServiced from Inside the Spray Area. [33:Figure 6.6.3]


243 of 270 4/16/2015 11:12 AM

(D) Portable Equipment.

Portable electric luminaires or other utilization equipment shall not be used in a spray area during sprayoperations.

Exception No. 1: Where portable electric luminaires are required for operations in spaces not readilyilluminated by fixed lighting within the spraying area, they shall be of the type identified for Class I,Division 1 or Class 1, Zone 1 locations where readily ignitible residues may be present. [ 33: 6.9Exception]

Exception No. 2: Where portable electric drying apparatus is used in spray booths and the followingrequirements are met:

(0) The apparatus and its electrical connections are not located within the spray enclosure duringspray operations.

(0) Electrical equipment within 450 mm (18 in.) of the floor is identified for Class I, Division 2 orClass I, Zone 2 locations.

(0) All metallic parts of the drying apparatus are electrically bonded and grounded.

(0) Interlocks are provided to prevent the operation of spray equipment while drying apparatus iswithin the spray enclosure, to allow for a 3-minute purge of the enclosure before energizing thedrying apparatus and to shut off drying apparatus on failure of ventilation system.

(E) Electrostatic Equipment.

Electrostatic spraying or detearing equipment shall be installed and used only as provided in 516.10 .

Informational Note: For further information, see NFPA 33 -2011, Standard for Spray ApplicationUsing Flammable or Combustible Materials .

(F) Static Electric Discharges.

(0) All persons and all electrically conductive objects, including any metal parts of the processequipment or apparatus, containers of material, exhaust ducts, and piping systems that conveyflammable or combustible liquids, shall be electrically grounded. [ 34: 6.8.1]

(0) Provision shall be made to dissipate static electric charges from all nonconductive substrates inprinting processes.

516.7 Wiring and Equipment Not Within Classified Locations.


244 of 270 4/16/2015 11:12 AM

(A) Wiring.

All fixed wiring above the Class I and II locations shall be in metal raceways, Type PVC conduit, TypeRTRC conduit, or electrical nonmetallic tubing; where cables are used, they shall be Type MI, Type TC,or Type MC cable. Cellular metal floor raceways shall only be permitted to supply ceiling outlets or asextensions to the area below the floor of a Class I or II location. Where cellular metal raceways areused, they shall not have connections leading into or passing through the Class I or II location unlesssuitable seals are provided.

(B) Equipment.

Equipment that may produce arcs, sparks, or particles of hot metal, such as lamps and lampholders forfixed lighting, cutouts, switches, receptacles, motors, or other equipment having make-and-break orsliding contacts, where installed above a classified location or above a location where freshly finishedgoods are handled, shall be of the totally enclosed type or be constructed so as to prevent the escape ofsparks or hot metal particles.

516.10 Special Equipment.

(A) Fixed Electrostatic Equipment.

This section shall apply to any equipment using electrostatically charged elements for the atomization,charging, and/or precipitation of hazardous materials for coatings on articles or for other similarpurposes in which the charging or atomizing device is attached to a mechanical support or manipulator.This shall include robotic devices. This section shall not apply to devices that are held or manipulated byhand. Where robot or programming procedures involve manual manipulation of the robot arm whilespraying with the high voltage on, the provisions of 516.10(B) shall apply. The installation ofelectrostatic spraying equipment shall comply with 516.10(A)(1) through (A)(10). Spray equipmentshall be listed except as otherwise permitted. All automatic electrostatic equipment systems shallcomply with 516.4(A) (1) through (A)(9). [ 33: 11.5]

Informational Note: For more information on listing and approval of electrostatic sprayequipment, see NFPA 33 -2011, Standard for Spray Application Using Flammable orCombustible Materials , Section 11.5. NFPA 33 permits certain electrostatic spray equipment tobe approved for use when additional mitigation equipment is employed.

(1) Power and Control Equipment.

Transformers, high-voltage supplies, control apparatus, and all other electrical portions of the equipmentshall be installed outside of the Class I location as defined in 516.3 or be of a type identified for thelocation.

Exception: High-voltage grids, electrodes, electrostatic atomizing heads, and their connections shallbe permitted within the Class I location.

(2) Electrostatic Equipment.

Electrodes and electrostatic atomizing heads shall be adequately supported in permanent locations andshall be effectively insulated from ground. Electrodes and electrostatic atomizing heads that arepermanently attached to their bases, supports, reciprocators, or robots shall be deemed to comply withthis section.

(3) High-Voltage Leads.

High-voltage leads shall be properly insulated and protected from mechanical damage or exposure todestructive chemicals. Any exposed element at high voltage shall be effectively and permanentlysupported on suitable insulators and shall be effectively guarded against accidental contact orgrounding.

(4) Support of Goods.

Goods being coated using this process shall be supported on conveyors or hangers. The conveyors orhangers shall be arranged (1) to ensure that the parts being coated are electrically connected to groundwith a resistance of 1 megohm or less and (2) to prevent parts from swinging.


245 of 270 4/16/2015 11:12 AM

(5) Automatic Controls.

Electrostatic apparatus shall be equipped with automatic means that will rapidly de-energize thehigh-voltage elements under any of the following conditions:

(0) Stoppage of ventilating fans or failure of ventilating equipment from any cause

(0) Stoppage of the conveyor carrying goods through the high-voltage field unless stoppage isrequired by the spray process

(0) Occurrence of excessive current leakage at any point in the high-voltage system

(0) De-energizing the primary voltage input to the power supply

(6) Grounding.

All electrically conductive objects in the spray area, except those objects required by the process to beat high voltage, shall be adequately grounded. This requirement shall apply to paint containers, washcans, guards, hose connectors, brackets, and any other electrically conductive objects or devices in thearea.

Informational Note: For more information on grounding and bonding for static electricitypurposes, see NFPA 33 -2011, Standard for Spray Application Using Flammable orCombustible Materials ; NFPA 34 -2011, Standard for Dipping, Coating, and Printing ProcessesUsing Flammable or Combustible Liquids ; and NFPA 77 -2014, Recommended Practice onStatic Electricity .

(7) Isolation.

Safeguards such as adequate booths, fencing, railings, interlocks, or other means shall be placed aboutthe equipment or incorporated therein so that they, either by their location, character, or both, ensurethat a safe separation of the process is maintained.

(8) Signs.

Signs shall be conspicuously posted to convey the following:

(0) Designate the process zone as dangerous with regard to fire and accident

(0) Identify the grounding requirements for all electrically conductive objects in the spray area

(0) Restrict access to qualified personnel only

(9) Insulators.

All insulators shall be kept clean and dry.

(10) Other Than Nonincendive Equipment.

Spray equipment that cannot be classified as nonincendive shall comply with (A)(10)(a) and (A)(10)(b).

(0) Conveyors, hangers, and application equipment shall be arranged so that a minimum separationof at least twice the sparking distance is maintained between the workpiece or material beingsprayed and electrodes, electrostatic atomizing heads, or charged conductors. Warnings definingthis safe distance shall be posted. [ 33: 11.4.1]

(0) The equipment shall provide an automatic means of rapidly de-energizing the high-voltageelements in the event the distance between the goods being painted and the electrodes orelectrostatic atomizing heads falls below that specified in (a). [ 33: 11.3.8]

(B) Electrostatic Hand-Spraying Equipment.

This section shall apply to any equipment using electrostatically charged elements for the atomization,charging, or precipitation of flammable and combustible materials for coatings on articles, or for othersimilar purposes in which the charging or atomizing device is hand-held and manipulated during thespraying operation. Electrostatic hand-spraying equipment and devices used in connection with paint-spraying operations shall be of listed types and shall comply with 516.10(B)(1) through (B)(5).


246 of 270 4/16/2015 11:12 AM

(1) General.

The high-voltage circuits shall be designed so as not to produce a spark of sufficient intensity to ignitethe most readily ignitible of those vapor–air mixtures likely to be encountered, or result in appreciableshock hazard upon coming in contact with a grounded object under all normal operating conditions. Theelectrostatically charged exposed elements of the handgun shall be capable of being energized only byan actuator that also controls the coating material supply.

(2) Power Equipment.

Transformers, power packs, control apparatus, and all other electrical portions of the equipment shall belocated outside of the Class I location or be identified for the location.

Exception: The handgun itself and its connections to the power supply shall be permitted within theClass I location.

(3) Handle.

The handle of the spraying gun shall be electrically connected to ground by a conductive material andbe constructed so that the operator in normal operating position is in direct electrical contact with thegrounded handle with a resistance of not more than 1 megohm to prevent buildup of a static charge onthe operator’s body. Signs indicating the necessity for grounding other persons entering the spray areashall be conspicuously posted.


All electrically conductive objects in the spraying area, except those objects required by the process tobe at high voltage, shall be electrically connected to ground with a resistance of not more than 1megohm. This requirement shall apply to paint containers, wash cans, and any other electricalconductive objects or devices in the area. The equipment shall carry a prominent, permanently installedwarning regarding the necessity for this grounding feature.

Informational Note: For more information on grounding and bonding for static electricitypurposes, see NFPA 33 -2011, Standard for Spray Application Using Flammable orCombustible Materials ; NFPA 34 -2011, Standard for Dipping, Coating, and Printing ProcessesUsing Flammable or Combustible Liquids ; and NFPA 77 -2014, Recommended Practice onStatic Electricity .

(5) Support of Objects.

Objects being painted shall be maintained in electrical contact with the conveyor or other groundedsupport. Hooks shall be regularly cleaned to ensure adequate grounding of 1 megohm or less. Areas ofcontact shall be sharp points or knife edges where possible. Points of support of the object shall beconcealed from random spray where feasible; and, where the objects being sprayed are supported froma conveyor, the point of attachment to the conveyor shall be located so as to not collect spray materialduring normal operation. [ 33: Chapter 12]

(C) Powder Coating.

This section shall apply to processes in which combustible dry powders are applied. The hazardsassociated with combustible dusts are present in such a process to a degree, depending on thechemical composition of the material, particle size, shape, and distribution.

(1) Electrical Equipment and Sources of Ignition.

Electrical equipment and other sources of ignition shall comply with the requirements of Article 502 .Portable electric luminaires and other utilization equipment shall not be used within a Class II locationduring operation of the finishing processes. Where such luminaires or utilization equipment are usedduring cleaning or repairing operations, they shall be of a type identified for Class II, Division 1 locations,and all exposed metal parts shall be connected to an equipment grounding conductor.

Exception: Where portable electric luminaires are required for operations in spaces not readilyilluminated by fixed lighting within the spraying area, they shall be of the type listed for Class II,Division 1 locations where readily ignitible residues may be present.

(2) Fixed Electrostatic Spraying Equipment.

The provisions of 516.10(A) and 516.10(C)(1) shall apply to fixed electrostatic spraying equipment.

(3) Electrostatic Hand-Spraying Equipment.

The provisions of 516.10(B) and 516.10(C)(1) shall apply to electrostatic hand-spraying equipment.


247 of 270 4/16/2015 11:12 AM

(4) Electrostatic Fluidized Beds.

Electrostatic fluidized beds and associated equipment shall be of identified types. The high-voltagecircuits shall be designed such that any discharge produced when the charging electrodes of the bedare approached or contacted by a grounded object shall not be of sufficient intensity to ignite anypowder–air mixture likely to be encountered or to result in an appreciable shock hazard.

(0) Transformers, power packs, control apparatus, and all other electrical portions of the equipmentshall be located outside the powder-coating area or shall otherwise comply with the requirementsof 516.10(C)(1) .

Exception: The charging electrodes and their connections to the power supply shall bepermitted within the powder-coating area.

(0) All electrically conductive objects within the powder-coating area shall be adequately grounded.The powder-coating equipment shall carry a prominent, permanently installed warning regardingthe necessity for grounding these objects.

Informational Note: For more information on grounding and bonding for static electricitypurposes, see NFPA 33 -2011, Standard for Spray Application Using Flammable orCombustible Materials ; NFPA 34 -2011, Standard for Dipping, Coating, and PrintingProcesses Using Flammable or Combustible Liquids ; and NFPA 77 -2014,Recommended Practice on Static Electricity .

(0) Objects being coated shall be maintained in electrical contact (less than 1 megohm) with theconveyor or other support in order to ensure proper grounding. Hangers shall be regularly cleanedto ensure effective electrical contact. Areas of electrical contact shall be sharp points or knifeedges where possible.

(0) The electrical equipment and compressed air supplies shall be interlocked with a ventilationsystem so that the equipment cannot be operated unless the ventilating fans are in operation.[ 33: Chapter 15]

516.16 Grounding.

All metal raceways, the metal armors or metallic sheath on cables, and all non–current-carrying metalparts of fixed or portable electrical equipment, regardless of voltage, shall be grounded and bonded.Grounding and bonding shall comply with 501.30 , 502.30 , or 505.25 , as applicable.

Part II. Open Containers


248 of 270 4/16/2015 11:12 AM

516.4 Area Classification.

For open containers, supply containers, waste containers, spray gun cleaners, and solvent distillationunits that contain Class I liquids that are located in ventilated areas, electrical area classification shall bein accordance with the following:

(1) The area within 915 mm (3 ft) in all directions from any such container or equipment andextending to the floor or grade level shall be classified as Class I, Division 1 or Class I, Zone 1,whichever is applicable. [ 33: 6.5.5.1]

(2) The area extending 610 mm (2 ft) beyond the Division 1 or Zone 1 location shall be classified asClass I, Division 2 or Class I, Zone 2, whichever is applicable. [ 33: 6.5.5.1]

(3) The area extending 1525 mm (5 ft) horizontally beyond the area described in 516.4 (b) up to aheight of 460 mm (18 in.) above the floor or grade level shall be classified as Class I, Division 2 orClass I, Zone 2, whichever is applicable. [ 33: 6.5.5.1]

(4) The area inside any tank or container shall be classified as Class I, Division 1 or Class I, Zone 0,whichever is applicable. [ 33: 6.5.5.1]

(5) Sumps, pits, or below grade channels within 3.5 m (10 ft) horizontally of a vapor source shall beclassified as Class I, Division 1 or Zone 1. If the sump, pit, or channel extends beyond 3.5 m (10ft) from the vapor source, it shall be provided with a vapor stop or it shall be classified as Class I,Division 1 or Zone 1 for its entire length.

For the purposes of electrical area classification, the Division system and the Zone system shall not beintermixed for any given source of release. [ 33: 6.2.3]

Electrical wiring and utilization equipment installed in these areas shall be suitable for the location, asshown in Figure 516.4 . [ 33: 6.5.5.2]

Figure 516.4 Electrical Area Classification for Class I Liquid Operations Around OpenContainers, Supply Containers, Waste Containers, Spray Gun Cleaners, and SolventDistillation Units. [ 33: Figure 6.5.5.2]

Part III. Spray Application Processes

516.5 Area Classification.

For spray application processes, the area classification is based on quantities of flammable vapors,combustible mists, residues, dusts, or deposits that are present or might be present in quantitiessufficient to produce ignitable or explosive mixtures with air.

(A) Zone Classification of Locations.


249 of 270 4/16/2015 11:12 AM

(1) Classification of Locations.

The Zone system of electrical area classification shall be applied as follows:

(1) The inside of closed containers or vessels shall be considered a Class I, Zone 0 location.

(2) A Class I, Division 1 location shall be permitted to be alternatively classified as a Class I, Zone 1location.

(3) A Class I, Division 2 location shall be permitted to be alternatively classified as a Class I, Zone 2location.

(4) A Class II, Division 1 location shall be permitted to be alternatively classified as a Zone 21location.

(5) A Class II, Division 2 location shall be permitted to be alternatively classified as a Zone 22location. [ 33: 6.2.2]

(2)

For the purposes of electrical area classification, the Division system and the Zone system shall not beintermixed for any given source of release. [ 33: 6.2.3]

(3)

In instances of areas within the same facility classified separately, Class I, Zone 2 locations shall bepermitted to abut, but not overlap, Class I, Division 2 locations. Class I, Zone 0 or Zone 1 locations shallnot abut Class I, Division 1 or Division 2 locations. [ 70: 505.7(B)] [ 33: 6.2.4]

(4)

Open flames, spark-producing equipment or processes, and equipment whose exposed surfacesexceed the autoignition temperature of the material being sprayed shall not be located in a spray area orin any surrounding area that is classified as Division 2, Zone 2, or Zone 22. [ 33: 6.2.5]

Exception: This requirement shall not apply to drying, curing, or fusing apparatus.

(5)

Any utilization equipment or apparatus that is capable of producing sparks or particles of hot metal andthat is located above or adjacent to either the spray area or the surrounding Division 2, Zone 2, or Zone22 areas shall be of the totally enclosed type or shall be constructed to prevent the escape of sparks orparticles of hot metal. [ 33: 6.2.6]

(B) Class I, Division 1 or Class I, Zone 0 Locations.

The interior of any open or closed container or vessel of a flammable liquid shall be considered Class I,Division 1, or Class I, Zone 0, as applicable:

Informational Note: For additional guidance, see Chapter 6 of NFPA 33 -2015, Standard forSpray Application Using Flammable or Combustible Materials .

(C) Class I, Division 1; Class I, Zone 1; Class II, Division 1; or Zone 21 Locations.

The following spaces shall be considered Class I, Division 1; Class I, Zone 1; Class II, Division 1; orZone 21 locations, as applicable:

(1) The interior of spray booths and rooms except as specifically provided in 516.5(D) .

(2) The interior of exhaust ducts.

(3) Any area in the direct path of spray operations.

(4) Sumps, pits, or below grade channels within 7.5 m (25 ft) horizontally of a vapor source. If thesump, pit, or channel extends beyond 7.5 m (25 ft) from the vapor source, it shall be provided witha vapor stop or it shall be classified as Class I, Division 1 for its entire length. [ 34: 6.4.1]

(5) All space in all directions outside of but within 900 mm (3 ft) of open containers, supplycontainers, spray gun cleaners, and solvent distillation units containing flammable liquids.

(6) For limited finishing workstations, the area inside the curtains or partitions. [See Figure516.5(D)(5) .]

(D) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 Locations.

The spaces listed in 516.5(D)(1) through (D)(5) shall be considered Class I, Division 2; Class I, Zone2; Class II, Division 2; or Zone 22 as applicable.


250 of 270 4/16/2015 11:12 AM

(1) Unenclosed Spray Processes.

For unenclosed spraying, all space outside of but within 6 m (20 ft) horizontally and 3 m (10 ft) verticallyof the Class I, Division 1 or Class I, Zone 1 location as defined in 516.5(A) and not separated from itby partitions. [See Figure 516.5(D)(1) .] [ 33: 6.5.1]

Figure 516.5(D)(1) Electrical Area Classification for Unenclosed Spray Areas. [33:Figure 6.5.1]

(2) Closed-Top, Open-Face, and Open-Front Spray Booths and Spray Rooms.

If spray application operations are conducted within a closed-top, open-face, or open-front booth orroom, as shown in Figure 516.5(D)(2) , any electrical wiring or utilization equipment located outside ofthe booth or room but within 915 mm (3 ft) of any opening shall be suitable for Class I, Division 2; ClassI, Zone 2; Class II, Division 2; or Zone 22 locations, whichever is applicable. The Class I, Division 2;Class I, Zone 2; Class II, Division 2; or Zone 22 locations shown in Figure 516.5(D)(2) shall extendfrom the edges of the open face or open front of the booth or room.

Figure 516.5(D)(2) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 LocationsAdjacent to a Closed Top, Open Face, or Open Front Spray Booth or Room. [33:Figure 6.5.2]

(3) Open-Top Spray Booths.

For spraying operations conducted within an open top spray booth, the space 915 mm (3 ft) verticallyabove the booth and within 915 mm (3 ft) of other booth openings shall be considered Class I, Division2; Class I, Zone 2; Class II, Division 2; or Zone 22 whichever is applicable. [ 33: 6.5.3]


251 of 270 4/16/2015 11:12 AM

(4) Enclosed Spray Booths and Spray Rooms.

For spray application operations confined to an enclosed spray booth or room, electrical areaclassification shall be as follows: [ 33: 6.5.4]

(1) The area within 915 mm (3 ft) of any opening shall be classified as Class I, Division 2; Class I,Zone 2; Class II, Division 2; or Zone 22 locations, whichever is applicable, as shown in Figure516.5(D)(4) .

(2) Where automated spray application equipment is used, the area outside the access doors shallbe unclassified provided the door interlock prevents the spray application operations when thedoor is open.

(3) Where exhaust air is permitted to be recirculated, both of the following shall apply:

a. The interior of any recirculation path from the secondary particulate filters up to andincluding the air supply plenum shall be classified as Class I, Division 2; Class I, Zone 2;Class II, Division 2; or Zone 22 locations, whichever is applicable.

b. The interior of fresh air supply ducts shall be unclassified. [ 33: 6.5.4]

(4) Where exhaust air is not recirculated, the interior of fresh air supply ducts and fresh air supplyplenums shall be unclassified. [ 33: 6.5.4]


252 of 270 4/16/2015 11:12 AM

(5) Limited Finishing Workstations.

For limited finishing workstations, the area inside the 915 mm (3 ft) space horizontally and verticallybeyond the volume enclosed by the outside surface of the curtains or partitions shall be classified asClass I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22, as shown in Figure 516.5(D)(5) .

Figure 516.5(D)(4) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 LocationsAdjacent to an Enclosed Spray Booth or Spray Room. [33:Figure 6.5.4]

Figure 516.5(D)(5) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 LocationsAdjacent to an Enclosed Spray Booth or Spray Room. [33:Figure 14.3.5.1]

516.6 Wiring and Equipment in Class I Locations.

(A) Wiring and Equipment — Vapors.

All electrical wiring and equipment within the Class I location (containing vapor only — not residues)defined in 516.5 shall comply with the applicable provisions of Article 501 or Article 505 , asapplicable.


253 of 270 4/16/2015 11:12 AM

(B) Wiring and Equipment — Vapors and Residues.

Unless specifically listed for locations containing deposits of dangerous quantities of flammable orcombustible vapors, mists, residues, dusts, or deposits (as applicable), there shall be no electricalequipment in any spray area as herein defined whereon deposits of combustible residue may readilyaccumulate, except wiring in rigid metal conduit, intermediate metal conduit, Type MI cable, or in metalboxes or fittings containing no taps, splices, or terminal connections. [ 33: 6.4.2]


254 of 270 4/16/2015 11:12 AM

(C) Illumination.


255 of 270 4/16/2015 11:12 AM

Luminaires shall be permitted to be installed as follows:

(1) Luminaires, like that shown in Figure 516.6(C)(a) , that are attached to the walls or ceiling of aspray area but that are outside any classified area and are separated from the spray area byglass panels shall be suitable for use in unclassified locations. Such fixtures shall be servicedfrom outside the spray area. [ 33: 6.6.1]

(2) Luminaires, like that shown in Figure 516.6(C)(a) , that are attached to the walls or ceiling of aspray area; that are separated from the spray area by glass panels and that are located within aClass I, Division 2; a Class I, Zone 2; a Class II, Division 2; or a Zone 22 location shall be suitablefor such location. Such fixtures shall be serviced from outside the spray area. [ 33: 6.6.2]

(3) Luminaires, like that shown in Figure 516.6(C)(b) , that are an integral part of the walls or ceilingof a spray area shall be permitted to be separated from the spray area by glass panels that are anintegral part of the fixture. Such fixtures shall be listed for use in Class I, Division 2; Class I, Zone2; Class II, Division 2; or Zone 22 locations, whichever is applicable, and also shall be listed foraccumulations of deposits of combustible residues. Such fixtures shall be permitted to be servicedfrom inside the spray area. [ 33: 6.6.3]

(4) Glass panels used to separate luminaires from the spray area or that are an integral part of theluminaire shall meet the following requirements.

a. Panels for light fixtures or for observation shall be of heat-treated glass, laminated glass,wired glass, or hammered-wired glass and shall be sealed to confine vapors, mists,residues, dusts, and deposits to the spray area. [ 33: 5.5.1]

Exception: Listed spray booth assemblies that have vision panels constructed of othermaterials shall be permitted.

b. Panels for light fixtures shall be separated from the fixture to prevent the surfacetemperature of the panel from exceeding 93°C (200°F). [ 33: 5.5.2]

c. The panel frame and method of attachment shall be designed to not fail under fire exposurebefore the vision panel fails. [ 33: 5.5.3]

Figure 516.6(C)(a) Example of a Luminaire that is Mounted Outside of the Spray Area and isServiced from Outside the Spray Area. [33:Figure 6.6.1]

Figure 516.6(C)(b) Example of a Luminaire that is an Integral Part of the Spray Area and isServiced from Inside the Spray Area. [33:Figure 6.6.3]


256 of 270 4/16/2015 11:12 AM

(D) Portable Equipment.

Portable electric luminaires or other utilization equipment shall not be used in a spray area during sprayoperations.

Exception No. 1: Where portable electric luminaires are required for operations in spaces not readilyilluminated by fixed lighting within the spraying area, they shall be of the type identified for Class I,Division 1 or Class 1, Zone 1 locations where readily ignitible residues may be present. [ 33: 6.9Exception]

Exception No. 2: Where portable electric drying apparatus is used in spray booths and the followingrequirements are met:

(a) The apparatus and its electrical connections are not located within the spray enclosure duringspray operations.

(b) Electrical equipment within 450 mm (18 in.) of the floor is identified for Class I, Division 2 orClass I, Zone 2 locations.

(c) All metallic parts of the drying apparatus are electrically bonded and grounded.

(d) Interlocks are provided to prevent the operation of spray equipment while drying apparatus iswithin the spray enclosure, to allow for a 3-minute purge of the enclosure before energizing thedrying apparatus and to shut off drying apparatus on failure of ventilation system.

(E) Electrostatic Equipment.

Electrostatic spraying or detearing equipment shall be installed and used only as provided in 516.10.

Informational Note: For further information, see NFPA 33 -2015, Standard for Spray ApplicationUsing Flammable or Combustible Materials .

(F) Static Electric Discharges.

All persons and all electrically conductive objects, including any metal parts of the process equipment orapparatus, containers of material, exhaust ducts, and piping systems that convey flammable orcombustible liquids, shall be electrically grounded. [ 34: 6.8.1]



257 of 270 4/16/2015 11:12 AM

(A) Wiring.

All fixed wiring above the Class I and II locations shall be in metal raceways, Type PVC conduit, TypeRTRC conduit, or electrical nonmetallic tubing; where cables are used, they shall be Type MI, Type TC,or Type MC cable. Cellular metal floor raceways shall only be permitted to supply ceiling outlets or asextensions to the area below the floor of a Class I or II location. Where cellular metal raceways, areused, they shall not have connections leading into or passing through the Class I or II location unlesssuitable seals are provided.

(B) Equipment.

Equipment that may produce arcs, sparks, or particles of hot metal, such as lamps and lampholders forfixed lighting, cutouts, switches, receptacles, motors, or other equipment having make-and-break orsliding contacts, where installed above a classified location or above a location where freshly finishedgoods are handled, shall be of the totally enclosed type or be constructed so as to prevent the escape ofsparks or hot metal particles.

516.10 Special Equipment.

(A) Fixed Electrostatic Equipment.

This section shall apply to any equipment using electrostatically charged elements for the atomization,charging, and/or precipitation of hazardous materials for coatings on articles or for other similarpurposes in which the charging or atomizing device is attached to a mechanical support or manipulator.This shall include robotic devices. This section shall not apply to devices that are held or manipulated byhand. Where robot or programming procedures involve manual manipulation of the robot arm whilespraying with the high voltage on, the provisions of 516.10(B) shall apply. The installation ofelectrostatic spraying equipment shall comply with 516.10(A)(1) through (A)(10). Spray equipmentshall be listed. All automatic electrostatic equipment systems shall comply with 516.6(A) through (E).

(1) Power and Control Equipment.

Transformers, high-voltage supplies, control apparatus, and all other electrical portions of the equipmentshall be installed outside of the Class I location or be of a type identified for the location.

Exception: High-voltage grids, electrodes, electrostatic atomizing heads, and their connections shallbe permitted within the Class I location.


Electrodes and electrostatic atomizing heads shall be adequately supported in permanent locations andshall be effectively insulated from ground. Electrodes and electrostatic atomizing heads that arepermanently attached to their bases, supports, reciprocators, or robots shall be deemed to comply withthis section.

(3) High-Voltage Leads.

High-voltage leads shall be properly insulated and protected from mechanical damage or exposure todestructive chemicals. Any exposed element at high voltage shall be effectively and permanentlysupported on suitable insulators and shall be effectively guarded against accidental contact orgrounding.

(4) Support of Goods.

Goods being coated using this process shall be supported on conveyors or hangers. The conveyors orhangers shall be arranged (1) to ensure that the parts being coated are electrically connected to groundwith a resistance of 1 megohm or less and (2) to prevent parts from swinging.

(5) Automatic Controls.

Electrostatic apparatus shall be equipped with automatic means that will rapidly de-energize thehigh-voltage elements under any of the following conditions:

(1) Stoppage of ventilating fans or failure of ventilating equipment from any cause

(2) Stoppage of the conveyor carrying goods through the high-voltage field unless stoppage isrequired by the spray process

(3) Occurrence of excessive current leakage at any point in the high-voltage system

(4) De-energizing the primary voltage input to the power supply


258 of 270 4/16/2015 11:12 AM

(6) Grounding.

All electrically conductive objects in the spray area, except those objects required by the process to beat high voltage, shall be adequately grounded. This requirement shall apply to paint containers, washcans, guards, hose connectors, brackets, and any other electrically conductive objects or devices in thearea.

Informational Note: For more information on grounding and bonding for static electricitypurposes, see NFPA 33 -2015, Standard for Spray Application Using Flammable orCombustible Materials ; NFPA 34 -2015, Standard for Dipping, Coating, and PrintingProcesses Using Flammable or Combustible Liquids ; and NFPA 77 -2007, RecommendedPractice on Static Electricity .

(7) Isolation.

Safeguards such as adequate booths, fencing, railings, interlocks, or other means shall be placed aboutthe equipment or incorporated therein so that they, either by their location, character, or both, ensurethat a safe separation of the process is maintained.

(8) Signs.

Signs shall be conspicuously posted to convey the following:

(1) Designate the process zone as dangerous with regard to fire and accident

(2) Identify the grounding requirements for all electrically conductive objects in the spray area

(3) Restrict access to qualified personnel only

(9) Insulators.

All insulators shall be kept clean and dry.

(10) Other Than Nonincendive Equipment.

Spray equipment that cannot be classified as nonincendive shall comply with (A)(10)(a) and (A)(10)(b).

(a) Conveyors, hangers, and application equipment shall be arranged so that a minimum separationof at least twice the sparking distance is maintained between the workpiece or material beingsprayed and electrodes, electrostatic atomizing heads, or charged conductors. Warnings definingthis safe distance shall be posted. [ 33: 11.4.1]

(b) The equipment shall provide an automatic means of rapidly de-energizing the high-voltageelements in the event the distance between the goods being painted and the electrodes orelectrostatic atomizing heads falls below that specified in (a). [ 33: 11.3.8]

(B) Hand-Spraying Electrostatic Equipment.

This section shall apply to any equipment using electrostatically charged elements for the atomization,charging, or precipitation of flammable and combustible materials for coatings on articles, or for othersimilar purposes in which the charging or atomizing device is hand-held and manipulated during thespraying operation. Electrostatic hand-spraying equipment and devices used in connection with paint-spraying operations shall be of listed types and shall comply with 516.10(B)(1) through (B)(5).

(1) General.

The high-voltage circuits shall be designed so as not to produce a spark of sufficient intensity to ignitethe most readily ignitible of those vapor–air mixtures likely to be encountered, or result in appreciableshock hazard upon coming in contact with a grounded object under all normal operating conditions. Theelectrostatically charged exposed elements of the handgun shall be capable of being energized only byan actuator that also controls the coating material supply.

(2) Power Equipment.

Transformers, power packs, control apparatus, and all other electrical portions of the equipment shall belocated outside of the Class I location or be identified for the location.

Exception: The handgun itself and its connections to the power supply shall be permitted within theClass I location.


259 of 270 4/16/2015 11:12 AM

(3) Handle.

The handle of the spraying gun shall be electrically connected to ground by a conductive material andbe constructed so that the operator in normal operating position is in electrical contact with the groundedhandle with a resistance of not more than 1 megohm to prevent buildup of a static charge on theoperator’s body. Signs indicating the necessity for grounding other persons entering the spray area shallbe conspicuously posted.


All electrically conductive objects in the spraying area, except those objects required by the process tobe at high voltage shall be electrically connected to ground with a resistance of not more than 1megohm. This requirement shall apply to paint containers, wash cans, and any other electricalconductive objects or devices in the area. The equipment shall carry a prominent, permanently installedwarning regarding the necessity for this grounding feature.

Informational Note: For more information on grounding and bonding for static electricitypurposes, see NFPA 33 -2015, Standard for Spray Application Using Flammable orCombustible Materials ; NFPA 34 -2015, Standard for Dipping, Coating, and PrintingProcesses Using Flammable or Combustible Liquids ; and NFPA 77 -2007, RecommendedPractice on Static Electricity .

(5) Support of Objects.

Objects being painted shall be maintained in electrical contact with the conveyor or other groundedsupport. Hooks shall be regularly cleaned to ensure adequate grounding of 1 megohm or less. Areas ofcontact shall be sharp points or knife edges where possible. Points of support of the object shall beconcealed from random spray where feasible; and, where the objects being sprayed are supported froma conveyor, the point of attachment to the conveyor shall be located so as to not collect spray materialduring normal operation.

(C) Powder Coating.

This section shall apply to processes in which combustible dry powders are applied. The hazardsassociated with combustible dusts are present in such a process to a degree, depending on thechemical composition of the material, particle size, shape, and distribution.

(1) Electrical Equipment and Sources of Ignition.

Electrical equipment and other sources of ignition shall comply with the requirements of Article 502 .Portable electric luminaires and other utilization equipment shall not be used within a Class II locationduring operation of the finishing processes. Where such luminaires or utilization equipment are usedduring cleaning or repairing operations, they shall be of a type identified for Class II, Division 1 locations,and all exposed metal parts shall be connected to an equipment grounding conductor.

Exception: Where portable electric luminaires are required for operations in spaces not readilyilluminated by fixed lighting within the spraying area, they shall be of the type listed for Class II,Division 1 locations where readily ignitible residues may be present.

(2) Fixed Electrostatic Spraying Equipment.

The provisions of 516.10(A) and 516.10(C)(1) shall apply to fixed electrostatic spraying equipment.

(3) Electrostatic Hand-Spraying Equipment.

The provisions of 516.10(B) and 516.10(C)(1) shall apply to electrostatic hand-spraying equipment.


260 of 270 4/16/2015 11:12 AM

(4) Electrostatic Fluidized Beds.

Electrostatic fluidized beds and associated equipment shall be of identified types. The high-voltagecircuits shall be designed such that any discharge produced when the charging electrodes of the bedare approached or contacted by a grounded object shall not be of sufficient intensity to ignite anypowder–air mixture likely to be encountered or to result in an appreciable shock hazard.

(a) Transformers, power packs, control apparatus, and all other electrical portions of the equipmentshall be located outside the powder-coating area or shall otherwise comply with the requirementsof 516.10(C)(1) .

Exception: The charging electrodes and their connections to the power supply shall bepermitted within the powder-coating area.

(b) All electrically conductive objects within the powder-coating area shall be adequately grounded.The powder-coating equipment shall carry a prominent, permanently installed warning regardingthe necessity for grounding these objects.

Informational Note: For more information on grounding and bonding for static electricitypurposes, see NFPA 33 -2015, Standard for Spray Application Using Flammable orCombustible Materials ; NFPA 34 -2015, Standard for Dipping, Coating, and PrintingProcesses Using Flammable or Combustible Liquids ; and NFPA 77 -2007,Recommended Practice on Static Electricity .

(c) Objects being coated shall be maintained in electrical contact (less than 1 megohm) with theconveyor or other support in order to ensure proper grounding. Hangers shall be regularly cleanedto ensure effective electrical contact. Areas of electrical contact shall be sharp points or knifeedges where possible.

(d) The electrical equipment and compressed air supplies shall be interlocked with a ventilationsystem so that the equipment cannot be operated unless the ventilating fans are in operation.[ 33: Chapter 15]

516.16 Grounding.

All metal raceways, the metal armors or metallic sheath on cables, and all non–current-carrying metalparts of fixed or portable electrical equipment, regardless of voltage, shall be grounded and bonded.Grounding and bonding shall comply with 501.30 , 502.30 , or 505.25 , as applicable.

Part IV. Spray Application Operations in Membrane Enclosures

516.18 Membrane Enclosure Use.

Spray application operations within both outdoor and indoor temporary membrane enclosures shall belimited to workpieces that cannot be moved into a spray booth and where open spraying is not practicaldue to the proximity to other operations, finish quality, or concerns such as the collection of overspray.

(1) Spray application operations and processes within the enclosure shall only be permitted for theworkpiece for which the enclosure was erected.

(2) Spray application operations for parts removed from the workpiece shall be conducted inaccordance with applicable requirements of this standard.

(3) Membrane enclosures shall be erected for 180 days or less.

(4) Enclosures erected under this chapter shall only be used for the duration of a spray operation at afixed location which can involve multiple coats for a single workpiece.

(5) Membrane material shall not be reused for any other spray application operations.

(6) Operations conducted within the enclosure other than spray applications shall meet the fire andsafety requirements for those operations.

(7) These operations shall not take place while the spray application operation is in progress.

Informational Note: For additional guidance, see Chapter 18 of NFPA 33 -2015, Standard forSpray Application Using Flammable or Combustible Materials .

516.20 Location of Temporary Membrane Enclosures.

Temporary membrane enclosures shall be permitted to be located in accordance with 516.20(A) and516.20(B) .


261 of 270 4/16/2015 11:12 AM

(A) Outside of Buildings.

The spray area shall be separated from permanent structures by a minimum of 4.6 m (15 ft).

(B) Inside of Buildings.

Membrane enclosures for spray painting shall be permitted to be installed in buildings provided all of therequirements 516.21 are met.

516.21 Membrane Material.

Membrane materials shall comply with the following requirements:

(1) Material used in a vertical plane for membrane enclosures shall have been tested and passed theNFPA 701 -2010, Standard Methods of Fire Tests for Flame Propagation of Textiles and Films ,Test 2 requirements.

(2) Other than material in a vertical plane, the membrane material shall be listed for installationbeneath sprinklers and in installed to meet the requirements of 8.15.15 of NFPA 13 -2014,Standard for the Installation of Sprinkler Systems .

(3) Where a listed membrane material is used, it shall be considered a drop-out ceiling in NFPA13 -2014, Standard for the Installation of Sprinkler Systems , and follow the applicablerequirements for those assemblies.

Informational Note: Buildings in which membrane enclosures are installed are provided withautomatic sprinkler systems in accordance with the requirements for indoor membraneenclosures of NFPA 33 -2015, Standard for Spray Application Using Flammable or CombustibleMaterials .

516.22 Area Classification for Temporary Membrane Enclosures.

The area classification shall be as given in 516.22(A)(1) through (A)(8) and is illustrated by Figure516.22 .


262 of 270 4/16/2015 11:12 AM

(A) Classification of Locations.

The zone system of electrical area classification shall be applied as follows:

(1) A 1.5 m (5 ft) zone outside of the membrane enclosure shall be considered Class I, Division 2, asshown in Figure 516.22 .

(2) All lighting, electrical power cords, and any related equipment within the membrane enclosureshall be rated for Class I Division 1 as defined by NFPA 70 when used during spray paintoperations.

(3) All lighting, electrical power cords, and any related equipment within the 1.5 m (5 ft) distancehorizontally from the exterior of the membrane enclosure shall be listed for Class I Division 2 asdefined by NFPA 70 when used during spray paint operations.

(4) All power to the workpiece shall be removed during spray painting

(5) Workpieces shall be grounded.

(6) Scaffolding shall be bonded to the workpiece and grounded to an appropriate grounding rod orother approved method consistent with 6.2.1 referenced requirements.

(7) Spray paint equipment shall be grounded.

(8) Equipment used to monitor the concentration of solvent vapors shall be calibrated for the solventsused. The calibration frequency shall be per the manufacturer’s recommendations.

Figure 516.22 Electrical Classifications for Temporary Outdoor Membrane Enclosures[33:Figure 18.7.1.1]

516.23 Electrical and Other Sources of Ignition.

Electrical wiring and utilization equipment used in membrane enclosures during spray painting shallcomply with 516.5(A)(1) .


263 of 270 4/16/2015 11:12 AM

516.24 Ventilation.

Each membrane enclosure shall be provided with mechanical ventilation consistent with the following:

(1) The ventilation system shall be designed and installed to ensure that the enclosure is maintainedat a pressure that is negative relative to the surrounding environs.

(2) The concentration of the vapors and mists in the exhaust stream of the ventilation system duringspray operations and ambient air drying operations shall not exceed 10 percent of the lowerflammable limit.

(3) All spray operations within the membrane enclosure shall cease operations when theconcentration of the vapors and mists in the exhaust stream of the ventilation system reaches orexceeds 10 percent of the lower flammable limit.

(4) An interlock shall be provided so that the spray apparatus is automatically stopped if theventilation system fails to maintain the concentration of the vapors and mists in the exhauststream below 10 percent of the lower flammable limit.

(5) Where interlocks cannot be effectively provided for ventilation equipment that uses plant air, largeair storage tanks, or equipment that cannot be instantly shut off, an audible alarm upon loss ofventilation that will alert all spray paint operators shall be permitted with authority havingjurisdiction approval.

(6) Exhaust air shall be taken from one or more points within 300 mm (12 in.) of the floor of theenclosure.

(7) An adequate supply of clean make-up air shall be provided per the requirements of NFPA33 -2015, Standard for Spray Application Using Flammable or Combustible Materials .

(8) The location of both the exhaust and make-up air openings shall be arranged to provide airmovement throughout the enclosure and across all portions of the floor to prevent accumulation offlammable vapors.

Each membrane spray enclosure shall be provided with mechanical ventilation that is capable ofconfining and removing vapors and mists to a safe location and is capable of confining andcontrolling combustible residues, dusts, and deposits. The concentration of the vapors and mistsin the exhaust stream of the ventilation system shall not exceed 25 percent of the lowerflammable limit.

(9) Air exhausted from the membrane enclosure shall not be recirculated.

Air exhausted to the atmosphere from liquid spray operations shall be conducted by ducts directlyto the outside of the building. Exhaust ducts shall follow the most direct route to the point ofdischarge but shall not penetrate a fire wall. The exhaust discharge shall be directed away fromany fresh air intakes. The exhaust duct discharge point shall be at least 1830 mm (6 ft) from anyexterior wall or roof. The exhaust duct shall not discharge in the direction of any combustibleconstruction that is within 7625 mm (25 ft) of the exhaust duct discharge point, nor shall itdischarge in the direction of any unprotected opening in any noncombustible or limited-combustible construction that is within 7625 mm (25 ft) of the exhaust duct discharge point.

516.25 Drying.

Membrane enclosures used for spray application of flammable or combustible materials shall not beused for drying, curing, or fusing operations at elevated temperature.

Freshly sprayed workpieces shall be dried only in spaces that are ventilated to prevent theconcentration of vapors from exceeding 10 percent of the lower flammable limit.

516.26 Facilities Compliance Permitting.

Spray application within temporary membrane enclosures shall be permitted and approved.

Informational Note: Spray application within temporary membrane enclosures can occur onlyafter the requirements of Chapter 18 of NFPA 33 -2015, Standard for Spray Application UsingFlammable or Combustible Materials , are met.

Part V. Printing, Dipping, and Coating Processes


264 of 270 4/16/2015 11:12 AM

516.29 Classification of Locations.


265 of 270 4/16/2015 11:12 AM

Classification is based on quantities of flammable vapors, combustible mists, residues, dusts, ordeposits that are present or might be present in quantities sufficient to produce ignitable or explosivemixtures with air. Electrical wiring and electrical utilization equipment located adjacent to openprocesses shall comply with the requirements as follows. Examples of these requirements are illustratedin Figure 516.29(a) , Figure 516.29(b) , Figure 516.29(c) , and Figure 516.29(d) .

Informational Note: For additional guidance, see Chapter 6 of NFPA 33 -2015, Standard forSpray Application Using Flammable or Combustible Materials , and Chapter 6 of NFPA34 -2015, Standard for Dipping, Coating, and Printing Processes Using Flammable orCombustible Liquids .

(1) Electrical wiring and electrical utilization equipment located in any sump, pit, or below gradechannel that is within 7620 mm (25 ft) horizontally of a vapor source, as defined by this standard,shall be suitable for Class I, Division 1 or Class I, Zone 1 locations. If the sump, pit, or channelextends beyond 7620 mm (25 ft) of the vapor source, it shall be provided with a vapor stop, or itshall be classified as Class I, Division 1 or Class I, Zone 1 for its entire length. [ 34: 6.4.1]

(2) Electrical wiring and electrical utilization equipment located within 1525 mm (5 ft) of a vaporsource shall be suitable for Class I, Division 1 or Class I, Zone 1 locations. The space inside a diptank, ink fountain, ink reservoir, or ink tank shall be classified as Class I, Division 1 or Class I,Zone 0, whichever is applicable.

(3) Electrical wiring and electrical utilization equipment located within 915 mm (3 ft) of the Class I,Division 1 or Class I, Zone 1 location shall be suitable for Class I, Division 2 or Class I, Zone 2locations, whichever is applicable.

(4) The space 915 mm (3 ft) above the floor and extending 6100 mm (20 ft) horizontally in alldirections from the Class I, Division 1 or Class I, Zone 1 location shall be classified as Class I,Division 2 or Class I, Zone 2, and electrical wiring and electrical utilization equipment locatedwithin this space shall be suitable for Class I, Division 2 or Class I, Zone 2 locations, whichever isapplicable.

(5) This space shall be permitted to be nonclassified for purposes of electrical installations if the

surface area of the vapor source does not exceed 0.5 m 2 (5 ft 2 ), the contents of the dip tank,ink fountain, ink reservoir, or ink tank do not exceed 19 L (5 gal), and the vapor concentrationduring operating and shutdown periods does not exceed 25 percent of the lower flammable limit.

Figure 516.29(a) Electrical Area Classification for Open Dipping and Coating ProcessesWithout Vapor Containment or Ventilation. [34:Figure 6.4(a)]

Figure 516.29(b) Electrical Area Classification for Open Dipping and Coating Processes withPeripheral Vapor Containment and Ventilation — Vapors Confined to Process Equipment.[34:Figure 6.4(b)]


266 of 270 4/16/2015 11:12 AM

Figure 516.29(c) Electrical Area Classification for Open Dipping and Coating Processes withPartial Peripheral Vapor Containment and Ventilation — Vapors NOT Confined to ProcessEquipment. [34:Figure 6.4(c)]

Figure 516.29(d) Electrical Area Classification for a Typical Printing Process. [34:Figure 6.4(d)]


267 of 270 4/16/2015 11:12 AM

516.35 Areas Adjacent to Enclosed Dipping and Coating Processes.

Areas adjacent to enclosed dipping and coating processes are illustrated by Figure 516.35 and shallbe classified as follows:

(1) The interior of any enclosed dipping or coating process or apparatus shall be a Class I, Division 1or Class I, Zone 1 location, and electrical wiring and electrical utilization equipment located withinthis space shall be suitable for Class I, Division 1 or Class I, Zone 1 locations, whichever isapplicable. The area inside the dip tank shall be classified as Class I, Division 1 or Class I, Zone0, whichever is applicable.

(2) The space within 915 mm (3 ft) in all directions from any opening in the enclosure and extendingto the floor or grade level shall be classified as Class I, Division 2 or Class I, Zone 2, and electricalwiring and electrical utilization equipment located within this space shall be suitable for Class I,Division 2 locations or Class I, Zone 2 locations, whichever is applicable.

(3) All other spaces adjacent to an enclosed dipping or coating process or apparatus shall beclassified as nonhazardous for purposes of electrical installations.

Figure 516.35 Electrical Area Classification Around Enclosed Dipping and Coating Processes.[34:Figure 6.5]

516.36 Equipment and Containers in Ventilated Areas.

Open containers, supply containers, waste containers, and solvent distillation units that contain Class Iliquids shall be located in areas ventilated in accordance with 516.4 .

516.37 Luminaires.

For printing, coating and dipping equipment where the process area is enclosed by glass panels that aresealed to confine vapors and mists to the inside of the enclosure, luminaires that are attached to thewalls or ceilings of a process enclosure and that are located outside of any classified area shall bepermitted to be of general purpose construction. Such luminaires shall be serviced from outside theenclosure.

Luminaires that are attached to the walls or ceilings of a process enclosure, are located within the ClassI, Division 2 or Class I, Zone 2 location, and are separated from the process area by glass panels thatare sealed to confine vapors and mists shall be suitable for use in that location. Such fixtures shall beserviced from outside the enclosure.


(A) Wiring.

All fixed wiring above the Class I and II locations shall be in metal raceways, Type PVC conduit, TypeRTRC conduit, or electrical nonmetallic tubing; where cables are used, they shall be Type MI, Type TC,or Type MC cable. Cellular metal floor raceways shall only be permitted to supply ceiling outlets or asextensions to the area below the floor of a Class I or II location. Where cellular metal raceways, areused, they shall not have connections leading into or passing through the Class I or II location unlesssuitable seals are provided.

(B) Equipment.

Equipment that is capable of producing arcs, sparks, or particles of hot metal, such as lamps andlampholders for fixed lighting, cutouts, switches, receptacles, motors, or other equipment havingmake-and-break or sliding contacts, where installed above a classified location or above a locationwhere freshly finished goods are handled, shall be of the totally enclosed type or be constructed so asto prevent the escape of sparks or hot metal particles.


268 of 270 4/16/2015 11:12 AM

516.40 Static Electric Discharges.

All persons and all electrically conductive objects, including any metal parts of the process equipment orapparatus, containers of material, exhaust ducts, and piping systems that convey flammable orcombustible liquids, shall be electrically grounded.

Provision shall be made to dissipate static electric charges from all nonconductive substrates in printingprocesses.

Informational Note: For additional guidance on reducing the risk of ignition from electrostaticdischarges, see NFPA 77 -2014, Recommended Practice on Static Electricity .



516_3956_BC.docx




Street Address:

City:

State:

Zip:


Committee Statement

CommitteeStatement:

This is a complete revision of Article 516. This revision aligns with the 2015 versions of NFPA 33and NFPA 34. This proposal was developed by a task group of the NFPA Committee on FinishingProcesses.

The defined terms for "Flash-Off Area" and "Resin Application Area" were deleted because theterms were not used in the Code.

ResponseMessage:

Public Input No. 4242-NFPA 70-2014 [Section No. 516.10(A) [Excluding any Sub-Sections]]

Public Input No. 21-NFPA 70-2013 [Global Input]

Public Input No. 4266-NFPA 70-2014 [Article 516]

Public Input No. 1811-NFPA 70-2014 [Definition: Resin Application Area.]

Public Input No. 1810-NFPA 70-2014 [Definition: Flash-Off Area.]


Ballot Results


16 Eligible Voters

1 Not Returned

14 Affirmative All



0 Abstention

Not Returned


269 of 270 4/16/2015 11:12 AM

Cahill, Corey

Affirmative All


Ankele, Donald W.

Bernsen, Marc J.

Blais, Steven J.

Burns, Dave

Jones, Robert A.

Kines, Haywood


Massey, L. Evans

McBride, William E.

Neagle, Jeremy

Parks, Ryan

Simmons, John L.

Wechsler, David B.


Wirfs, Mark C.

NONE>


270 of 270 4/16/2015 11:12 AM

National Fire Protection Association Report … · National Fire Protection Association 1 Batterymarch Park, Quincy, MA 02169-7471 ... The definition for “process seal” is contained

Documents