report on proposals – june 2013 nfpa 70 … · ansi/isa–tr12.21.01, ... report on proposals –...

Report on Proposals – June 2013 NFPA 70_______________________________________________________________________________________________14-1 Log #1170m NEC-P14

_______________________________________________________________________________________________Russell LeBlanc, The Peterson School

In articles 90 through 830, if the wording is not already there, then add the words (or otherstructure(s)) after the word BUILDING(S) wherever the intent of the requirement is to also include STRUCTURES aswell as buildings.

There is a flaw in the NEC. The term "building" is used over 1000 times in the NEC, and in most of thecases the words "or other structure" should follow and apply the same requirements to bridges, billboards, towers,tanks, and other structures that are by definition NOT BUILDINGS. One specific example I can use is section 225.10Wiring onBuildings. I believe that this section is also intended to be applied structures, but the wording "or other structures" is notin the heading or the paragraph. There are literally thousands of other instances throughout the code that this sameproblem exists. This can easily be seen by doing an electronic search for the word "building". In some cases the words"or other structure" (or similar wording) are present, but in the vast majority where the requirements should also beapplied to structures other than buildings, the wording is not there.

The submitter has not provided specific proposed text for his proposal in accordance with 4.3.3(c)of the Regulations Governing Committee Projects.

_______________________________________________________________________________________________14-2 Log #921m NEC-P14

_______________________________________________________________________________________________Joe Tedesco, Boston, MA

The term "adequate" and "adequately" and "inadequately" and "inadequate" should be replacedwith terms that can be properly enforced and understood.

Terms are not defined and are considered vague and unenforceable per Table 3.2.1 in the NEC StyleManaual. They are all "incorrect" 148 times in the NEC.

The submitter has not provided specific proposed text for his proposal in accordance with 4.3.3(c)of the Regulations Governing Committee Projects.

1Printed on 1/23/2012

Report on Proposals – June 2013 NFPA 70_______________________________________________________________________________________________14-3 Log #2638e NEC-P14

_______________________________________________________________________________________________John R. Kovacik, Underwriters Laboratories Inc.

Update the references to UL Standards in the Informational Notes as shown below:

Equipment enclosed in a case that is capable of withstanding an explosion of a specifiedgas or vapor that may occur within it and of preventing the ignition of a specified gas or vapor surrounding the enclosureby sparks, flashes, or explosion of the gas or vapor within, and that operates at such an external temperature that asurrounding flammable atmosphere will not be ignited thereby.Informational Note: For further information, see ANSI/UL

1203-2006 2009,

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

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 or atmosphericsuspensions of a specified dust on or in the vicinity of the enclosure.Informational Note: For further information on dustignitionproof enclosures, see Type 9 enclosure in ANSI/NEMA

250-1991, , and ANSI/UL 1203-1994 2009,.

Informational Note: For further information, see ANSI/UL 1203-1994 2009,.

Informational Note No. 2: Female NPT threaded entries use a modified National Standard Pipe Taper (NPT) thread withthread form per ANSI/ASME B1.20.1-1983,

. See ANSI/UL 1203 2009,.

A circuit in which 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: Test conditions are described in ANSI/UL 913-1997 2006,

.For purposes of this article, the following definitions apply.Equipment enclosed in a manner that excludes dusts and does not permit arcs, sparks, or heat

otherwise generated 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 enclosures, see Type 9 enclosure in ANSI/NEMA

250-1991, , and ANSI/UL 1203-1994 2009,.

References to UL Standards in the NEC should reflect the current edition.

Accept all amendments to the publication dates of the referenced documents, but do not accept the deletion of "1203"in Informational Note 2 of 500.2(1).

The panel notes that the submitter accidentally deleted the document number.


Report on Proposals – June 2013 NFPA 70_______________________________________________________________________________________________14-4 Log #1611 NEC-P14

_______________________________________________________________________________________________James F. Williams, Fairmont, WV

Revise text to read as follows:

That portion of a property where liquids are received by tank vessel, pipelines, tank car, ortank vehicle and are stored or blended in bulk for the purpose of distributing such liquids by tank vessel, pipeline, tankcar, tank vehicle, portable tank, or container. [ 3.3.32.1]Informational Note: For further information, see NFPA 30-2008, .

That portion of a property where liquids are received by tank vessel, pipelines, tank car, ortank vehicle and are stored or blended in bulk for the purpose of distributing such liquids by tank vessel, pipeline, tankcar, tank vehicle, portable tank, or container. [ 3.3.32.1]Informational Note: For further information, see NFPA 30-2008, .

The defined term is referenced in several articles of the NEC: , , , ,, &

In general, Article 100 shall contain definitions of terms that appear in two ormore other articles of the .

The Tables cited in the submitter’s substantiation contain references to Chapter 5 articles. The term“bulk plant” appears only in Article 515. The present location of the definition is correct.





Equipment with electrical components suitable to be moved only with mechanical aids or isprovided with wheels for movement by person(s) or powered devices.

Equipment with electrical components suitable to be moved by a single person withoutmechanical aids

Equipment with electrical components suitable to be moved only with mechanical aids or isprovided with wheels for movement by person(s) or powered devices.

Equipment with electrical components suitable to be moved by a single person withoutmechanical aids

The defined term is referenced in several articles of the NEC: , ,, , , , , , , , ,

(3), , , , , , , (2), , 513.2, & 513., , , (8), , , , ,

, (1), (5), , ,(6), , , , , , , ,

, , , , , , , , ,, , , , , , ,

, , , , ,, , , , , , , &


The submitter did not provide substantiation to support the correctness of the proposed definitions.This is not in accordance with 4.3.3(d) of the Regulations Governing Committee Projects. Panel 14 also notes that“portable” and “movable” vary from product to product, and are defined in the various product standards.





That portion of a property where motor fuels are stored and dispensed from fixedequipment into the fuel tanks of motor vehicles or marine craft or into approved containers, including all equipment usedin connection therewith. [ 3.3.11]Informational Note: Refer to Articles 510 and 511 with respect to electrical wiring and equipment for other areas used

as lubritoriums, service rooms, repair rooms, offices, salesrooms, compressor rooms, and similar locations.

That portion of a property where motor fuels are stored and dispensed from fixedequipment into the fuel tanks of motor vehicles or marine craft or into approved containers, including all equipment usedin connection therewith. [ 3.3.11]Informational Note: Refer to Articles 510 and 511 with respect to electrical wiring and equipment for other areas used

as lubritoriums, service rooms, repair rooms, offices, salesrooms, compressor rooms, and similar locations.The defined term is referenced in several articles of the NEC: , , , ,

, , , , , , &In general, Article 100 shall contain definitions of terms that appear in two or

more other articles of the .

The Tables cited in the submitter’s substantiation contain references to Chapter 5 articles. Theterm “motor fuel dispensing facility” appears only in Article 514. The present location of the definition is correct.

_______________________________________________________________________________________________14-7 Log #2894 NEC-P14



Equipment with electrical components intended to be moved from one place to another.

Equipment with electrical components suitable to be moved by a single person withoutmechanical aids.

The defined term is referenced in several articles of the NEC: 100 I Electric Sign, 110, 210, 250, 368,400, 430, 490, 500, 501, 505, 511, 513, 514, 515, 516, 517, 518, 520, 525, 530, 545, 600, 640, 668, 680It is defined in 513.2, 520.2, 530.2, 640.2, & 680.2. Suggest that a single definition in 100 I is better.


The submitter did not provide substantiation to support the correctness of the proposed definition.This is not in accordance with 4.3.3(d) of the Regulations Governing Committee Projects. Panel 14 also notes that themeaning of “portable” varies from Article to Article. The panel notes that the proposed change in the definition wouldhave unintended and unsubstantiated changes to the application of portable equipment in aircraft hangars.





An enclosure or insert within a larger room used for spray/coating/dipping applications. A spray boothmay be fully enclosed or have open front or face and may include separate conveyor entrance and exit. The spray boothis provided with a dedicated ventilation exhaust but may draw supply air from the larger room or have a dedicated airsupply.


The defined term is referenced in several articles of the NEC: (3)(2), , &In general, Article 100 shall contain definitions of terms that appear in two or

more other articles of the .

The citation of 500.5(B)(3) by the submitter in the substantiation is an Informational Note, not in theCode text. This does not justify moving the definition from Article 516 to Article 100, as Article 516 is the only Articlecontaining provisions for spray booths.



_______________________________________________________________________________________________Eliana Brazda, ISA

Add new text to read as follows:Electromagnetic radiation at wavelengths in vacuum between the region of transition to X-rays and

the region of transition to radio waves, that is approximately between 1 nm and 1,000 ìm. Informational Note: Foradditional information on types of protection that can be applied to minimize the risk of ignition in explosive gasatmospheres from optical radiation in the wavelength range from 380 nm to 10 µm, see ANSI/ISA–TR12.21.01,

Type of protection to minimize the risk of ignition in explosive gas atmospheresfrom optical radiation where visible or infrared radiation is incapable of producing sufficient energy under normal orspecified fault conditions to ignite a specific hazardous atmospheric mixture. Informational Note: SeeANSI/ISA–TR12.21.01,

Type of protection to minimize the risk of ignition in explosive gas atmospheres fromoptical radiation where radiation is confined inside optical fibre or other transmission medium under normalconstructions or constructions with additional mechanical protection based on the assumption that there is no escape ofradiation from the confinement. Informational Note: See ANSI/ISA–TR12.21.01,

Type of protection to minimize the risk of ignition in explosive gas atmospheres fromoptical radiation where radiation is confined inside protected or unprotected optical fibre or other transmission mediumwith interlock cut-off provided to reliably reduce the unconfined beam strength to safe levels within a specified time.Informational Note: See ANSI/ISA–TR12.21.01,

Optical fibre cable protected from releasing optical radiation into the atmosphereduring normal operating conditions and foreseeable malfunctions by additional armouring, conduit, cable tray orraceway. Informational Note: See ANSI/ISA–TR12.21.01,

· The 2011 edition of the NEC does not address the potential for optical radiation to cause ignition in anexplosive atmosphere. It does address optical fiber cables, but not from the perspective of the potential to causeignition.· ANSI/ISA-TR12.21.01, , containspublished US national requirements that address the potential risk of ignition associated with optical radiation in Divisionclassified areas.· This ANSI/ISA standard is aligned with harmonized with ANSI/ISA-60079-28 (12.21.02),

, and IEC/EN60079-28:2006,

, for Zone classified areas.· ANSI/ISA-TR12.21.01 defines three types of protection that can be applied to address the potential for opticalradiation to cause ignition in potentially explosive atmospheres. These types of protection are: 1) inherently safe opticalradiation; 2) protected optical radiation; and 3) optical system with interlock.· This proposal introduces these types of protection, along with the general term ‘optical radiation’ and one of themore common applications of optical radiation in explosive atmospheres, ‘protected optical fiber cable’.· Additional proposals are being submitted to introduce related, supporting text under 500.7 and 501.155.· It should be noted that the sources of the optical radiation are electrical equipment. Therefore this proposal isnecessary for inclusion in the NEC.

There is no need to define terms that are not used in the Code.




Revise text to read as follows:Dusttight Informational Note: ANSI/ISA-12.12.01-2007,

ANSI/ISA-12.12.01,

Electrical and Electronic Equipment: ISA-RP12.12.03-2002,

ANSI/ISA-12.12.03,.

Hermetically Sealed Informational Note: ANSI/ISA-12.12.01-2007,ANSI/ISA-12.12.01,

Nonincendive Circuit Informational Note: ANSI/ISA-12.12.01-2007,ANSI/ISA-12.12.01,

Nonincendive Component Informational Note: ANSI/ISA-12.12.01-2007,ANSI/ISA-12.12.01,

Nonincendive Equipment Informational Note: ANSI/ISA-12.12.01-2007ANSI/ISA-12.12.01,

Nonincendive Field Wiring Apparatus Informational Note: ANSI/ISA-12.12.01-2007,

ANSI/ISA-12.12.01,

Remove the ISA standards date of publication to allow application of all appropriate versions.

Accept the changes proposed by the submitter, but include the appropriate publication dates of 2011. The tworeferences will read:ANSI/ISA-12.12.01-2011,

andANSI/ISA-12.12.03-2011,

Paragraph 3.3.7.4 of the Regulations Governing Committee Projects requires dated references toStandards. The current publication dates for ISA 12.12.01 and 12.12.03 are 2011.



_______________________________________________________________________________________________Marcelo M. Hirschler, GBH International

Revise text to read as follows: Apparatus in which the circuits are not necessarily nonincendive

themselves but that affect the energy in nonincendive field wiring circuits and are relied upon to maintain nonincendiveenergy levels. Associated nonincendive field wiring apparatus may be either 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

Associated nonincendive field wiring apparatus has designated associated nonincendive fieldwiring apparatus connections for nonincendive field wiring apparatus and may also have connections for other electricalapparatus.

: Associated nonincendive field wiring apparatus may be either 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

The NFPA Manual of Style requires definitions to be in single sentences. The information provided inthe subsequent sentences is not really a part of the definition; it is further information that is best placed in aninformational note.

Paragraph 2.3.2.2 of the NFPA Manual of Style does not require definitions in the form of a singlesentence; it requires definitions in the form of a single paragraph unit. The NEC Style Manual does not modify this.

_______________________________________________________________________________________________14-11a Log #CP1411 NEC-P14

_______________________________________________________________________________________________Code-Making Panel 14,

In 500.2 replace the current definition of Combustible Dust with the following:Combustible Dust. Dust particles of 500 microns or smaller (material passing a U.S. No. 35 Standard Sieve as defined

in ASTM E 11, Standard Specification for Wire Cloth and Sieves for Testing Purposes) are considered to present a dustfire or dust explosion hazard unless determined otherwise. (See ASTM E 1226 or ISO 6184/1). [499:3.3.3]

Definition is extracted from NFPA 499 and the definition in the 2012 Edition of NFPA 499 has beenrevised.

_______________________________________________________________________________________________14-11b Log #CP1402 NEC-P14


Add a new definition to 500.2, 505.2, and 506.2 to read:Cord Connector. A fitting intended to terminate a cord to a box or similar device and reduce the strain at points of

termination and may include an explosionproof, a dust ignition proof, or a flameproof seal.The existing term "cord connector" has different meanings in other places, which has caused

confusion. The inclusion of this definition in these three articles makes it clear as to the meaning of the term as amechanical device, not as an electrical device, and is based on the product standard ANSI/UL 514B.




Revise text to read as follows: A component having contacts for making or breaking an incendive circuit and the

contacting mechanism is constructed so that the component is incapable of igniting the specified flammable gas–air orvapor–air mixture. The housing of a nonincendive component is not intended to exclude the flammable atmosphere orcontain an explosion.

For further information, see ANSI/ISA-12.12.01-2007,

: The housing of a nonincendive component is not intended to exclude the flammableatmosphere or contain an explosion.



_______________________________________________________________________________________________14-13 Log #1221 NEC-P14


Revise text to read as follows: Wiring that enters or leaves an equipment enclosure and, under normal operating

conditions of the equipment, 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.

: Normal operation includes opening, shorting, or grounding the field wiring.The NFPA Manual of Style requires definitions to be in single sentences. The information provided in

the subsequent sentences is not really a part of the definition; it is further information that is best placed in aninformational note.


_______________________________________________________________________________________________14-14 Log #3186 NEC-P14

_______________________________________________________________________________________________Stephen Crimaudo, American Petroleum Institute

Replace "1997" date reference to ANSI/API RP500 to "2012" as indicated below.ANSIAPI RP500-1997 2012,

I,This and the companion proposals propose to update the date references to ANSI/API RP 500. The

latest edition of ANSI/API RP 500 has been approved for publication and is expected to be published by API in early2012.

The 2012 edition of the referenced document has not been published yet.




Replace "1997" date reference to ANSI/API RP500 to "2012" as indicated below., Informational Note No. 4: For further information on ventilation, see NFPA 30-2008,

and API RP 500- 1997 2012This and the companion proposals propose to update the date references to ANSI/API RP 500. The

latest edition of ANSI/API RP 500 has been approved for publication and is expected to be published by API in early2012.


_______________________________________________________________________________________________14-15a Log #CP1413 NEC-P14


Revise text to read as follows:500.5 Classifications of Locations(A) Classifications of Locations. 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. Where pyrophoricmaterials are the only materials used or handled, these locations shall not be classified. Each room, section, or areashall be considered individually in determining its classification. Where pyrophoric materials are the only materials usedor handled, these locations are outside the scope of this article.

The language is being updated to be consistent with current language found in Section 506.5(A) andconsistent with the fact that neither NFPA 497 or NFPA 499 currently address the use of pyrophoric materials.



_______________________________________________________________________________________________Billy Breitkreutz, Fluor Corporation

Add an Informational Note No. 3 to read as follows:“Informational Note No. 3: Pyrophoric materials should be in containment systems designed to prevent contact

between the pyrophoric material and air. The pyrophoric material might escape in very small amounts and combine withair at a level and temperature that would not cause spontaneous combustion. Ignition might be avoided if electricalequipment in the area is suitable for a classified location.”

Silane (SiH4) is a pyrophoric gas that will not spontaneously ignite when mixed with air at a low leveland temperature. Silane must be loaded into containers for transportation using a connection that might leak a verysmall quantity and mix with air at such a low level and temperature. Code Section 505.5(A) prohibits classification of thearea. The Code does not prohibit installation of equipment suitable for a hazardous area in the non-hazardous area.The proposed change will make clear that installation of equipment suitable for a hazardous area in this non-hazardousis a recognized practice.

The methods of protection identified in Articles 500, 505, and 506 do not provide a sufficient degreeof protection for pyrophoric material. Pyrophoric materials are specifically excluded from the scopes of NFPA 497,

, and NFPA 499,

.

_______________________________________________________________________________________________14-17 Log #2167 NEC-P14



ASTM D3175: new date is 2011

Standards update.

This is extracted text and cannot be altered by Panel 14.

_______________________________________________________________________________________________14-18 Log #3188 NEC-P14


Change "ignition temperature" to "autoignition temperature".API RP 500, API RP 505, NFPA 497 and NFPA 499 define the term "Autoignition Temperature" or

(AlT). The term "ignition temperature" is often used synonymously with autoignition temperature, but sometimesincorrectly. This proposal, along with its companion proposals, attempt to promote consistency of the terms between thestandards. The term "autoignition temperature" is used when referring to the material property of flammable liquids andvapors, which is consistent with how the term is used in NFPA497. The term "ignition temperature" is used when referring to the material property of combustible dusts, which isconsistent with how the term is used in NFPA 499.



_______________________________________________________________________________________________Jeremy Neagle, US Bureau of Alcohol, Tobacco, Firearms & Explosives

Revise text to read as follows:Informational Note No. 3: Certain dusts may require additional precautions due to chemical phenomena that can result

in the generation of ignitible gases. See ANSI/IEEE C2-20122007, , Section 127A, CoalHandling Areas.

IEEE is the organization responsible for the development of the National Electrical Safety Code. Thecurrent edition is 2012. This document is referenced in various sections throughout the NEC as either ANSI C2 orANSI/IEEE C2. I suggest the NEC Technical Correlating Committee review these sections (110.31, 110.71, 225.1,225.60, 225.61, 230.200, 399.10, 450.27, 500.6, 800.44, 800.90, 820.44, 830.44, 840.44) and update as appropriate.




Add new text to read as follows:This protection technique shall be permitted for equipment in Class I, Division 1

or 2 locations, for which it is identified.The identified Division depends upon the number of faults applied as part of the protection

technique evaluation.This protection technique shall be permitted for equipment in Class I, Division 1 or 2

locations, for which it is identified.The identified Division depends upon whether or not additional mechanical protection is provided as

part of the protection technique evaluation.This protection technique shall be permitted for equipment in Class I, Division 1 or

2 locations, for which it is identified.The identified Division depends upon the confinement construction and upon the shut-down time in

which the unconfined beam strength is reliably reduced to safe levels.● The 2011 edition of the NEC does not address the potential for optical radiation to cause ignition in

an explosive atmosphere. It does address optical fiber cables, but not from the perspective of the potential to causeignition.● ANSI/ISA-TR12.21.01, , contain published

US national requirements that address the potential risk of ignition associated with optical radiation in Division classifiedareas.● This ANSI/ISA standard is aligned with harmonized with ANSI/ISA-60079-28 (12.21.02),

, and IEC/EN 60079-28:2006,, for Zone

classified areas.● ANSI/ISA-TR12.21.01 defines three types of protection that can be applied to address the potential for optical

radiation to cause ignition in potentially explosive atmospheres. These types of protection are: 1) inherently safe opticalradiation; 2) protected optical radiation; and 3) optical system with interlock.● This proposal introduces these types of protection, along with the general term ‘optical radiation’ and one of the

more common applications of optical radiation in explosive atmospheres, ‘protected optical fiber cable’.● Additional proposals are being submitted to introduce related, supporting text under 500.2 and 501.155.It should be noted that the sources of the optical radiation are electrical equipment. Therefore this proposal is

necessary for inclusion in the NEC.

The technical report referenced in the substantiation does not establish that the testing criteriaprovided are indicative of typical installations in hazardous (classified) locations and there is no evidence that existingequipment in use should be tested to these additional standards.



_______________________________________________________________________________________________Jon D. Miller, Detector Electronics Corp.

Change the text to the following :(1) Inadequate Ventilation. In a Class I, Division 1 location that is so classified due to inadequate ventilation, electrical

equipment suitable for Class I, Division 2 locations shall be permitted. Combustible gas detection equipment shall belisted for Class I, Division 1, for the appropriate material group, and for the detection of the specific gas or vapor to beencountered for which it is intended.( 2) Interior of a Building. In a building located in, or with an opening into, a Class I, Division 2 location where the

interior does not contain a source of flammable gas or vapor, electrical equipment for unclassified locations shall bepermitted. Combustible gas detection equipment shall be listed for Class I, Division 1 or Class I, Division 2, for theappropriate material group, and for the detection of the specific gas or vapor to be encountered for which it is intended.( 3) Interior of a Control Panel. In the interior of a control panel containing instrumentation utilizing or measuring

flammable liquids, J gases, or vapors, electrical equipment suitable for Class I, Division 2 locations shall be permitted.Combustible gas detection equipment shall be listed for Class I, Division 1, for the appropriate material group, and forthe detection of the specific gas or vapor to be encountered for which it is intended.

The listing of the gas detector would include the gasses or vapors for which the detector is intended(not "encountered"). A Methane gas detector encounters Nitrogen (within air), but the Methane gas detector is not listedfor Nitrogen.

Gas detection equipment can be intended to detect, for example, a noncombustible gas or acombustible gas other than the one to be encountered, and that would not fulfill the requirements of using gas detectionas a method of protection.

_______________________________________________________________________________________________14-22 Log #3189 NEC-P14




The more general term "ignition temperature" is appropriate here, since this section addressesgases, vapors, dusts, and fibers/flyings.






_______________________________________________________________________________________________14-24 Log #2056 NEC-P14

_______________________________________________________________________________________________Edward M. Briesch, Underwriters Laboratories Inc.

Revise text to read as follows:The marking shall specify the temperature class or operating temperature at a 40°C

ambient temperature, or at the higher ambient temperature if the equipment is rated and marked for an ambienttemperature of greater than 40°C. For equipment installed in a Class II, Division 1location, the temperature class oroperating temperature shall be based on operation of the equipment when blanketed with dust. The temperature class,if provided, shall be indicated using the temperature class (T Codes) shown in Table 500.8(C). Equipment for Class Iand Class II shall be marked with the maximum safe operating temperature, as determined by simultaneous exposure tothe combinations of Class I and Class II conditions.

The current text is not clear as to if this temperature is based on operation of the equipment in free airor when the equipment is blanketed with dust. In a Class II, Division 1 location, it would be expected that a dust blanketcould exist under normal operating conditions. Equipment temperatures under a dust blanket will be considerably higherthan in free air due to the insulating effect of the dust blanket and may very well exceed the ignition temperature of thedust when in free air they would not. The ANSI standards for the equipment, ANSI/UL1203 for example, require thetemperature be determined with a dust blanket.

Revise text to read as follows:The marking shall specify the temperature class or operating temperature at a 40°C

ambient temperature, or at the higher ambient temperature if the equipment is rated and marked for an ambienttemperature of greater than 40°C. For equipment installed in a Class II, Division 1 location, the temperature class oroperating temperature shall be based on operation of the equipment when blanketed with the maximum amount of dustthat can accumulate on the equipment. The temperature class, if provided, shall be indicated using the temperatureclass (T Codes) shown in Table 500.8(C). Equipment for Class I and Class II shall be marked with the maximum safeoperating temperature, as determined by simultaneous exposure to the combinations of Class I and Class II conditions.

The proposed text has been amended to provide a quantifiable measure of a blanket of dust.






_______________________________________________________________________________________________14-26 Log #3192 NEC-P14






_______________________________________________________________________________________________

Richard A. Janoski, Finleyville, PARevise text to read as follows:

(1) For equipment provided withthreaded entries for NPT threaded conduit or fittings, listed conduit, listed conduit fittings, or listed cable fittings shall beused.

As 500.8(E)(1) is presented in the 2008 NEC, a grammatical error leaves the conduit fittings and thecable fittings without a rule that requires them to be listed. The word “listed” is only preceding the word “conduit”,therefore it only applies to the conduit. The addition of the word “listed” preceding the conduit fittings, and the cablefittings will add the necessary listing requirement. This will also provide continuity between the proposed text for500.8(E)(1) and 500.8(E)(2).



_______________________________________________________________________________________________Donald W. Ankele, Underwriters Laboratories Inc.

Revise text to read as follows:Metric threaded entries into explosionproof equipment shall have a class of fit of at least 6g/6H and shall be madeup

with at least five threads fully engaged for Group C andGroup D, and at least eight threads fully engaged for Group A and Group B. and thread engagement as shown in Table500.8(E)(3).*** Insert Table 500.9(E)(3) here***

Revise the class of fit to align with the requirements in ANSI standards for explosionproof equipmentand to provide gauging requirements for field tapping of entries into unlisted equipment.

The panel has determined that it would be best to address this issue in the individual productstandards.




Add text to read as follows:

(a)

(6) In industrial establishments with restricted public access, where the conditions of maintenance and supervisionensure that only qualified persons service the installation and where metallic conduit (RMC) does not provide sufficientcorrosion resistance, listed reinforced thermosetting resin conduit (RTRC), factory elbows, and associated fittings, allmarked with the suffix -XW, and Schedule 80 PVC conduit, factory elbows, and associated fittings shall be permitted.Where seals are required for boundary conditions as defined in 501.15(A)(4), the Division 1 wiring method shall extendinto the Division 2 area to the seal, which shall be located on the Division 2 side of the Division 1–Division 2 boundary.

In each conduit run passing from a Class I, Division 2 location into an unclassifiedlocation. The sealing fitting shall be permitted on either side of the boundary of such location within 3.05 m (10 ft) of theboundary. Rigid metal conduit (RMC) or threaded steel intermediate metal conduit shall be used between the sealingfitting and the point at which the conduit leaves the Division 2 location, and a threaded connection shall be used at thesealing fitting. Except for listed reducers at the conduit seal, there shall be no union, coupling, box, or fitting between theconduit seal and the point at which the conduit leaves the Division 2 location. Conduits shall be sealed to minimize theamount of gas or vapor within the Division 2 portion of the conduit from being communicated to the conduit beyond theseal. Such seals shall not be required to be explosion-proof but shall be identified for the purpose of minimizing passageof gases under normal operating conditions and shall be accessible.

The cross-sectional area of the conductors permitted in a seal shall not exceed 25 percent of thecross-sectional area of a rigid metal conduit (RMC) of the same trade size unless it is specifically identified for a higherpercentage of fill.

Pendant luminaires shall be suspended by and supplied through threaded rigid metal conduit(RMC) stems or threaded steel intermediate conduit stems, and threaded joints shall be provided with set-screws orother effective means to prevent loosening. For stems longer than 300 mm (12 in.), permanent and effective bracing


Report on Proposals – June 2013 NFPA 70against lateral displacement shall be provided at a level not more than 300 mm (12 in.) above the lower end of the stem,or flexibility in the form of a fitting or flexible connector identified for the Class I, Division 1 location shall be provided notmore than 300 mm (12 in.) from the point of attachment to the supporting box or fitting.

Pendant luminaires shall be suspended by threaded rigid metal conduit (RMC) stems,threaded steel intermediate metal conduit stems, or other approved means. For rigid stems longer than 300 mm (12 in.),permanent and effective bracing against lateral displacement shall be provided at a level not more than 300 mm (12 in.)above the lower end of the stem, or flexibility in the form of an identified fitting or flexible connector shall be provided notmore than 300 mm (12 in.) from the point of attachment to the supporting box or fitting.

"Rigid Metal Conduit" is also referred to as “RMC” “Metallic Conduit”Suggest that "RMC" be added to all references. This will make finding all references to "Rigid Metal Conduit" easier

and more reliable.

There was no technical substantiation provided with the proposal to justify the insertion of theacronym in each location within this article where the wiring method is used. Section 3.2.3 of the NEC Style Manualpermits, but does not require, an acronym to be used within an article. Adding the acronym to the wiring method doesnot increase usability or reliability.





(a)

(6) In industrial establishments with restricted public access, where the conditions of maintenance and supervisionensure that only qualified persons service the installation and where metallic conduit (IMC) does not provide sufficientcorrosion resistance, listed reinforced thermosetting resin conduit (RTRC), factory elbows, and associated fittings, allmarked with the suffix -XW, and Schedule 80 PVC conduit, factory elbows, and associated fittings shall be permitted.Where seals are required for boundary conditions as defined in 501.15(A)(4), the Division 1 wiring method shall extendinto the Division 2 area to the seal, which shall be located on the Division 2 side of the Division 1–Division 2 boundary.

In each conduit run passing from a Class I, Division 2 location into an unclassifiedlocation. The sealing fitting shall be permitted on either side of the boundary of such location within 3.05 m (10 ft) of theboundary. Rigid metal conduit or threaded steel intermediate metal conduit (IMC) shall be used between the sealingfitting and the point at which the conduit leaves the Division 2 location, and a threaded connection shall be used at thesealing fitting. Except for listed reducers at the conduit seal, there shall be no union, coupling, box, or fitting between theconduit seal and the point at which the conduit leaves the Division 2 location. Conduits shall be sealed to minimize theamount of gas or vapor within the Division 2 portion of the conduit from being communicated to the conduit beyond theseal. Such seals shall not be required to be explosion-proof but shall be identified for the purpose of minimizing passageof gases under normal operating conditions and shall be accessible.

Pendant luminaires shall be suspended by and supplied through threaded rigid metal conduitstems or threaded steel intermediate conduit (IMC) stems, and threaded joints shall be provided with set-screws or othereffective means to prevent loosening. For stems longer than 300 mm (12 in.), permanent and effective bracing againstlateral displacement shall be provided at a level not more than 300 mm (12 in.) above the lower end of the stem, orflexibility in the form of a fitting or flexible connector identified for the Class I, Division 1 location shall be provided notmore than 300 mm (12 in.) from the point of attachment to the supporting box or fitting.


Report on Proposals – June 2013 NFPA 70Pendant luminaires shall be suspended by threaded rigid metal conduit stems, threaded

steel intermediate metal conduit (IMC) stems, or other approved means. For rigid stems longer than 300 mm (12 in.),permanent and effective bracing against lateral displacement shall be provided at a level not more than 300 mm (12 in.)above the lower end of the stem, or flexibility in the form of an identified fitting or flexible connector shall be provided notmore than 300 mm (12 in.) from the point of attachment to the supporting box or fitting.

"Intermediate Metal Conduit" is also referred to as “IMC” “Metallic Conduit”Suggest that "IMC" be added to all references. This will make finding all references to “Intermediate Metal Conduit"

easier and more reliable.

See panel action and statement on Proposal 14-29.




Wiring methods shall comply with 501.10(A) or (B).

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

(b) Type MI cable shall be installed and supported in amanner to avoid tensile stress at the termination fittings.(c) where the conditions of maintenance and supervision

ensure that only qualified persons service the installation,Type MC-HL cable listed for use in Class I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugated

metallic sheath, an overall jacket of suitable polymericmaterial, and a separate equipment grounding conductor(s) in accordance with 250.122, and terminated with fittingslisted for the application.Type MC-HL cable shall be installed in accordance with the provisions of Article 330, Part II.(d) where the conditions of maintenance and supervision

ensure that only qualified persons service the installation,Type ITC-HL cable listed for use in Class I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugatedmetallic sheath and an overall jacket of suitablepolymeric material, and terminated with fittings listed for the application, and installed in accordance with the provisionsof Article 727.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .Where necessary to employ flexible connections, as at motor terminals, flexible fittings listed

for the location, or flexible cord in accordance with the provisions of 501.140 terminated with cord connectors listed forthe location, shall be permitted.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors,see UL 2225, .

All boxes and fittings shall be approved for Class I, Division 1.

In Class I, Division 2 locations, the following wiring methods shall be permitted:(1) All wiring methods permitted in 501.10(A).(2) Enclosed gasketed busways and enclosed gasketed wireways.(3) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, including installation in cable

tray systems. The cable shall be terminatedwith listed fittings.(4) Type ITC and Type ITC-ER cable as permitted in 727.4 and terminated with listed fittings.(5) Type MC, MV, or TC cable, including installation in cable tray systems. The cable shall be terminated with listed

fittings.where the conditions of maintenance and supervision ensure that only qualified persons service the installation and

where metallic conduit does 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, factoryelbows, and associated fittings shall be permitted.Where seals are required for boundary conditions as defined in 501.15(A)(4), the Division 1 wiring method shall extend

into the Division 2 area to the seal, which shall be located on the Division 2 side of the Division 1–Division 2 boundary.


Report on Proposals – June 2013 NFPA 70

(2) Flexible Connections. Where provision must be made for limited flexibility, one or more of the following shall bepermitted:(1) Listed flexible metal fittings.(2) Flexible metal conduit with listed fittings.(3) Liquidtight flexible metal conduit with listed fittings.(4) Liquidtight flexible nonmetallic conduit with listed fittings.(5) Flexible cord listed for extra-hard usage and terminated with listed fittings. A conductor for use as an equipment

grounding conductor shall be included in the flexible cord.Informational Note 1: See 501.30(B) for grounding requirements where flexible conduit is used.

Revise to add an Informational Note regarding the requirements for cables, cable fittings and cordconnectors. There have been several instances of confusion regarding these Code requirements with respect totermination of cables with cable fittings.

Accept the addition of two informational notes as follows:Informational Note: For entry into enclosures required to be explosionproof, see further information on construction,

testing and marking of cables, explosionproof cable fittings, and explosionproof cord connectors in ANSI/UL 2225-2011,Cables and Cable-Fittings for Use in Hazardous (Classified) Locations.The first addition is intended to follow 501.10 (A)(3) and the second is intended to follow 501.10 (B)(4).

The text was amended to clarify when the informational note is relevant and relocated to theappropriate sections. The title of the referenced document has been corrected to indicate ANSI approval and thepublication date has been added, in accordance with Paragraph 3.3.7.4 of the Regulations Governing CommitteeProjects.

_______________________________________________________________________________________________14-32 Log #2607 NEC-P14

_______________________________________________________________________________________________Richard A. Holub, The DuPont Company, Inc.

Add new text to read as follows:(e) Fiber Optic cables of the types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall be permitted to

be installed in raceways as stated in 501.10(A). These Fiber Optic cables shall be sealed in accordance with 501.15.These proposals are a result of an ad-hoc task team consisting of members of CMP3, CMP14, and

CMP16, along with industry representatives. Members of this task team included Rich Holub, Dave Wechsler, BobPotter, Bob Walsh, Harry Ohde, Terry Coleman, and Will Miller.Section 770.3(A) currently permits the use of Fiber Optic cables in hazardous (classified) locations if sealed in

accordance with Sections 501.15, 502.15, 505.16, and 506.16. This proposal adds the requirements in Chapter 5 forcorrelation as Chapter 7 is not allowed to modify Chapter 5, per Section 90.3. Similar proposals are submitted forArticles 502, 505, and 506 accordingly.



_______________________________________________________________________________________________Robert L. Seitz, Artech Engineering

Modify existing text.(1) General. In Class I, Division 1 locations, the wiring methods in (a) through (d)(e) shall be permitted.Add new text.(e) In industrial establishments with restricted public access, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation, and where the cable is not subject to physical damage,Shipboard Cable with braided metallic armor, that complies with the crush and impact requirements of Type MC-HLcable and is identified for such use with the marking, a separate equipment grounding conductor(s) in accordance with250.122, and terminated with fittings listed for the application. Braided armor Shipboard cable, shall be installed inaccordance with the provisions for TC-ER cable found in Article336.

Power cables of smaller conductor size, shielded pairs and triads and control cables with smallnumber of conductors are often connected to devices that must be removed or moved to permit maintenance activitiesto be performed, or for alterations to process piping. A cable that has greater flexibility than MC-HL would benefit thisactivity as the MC-HL cable cannot be moved out of the way of the work area sufficiently, so is generally subject todamage by the work effort that take place. A more flexible cable installed in small size wire basket tray can be movedfurther out of the way than can conduit or MC-HL installation.Line (pipe) mounted devices are subject to movement as pipes expand and contract with temperature changes and to

vibration caused by pumps and flow through the lines, so flexibility better than that provided by MC-HL cable or MI cableis needed. NEC 330.30(B) requires MC (thus MC-HL) cable to be supported within 12 inches of cable termination whencable has 4 or fewer conductors no larger than 10awg, which is often very difficult to provide support at line mounteddevices.While extra hard usage cord is permitted where flexible connection is required, the extra hard usage cord is notavailable in configurations with shielded pairs or triads or for controls connections to valves and other devices. So aflexible cable type is necessary that will satisfy the needs for instrumentation and control.

MC-HL has severe requirements imposed as it can be installed outside of cable tray, and as “not continuouslysupported”. If braided armor Shipboard cable is installed, generally, in cable tray and otherwise continuouslysupported, with up to 6 ft unsupported between cable tray and utilization equipment it would be well protected for itslength and exposed no more than would extra hard usage cord.Permitting braided armor Shipboard cable would not decrease the safety of Class I, Zone 1 electrical installations and

would enhance the maintainability, simply some installations, reduce risk of damage to cables during work around withinthe facilities where it is used.

Braided armor shipboard cable is not a wiring method that is permitted in Chapter 3. Thesubstantiation identifies cable of smaller conductor size, but the proposed language does not limit the conductor size.The wording of the proposal is confusing with respect to marking. The substantiation references Zone 1 locations, yetthe proposed wording is for Division 1 locations.Panel 14 recommends a multi-Panel task group, to include Panel 6 and/or Panel 7, to address the submitter's

concerns.





Where necessary to employ flexible connections, as at motor terminals, flexible fittings listed forthe location, or flexible cord in accordance with the provisions of 501.140 terminated with cord connectors listed for thelocation, shall be permitted to be installed.

Revise to differentiate cord that is installed with termination fittings from cord that is for temporary usewith an attachment plug. There have been several instances of confusion regarding these Code requirements.

See the panel action and panel statement on Proposal 14-11b. The proposed change does notimprove clarity, but the addition of the definition in accordance with Proposal 14-11b does address the submitter'sconcerns as expressed in the substantiation.

_______________________________________________________________________________________________14-35 Log #2565 NEC-P14

_______________________________________________________________________________________________Steven J. Blais, EGS Electrical Group

Also see companion proposal to Section 501.140(B)(4)Revise:

Where necessary to employ flexible connections, as at motor terminals, flexible fittings listedfor the location, or flexible cord in accordance with the provisions of 501.140. and terminated with cord connectors listedfor the location, shall be permitted.

During the 2011 ROC, CMP14 revised 501.140(B) to prescribe the methods of sealing in a Class I,Division 1 and a Class I, Division 2 location. In addition, the requirements for sealing in a Class I, Division 2 locationwhere the boxes, fittings, or enclosures are required to be explosion-proof where also added. The current rule inSection 501.10(A)(2) requires all fittings and boxes be terminated with cord connectors “listed for the location”. This ruledoes not permit the suitable method of 501.140(B) where a “listed” cord connector [not listed “for the location”] isinstalled into a seal fitting that is “listed for the location”. The revised wording in this proposal to 501.10(A)(2) wouldremove the contradiction.

Revise 501.10(A)(2) to read:Where necessary to employ flexible connections, as at motor terminals, flexible fittings listed

for the location, or flexible cord in accordance with the provisions of 501.140 terminated with cord connectors listed forthe location, shall be permitted.Also see companion proposal to Section 501.140(B)(4)

The panel's action meets the intent of this proposal and removes a potential ambiguity.

_______________________________________________________________________________________________14-36 Log #2470 NEC-P14


Revise text to read as follows:(5) Type MC, MV, TC or TC-ER cable, including installation in cable tray systems. The cable shall be terminated with

listed fittings.Add Type TC-ER cable. Other Extended Run cable constructions are currently permitted. Type

PLTC-ER, Type ITC-ER and Type TC-ER are all built to the same requirements.




Add new text to read as follows:(7) Fiber Optic cables of the types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall be permitted to

be installed in cable trays or any other raceway as stated in 501.10(B). Fiber Optic cables shall be sealed in accordancewith 501.15.

These proposals are a result of an ad-hoc task team consisting of members of CMP3, CMP14, andCMP16, along with industry representatives. Members of this task team included Rich Holub, Dave Wechsler, BobPotter, Bob Walsh, Harry Ohde, Terry Coleman, and Will Miller.Section 770.3(A) currently permits the use of Fiber Optic cables in hazardous (classified) locations if sealed in

accordance with Sections 501.15, 502.15, 505.16, and 506.16. Additionally, Section 770.113(H) permits the fiber opticcables of the types mentioned in cable trays. As such, and since cable trays are permitted for use in Division 2locations, the use of Fiber Optic cables of the types mentioned in hazardous (classified), Division 2, locations shouldalso be permitted. This proposal adds the requirements in Chapter 5 for correlation as Chapter 7 is not allowed tomodify Chapter 5, per Section 90.3. Similar proposals are submitted for Articles 502, 505, and 506 accordingly.

_______________________________________________________________________________________________14-37a Log #CP1403 NEC-P14


Revise 501.10(B)(2) as shown and add a new 501.10(B)(2)(6) to read as shown:501.10(B)(2) Flexible Connections. Where provision must be made for limited flexibility, one or more of the following

shall be permitted:(6) For elevator use, an identified elevator cable, type EO, ETP, or ETT, and as shown under the “use” column in Table

400.4 for “Hazardous (classified) locations” and terminated with listed fittings.

The word "limited" is deleted to remove ambiguity in the current language.Proposal 6-88 correctly identifies a situation where elevator cables are shown in Table 400.4 for "hazardous (classified)

locations", but the wiring method is not currently permitted in Chapter 5. The Panel agrees with the submitter'ssubstantiation in Proposal 6-88, however the Panel disagrees that it justifies removal of their use in hazardous(classified) locations. This proposal addresses the submitter's substantiation and corrects this correlation problem inChapter 5.



_______________________________________________________________________________________________Vince Baclawski, National Electrical Manufacturers Association (NEMA)

Revise text to read as follows:Where provision must be made for limited flexibility, one or more of the following shall be

permitted:(1) Listed flexible metal fittings.(2) Flexible metal conduit with listed fittings.(3) Interlocked armor Type MC cable with listed fittings.(3) (4) Liquidtight flexible metal conduit with listed fittings.(4) (5) Liquidtight flexible nonmetallic conduit with listed fittings.(5) (6) Flexible cord listed for extra-hard usage and terminated with listed fittings. A conductor for use as an equipment

grounding conductor shall be included in the flexible cord.The construction of MC Cable that includes interlocked armor is comparable to the flexible metal

conduit constructions and the twisted conductors under the armor make it suitable for use where flexibility is needed.Interlocked armor Type MC cable with listed fittings is equal to the other permitted wiring methods and provides forflexible connections. and Type MC cable is and has been permitted in Class 1, Div. 2 locations in section501.10(B)(1)(5).

_______________________________________________________________________________________________14-39 Log #2471 NEC-P14



Where provision must be made for limited flexibility, one or more of the following shallbepermitted to be installed:(1) Listed flexible metal fittings.(2) Flexible metal conduit with listed fittings.(3) Liquidtight flexible metal conduit with listed fittings.(4) Liquidtight flexible nonmetallic conduit with listed fittings.(5) Flexible power cord listed for extra-hard usage and terminated with listed fittings. A conductor for use as an

equipment grounding conductor shall be included in the flexible cord.Revise to differentiate power cord that is installed with termination fittings from cord that is for

temporary use with an attachment plug. There have been several instances of confusion regarding these Coderequirements.

The proposed changes do not improve clarity. The use of flexible cord is not limited to powerapplications.





(2) Flexible metal conduit (FMC) with listed fittings.Informational Note: See 501.30(B) for grounding requirements where flexible conduit (FMC) is used.

Flexible metal conduit (FMC) and liquidtight flexible metal conduitshall include an equipment bonding jumper of the wire type in compliance with 250.102.

"Flexible Metal Conduit" is also referred to as “FMC”Suggest that “(FMC)” be added to all references. This will make finding all references to "Flexible Metal Conduit"


See the panel action and statement on Proposal 14-29.

_______________________________________________________________________________________________14-41 Log #2853 NEC-P14



(4) Liquidtight flexible nonmetallic conduit (LFNC) with listed fittings

Informational Note: See 501.30(B) for grounding requirements where flexible conduit (LFNC) is used."Liquidtight Flexible Nonmetallic Conduit" is also referred to as “LFNC”

Suggest that “(LFNC)” be added to all references. This will make finding all references to "Liquidtight FlexibleNonmetallic Conduit" easier and more reliable.


_______________________________________________________________________________________________14-42 Log #2827 NEC-P14


Revise text to read as follows:(3) Liquidtight flexible metal conduit (LFMC) with listed fittings.

Informational Note: See 501.30(B) for grounding requirements where flexible conduit (LFMC) is used.Flexible metal conduit and liquidtight flexible metal conduit

(LFMC) shall include an equipment bonding jumper of the wire type in compliance with 250.102.

"Liquidtight Flexible Metal Conduit" is also referred to as “LFMC”Suggest that “(LFNC)” be added to all references. This will make finding all references to " Liquidtight Flexible Metal

Conduit " easier and more reliable.

See the panel action and proposal on Proposal 14-29.



_______________________________________________________________________________________________Kamalasanan Kunjukutty, Saudi Arabian Saipem Co. Ltd.

Add new paragraph:Installation of explosion proof cable gland for XLPE/PVC insulated unarmored cable in hazardous classified area

instead of conduit seal fittings. Conduit seal fittings shall not be used.Conduit seal fittings are not allowed in Saudi Arabia at Hazardous area and installation details are not

shown in any documents or NEC for unarmored XLPE and PLTC insulated cables exposed to atmosphere. Kindly findattached herewith suitable materials and drawings.Note: Supporting material is available for review at NFPA Headquarters.

The type of cable cited in this proposal is not permitted by the Code.

_______________________________________________________________________________________________14-44 Log #2350 NEC-P14

_______________________________________________________________________________________________Eric Kench, Kench Engineering Consultant

Revise text to read as follows:(4) Class I, Division I Boundary. In each conduit run leaving a Class I, Division I location., Thethe sealing fitting shall be

permitted on either side of the boundary of such location within 3.05 m (10 ft) of the boundary and shall be designed andinstalled so as to minimize the amount of gas or vapor within the Divsion I portion of the conduit from beingcommunicated to the conduit beyond the seal.

The first sentence ends abruptly with a period. This proposal will combine the first and secondsentences so that the rule would be more legible. The period has been replaced with a comma, also the word 'the'should not be capitalized.

The provision in question is one entry of a tabulated list.

_______________________________________________________________________________________________14-45 Log #1670 NEC-P14


Revise text to read as follows:Entering Enclosures. For connections to enclosures that are required to be explosion-proof, a conduit

seal shall be provided in accordance with 501.15(A)(1)(1) and (A)(3). All portions of the conduit run or nipple betweenthe seal and such enclosure shall comply with 501.10(A).

Remove archaic language.NEC style manual: 3.3.4 Word Clarity. Words and terms used in the shall be specific and clear in meaning, and

shall avoid jargon, trade terminology, industry-specific terms, or colloquial language that is difficult to understand.language shall be brief, clear, and emphatic. The following are examples of old-fashioned expressions and word usesthat shall not be permitted: "...and such...".




Revise:

................ Such seals shall not be required to be explosionproof but shall be identified for the purpose of minimizingpassage of gases to the rate permitted for seal fittings [200 cm3/hr (0.007 ft3/hr) of air at a pressure of 1500 pascals (6in. of water)] permitted under normal operating conditions and shall be accessible.

The current wording of this section does not define what the identification parameters are for“minimizing passage of gases under normal operating conditions”. The proposed language correlates with those forCables in a Class I, Division 2 location as well as the requirements for Sealing Fittings used in unclassified locations inaccordance with UL 514B, .

_______________________________________________________________________________________________14-47 Log #1964 NEC-P14

_______________________________________________________________________________________________Jonathan R. Althouse, Michigan State University

Add a new table containing 25 percent of the cross-sectional area of a seal and after the word sizein the third line add the words “as provided in Table 501.15(C)(6) and add the words “metric designator” before tradesize which would then be placed in parenthesis with the entire section as follows:

The cross-sectional area of the conductors permitted in a seal shall not exceed 25 percent of thecross-sectional area of a rigid metal conduit of the same metric designator (trade size), as provided in Table501.15(C)(6), unless it is specifically identified for a higher percentage of fill.

***INSERT TABLE NEC_L1964_501.15(C)(6)

There is no table containing 25% of the cross-sectional area of a rigid metal conduit to be used in thedetermination of the minimum trade size of seal required for an installation. The process of determining the minimumsize seal is a slow process and often not performed. When in doubt a seal of the next size larger is used with reducingbushings. This is costly and involves more connections which can lead to a failure in the system. Placing such a tablein this section will make the Code more user friendly.

There are products listed for conductor fills greater than 25 percent. The proposed Table wouldreduce the significance of the phrase "unless it is specifically identified for a higher percentage of fill".




The cross-sectional area of the conductors or optical fibers permitted in a sealshall not exceed 25 percent of the cross-sectional area of a rigid metal conduit of the same trade size unless it isspecifically identified for a higher percentage of fill.

These proposals are a result of an ad-hoc task team consisting of members of CMP3, CMP14, andCMP16, along with industry representatives. Members of this task team included Rich Holub, Dave Wechsler, BobPotter, Bob Walsh, Harry Ohde, Terry Coleman, and Will Miller.Section 770.3(A) currently acknowledges the use of Fiber Optic cables in hazardous (classified) locations if sealed in


Revise text to read as follows:The cross-sectional area of the conductors or optical fiber tubes (metallic or

nonmetallic) permitted in a seal shall not exceed 25 percent of the cross-sectional area of a rigid metal conduit of thesame trade size unless it is specifically identified for a higher percentage of fill.

The added text has been revised to indicate that the cross-sectional area of the optical fiber tube isto be used, not that of the optical fibers themselves.

_______________________________________________________________________________________________14-49 Log #2605 NEC-P14


Revise text to read as follows:Cables in conduit with a gas/vaportight continuous sheath

capable of transmitting gases or vapors through the cable core shall be sealed in the Division 1 location after removingthe jacket and any other coverings so that the sealing compound will surround each individual insulated conductor oroptical fiber tube and the outer jacket.






Revise text to read as follows:(1) Terminations. Cables entering enclosures that are required to be explosionproof shall be sealed at the point of

entrance. The sealing fitting shall comply with 501.15(B)(1) be explosionproof.501.15(B)(1) pertains to conduit seals and not cable seals. Referencing this NEC section would do

nothing but create confusion for the person reading it. There are cable connectors that are made for classified areas i.e.Appleton TMC/TMCX connectors.

Revise text to read as follows:(1) Terminations. Cables entering enclosures that are required to be explosionproof shall be sealed at the point of

entrance. The sealing fitting shall comply with 501.15(B)(1) or be explosionproof.Retaining the existing text, which the submitter had deleted, allows the existing practice of using

conduit seals or explosionproof cable sealing fittings (cable glands), as intended by the submitter.

_______________________________________________________________________________________________14-51 Log #2606 NEC-P14


Revise text to read as follows:( Cables entering enclosures that are required to be explosionproof shall be sealed at the point of

entrance. The sealing fitting shall comply with 501.15(B)(1). Multiconductor or optical multifiber cables with agas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in alisted fitting in the Division 2 location after removing the jacket and any other coverings so that the sealing compoundsurrounds each individual insulated conductor or optical fiber tube in such a manner as to minimize the passage ofgases and vapors. Multiconductor or optical multifiber cables in conduit shall be sealed as described in 501.15(D).



_______________________________________________________________________________________________14-52 Log #2690 NEC-P14


Revise text to read as follows:Where the authority having jurisdiction judges that there is a probability that liquid or condensed vapor may accumulate

within motors or generators, joints and conduit systems shall be arranged to minimize the entrance of liquid. If means toprevent accumulation or to permit periodic draining are judged necessary, such means shall be provided at the time ofmanufacture and shall be considered an integral part of the machine.

As 90.4 gives the AHJ authority to exercise judgement in application of the code, the struck-throughtext is redundant and unnecessary. The format of the revised text is consistent with that used in Section 501.20.




Revise text to read as follows:For connections to enclosures that are required to be flameproof or explosion-proof, a conduit seal

shall be provided in accordance with 505.16(B)(1) and (B)(2). All portions of the conduit run or nipple between the sealand such enclosure shall comply with 505.16(B).

Remove archaic language.NEC style manual: 3.3.4 Word Clarity. Words and terms used in the shall be specific and clear in meaning, and

shall avoid jargon, trade terminology, industry-specific terms, or colloquial language that is difficult to understand.language shall be brief, clear, and emphatic. The following are examples of old-fashioned expressions and word usesthat shall not be permitted: "...and such...".

_______________________________________________________________________________________________14-54 Log #1988 NEC-P14


Add new text to read as follows:(4) An add-on secondary seal marked “Secondary Seal” and rated for the pressure and temperature conditions that it

will be subjected to upon failure of the single process seal.Revise the Informative Note in this section as follows:Informative Note: For construction and testing requirements for process sealing for listed and marked “single seal”,or

“dual seal” or “secondary seal”equipment, requirements refer to ANSI/ISA-12.27.01, Requirements for Process SealingBetween Electrical Systems and Potentially Flammable or Combustible Process Fluids.

Requirements for an add-on secondary seal will be included in the next edition of ANSI/ISA-12.27.01.These seals have been examined and test to ensure that they are adequate and reliable process seals and should beallowed as an “additional means” in Section 501.17.Update the Informative Note to include “secondary seal”. Revise the title of ANSI/ISA-12.27.01.


will be subjected to upon failure of the single process seal.Revise the Informational Note in this section as follows:Informational Note: For construction and testing requirements for process sealing for listed and marked “single seal”,or

“dual seal” or “secondary seal”equipment, requirements refer to ANSI/ISA-12.27.01-2011, Requirements for ProcessSealing Between Electrical Systems and Potentially Flammable or Combustible Process Fluids.

The Panel has changed the word "informative" to "informational" and has added the publicationdate to the citation for ANSI/ISA-12.27.01, in accordance with 3.3.7.4 of the Regulations Governing Committee Projects.




Revise text to read as follows:Informational Note:Change ANSI/ISA-12.27.01-2003, Requirements for Process Sealing between Electrical Systems

and Potentially Flammable or Combustible Process Fluids to ANSI/ISA-12.27.01, Requirements for Process Sealingbetween Electrical Systems and Potentially Flammable or Combustible Process Fluids.


Revise the Informational Note to 501.17 to read: "Informational Note: For construction and testing requirements forprocess sealing for listed and marked “single seal” or “dual seal” requirements, refer to ANSI/ISA-12.27.01-2011,Requirements for Process Sealing Between Electrical Systems and Potentially Flammable or Combustible ProcessFluids."

Paragraph 3.3.7.4 of the Regulations Governing Committee Projects requires dated references toStandards. The current publication date for ISA 12.27.01 is 2011.

_______________________________________________________________________________________________14-56 Log #153 NEC-P14

_______________________________________________________________________________________________Gerald Newton, electrician2.com (National Electrical Resource Center)

Revise text to read as follows:Grounding and Bonding, Class I, Divisions 1 and 2. Wiring and equipment in Class I, Division 1 and 2 locations

shall be grounded as specified in Article 250 and in accordance with the requirements of 501.30(A) and (B).(A) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding

purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means ofbonding shall apply to all intervening raceways, fittings, boxes, enclosures, and so forth between Class I locations andthe point of grounding for service equipment or point of grounding of a separately derived system.Exception: The specific bonding means shall be required only to the nearest point where the grounded circuit

conductor and the grounding electrode are connected together on the line side of the building or structure disconnectingmeans as specified in 250.32(B), provided the branchcircuit overcurrent protection is located on the load side of thedisconnecting means.Informational Note: See 250.100 for additional bonding requirements in hazardous (classified) locations.(B) Types of Equipment Grounding Conductors. Flexible metal conduit and liquidtight flexible metal conduit shall

include an equipment bonding jumper of the wire type in compliance with 250.102.Exception: In Class I, Division 2 locations, the bonding jumper shall be permitted to be deleted where all of the

following conditions are met:(1) Listed liquidtight flexible metal conduit 1.8 m (6 ft) or less in length, with fittings listed for grounding, is used.(2) Overcurrent protection in the circuit is limited to 10 amperes or less.Grounding and Bonding. Grounding and bonding shall comply with Article 250.Informational Note: See 250.100 for additional bonding requirements in hazardous (classified) locations.

Duplication of text exists in five sections at 501.30, 502.30, 503.30, 505.25, and 506.25. This changewould move the requirements to Section 250.100 and eliminate duplication. The new text follows that already used insection 504.60.

Companion proposals have been submitted for sections 250.100, 502.30, 503.30, 505.25 and 506.25.

Grounding and bonding in hazardous (classified) locations is under the jurisdiction of Panel 14 notPanel 5. Panel 14 notes that some of the grounding and bonding methods permitted under Article 250.100 are notpermitted in Chapter 5.


Report on Proposals – June 2013 NFPA 70_______________________________________________________________________________________________14-56a Log #CP1409 NEC-P14


Remove the informational Note that references 250.100.This is a circular reference, as bonding and grounding are covered in the noted sections.

_______________________________________________________________________________________________14-57 Log #2692 NEC-P14


Revise text to read as follows:Flexible metal conduit and liquidtight flexible metal conduit shall include an equipment bonding jumper of the wire type

in compliance with in accordance with 250.102.Revise text for clarity. Additionally, Section 250.102 does not specify ‘wire type’.

Existing text is correct. The proposed text does not improve clarity.

_______________________________________________________________________________________________14-58 Log #671 NEC-P14

_______________________________________________________________________________________________Richard A. Janoski, Finleyville, PA

Revise text to read as follows:In a Class I Division 1 location, a multiwire branch circuit shall be permitted only if

the disconnect device opens all of the ungrounded circuit conductors simultaneously.As written, the current Code rule denies the use of any multiwire branch circuits. The exception allows

the use of them. Referencing the NEC Style manual, 3.1.4 Exceptions, "It is the responsibility of the Code-Making Panelto determine whether the principle can be expressed most effectively as a separate positive code rule or as anexception to a rule." 3.1.4 also references Annex A, the first sentence of which states, "Exceptions should be rewritteninto positive language, if positive language achieves clarity." I ask that CMP 14 consider that this rule would express itsidea clearer if it were written as a permissive code rule instead of an exception. A companion proposal has beensubmitted for Section 502.40, 505.21 and 506.21.

Section 501.40 has been deleted. See panel action on Proposal 14-59. Code-Making Panel 14notes that Chapter 2 applies to all installations except where superseded by provisions of a specific Code article.



_______________________________________________________________________________________________Jebediah J. Novak, Cedar Rapids Electrical JATC

Delete 501.40 and the exception.In a Class I, Division 1 location, a multiwire branch circuit shall not be permitted.

NEC Section 210.4(B) currently requires all multiwire branch-circuits to utilize a disconnecting meansthat will open all ungrounded conductors simultaneously. There is a lot of confusion by individuals in the field as to what501.40 and its exception intends of the user of the NEC. They feel this is requiring something different than what isrequired by 210.4(B), since it is being re-addressed here, and I do not think that is the case. Rather, it is language thatis redundant and is no longer necessary since Article 210 applies to all electrical installations, except as modified oramended by Chapter 5, 6, or 7.

_______________________________________________________________________________________________14-60 Log #3193 NEC-P14




_______________________________________________________________________________________________14-61 Log #872 NEC-P14

_______________________________________________________________________________________________Michael J. Johnston, National Electrical Contractors Association

Add a new last sentence to list item (5) as follows:(5) The receptacle carries a label warning against unplugging under load. The warning sign(s) or label(s) shall comply

with 110.21(B).This proposal is one of several coordinated companion proposals to provide consistency of danger,

caution, and warning sign or markings as required in the NEC. The proposed revision will correlate this warning markingrequirement with proposed 110.21(B) and the requirements in ANSI Z 535.4.

Section 110.21(B) does not exist.



_______________________________________________________________________________________________Robert L. Seitz, Artech Engineering / Rep. ISA

Revise text as shownTo facilitate replacements, process control instruments shall be permitted to be connected through

flexible cord, or instrument or control cable, attachment plug, and receptacle, provided all of the following conditionsapply:(1) A switch complying with 501.105(B)(1) is provided so that the attachment plug is not depended on to interrupt

current. If the circuit is non incendive the switch is not required.(2) The current does not exceed 3 amperes at 120 volts, nominal.(3) The power-supply cord does not exceed 900 mm (3 ft), is of a type listed for extra-hard usage or for hard usage if

protected by location, and is supplied through an attachment plug and receptacle of the locking and grounding type; orthe instrument or control cable is a Type TC cable or is an ITC cable permitted in 501.10(B) of this Code and is suppliedthrough an attachment plug and receptacle of the locking and grounding type.(4) Only necessary receptacles are provided.(5) The receptacle carries a label warning against unplugging under load and a tool is required to allow the receptacle

to be unplugged.

The use of flexible cords as permitted in 501.140 is primarily applicable to power supply connections topower utilization equipment. Process control instruments and devices require conductor configurations (eq shieldedpairs and triads), that are not available in extra hard usage cord. Process control instruments and devices are generallymore subject to removal and replacement than other equipments, so plug and receptacle connection provide means tomaintain electrical installations intact during work around activities in a facility. There currently is little guidance withinNFPA 70 on the use of plug and receptacle application that can be applied to the non-power applications.This proposal facilitates the ability for process instruments be properly replaced as this portion of Code originally

intended. The extra hard usage cord is not configured with the shielding and shield drain wires to permit proper wiringall the way to the field device or instrument. Permitting approved connectors to be installed on cables that are alreadypermitted as wiring methods should be a natural technological progression that will enhance the more sophisticatedautomation and control systems that process facilities are adopting.Improved connect ability can only enhance the safety of a facility as preterminated connectors will always have the

proper pin configurations when reconnected, the stripped ends of the conductors will not become frayed and theinsulation of the conductors will not be damaged.

Accept only the change to 501.105(B)(6)(1), but revise it to read:(1) A switch complying with 501.105(B)(1) is provided so that the attachment plug is not depended on to interrupt

current, unless the circuit is nonincendive field wiring, in which case the switch is not required.Reject all other portions of the submitter's proposal.

"Instrument or control cable" is not defined and, thus, is potentially unenforceable.The addition to 501.105(B)(6)(1) has been editorially revised for clarity and to narrow application to field wiring only.Fixed wiring methods (Types TC and ITC) are not intended to be terminated with an attachment plug. Attachment

plugs are only permitted to be used with flexible cords, as currently stated in 400.7(B).In (5), no substantiation was provided for the increase in the requirement.






_______________________________________________________________________________________________14-64 Log #3195 NEC-P14




_______________________________________________________________________________________________14-65 Log #2168 NEC-P14



Informational Note: See ASTM E659 - 78(2005) Standard Test Method for Autoignition Temperature of LiquidChemicals D2155-69, .

Standards update: ASTM D2155-66(1976) Method of Test for Autoignition Temperature of LiquidPetroleum Products (Withdrawn 1980) has been replaced by ASTM E659 - 78(2005) Standard Test Method forAutoignition Temperature of Liquid Chemicals.

The Informational Note in question has been deleted by Proposal 14-66a.




Add new text to read as follows:Informational Note No. 4: For reciprocating engine driven generators, compressors, and other loads installed in Class I

Division 2 locations, it is important to consider the risk of ignition of flammable materials associated with fuel, starting,compression, etc. that may be present due to inadvertent release or equipment malfunction by the engine ignitionsystem and controls. For further information on the requirements for ignition systems for reciprocating engines installedin Class I Division 2 hazardous (classified) locations, see ANSI/ISA-12.20.01,

.Currently there are numerous installations of reciprocating engine prime movers (engines) driving

generators, compressors, pumps, and various other loads installed in Class I Division 2 hazardous (classified) locations.These installations range from outdoor well ventilated areas within close proximity to production or process equipmentor in indoor locations that are adequately or inadequately ventilated handling flammable process, products, or fuel. Thecommonality between all these type installations is a natural gas fueled prime mover that utilizes a high voltage ignitionsystem.One specific example examined in detail: Ignition systems have been utilized on reciprocating engines driving natural

gas compressors in hazardous (classified) locations for many years. Operators of these compressor stations have onlyhad general guidance (NEC art 501, API RP 14F, local AHJ requirements) for proper source of ignition control for thesehazardous (classified) locations in the past. Conservative review of these general requirements led to the use ofshielded ignition systems where the primary high tension leads interconnecting the spark plugs for each power cylinderof the reciprocating engine to the ignition system were completely encased in grounded metallic sheathing materials toprevent any inadvertent arcs and sparks on the exterior of the ignition system that may lead to an ignition of a smallflammable gas leak or release associated with the gas compressor. These use of these shielded systems soon resultedin dielectric failures in the primary leads that resulted in ignition system miss-firing, miss-operations and engine damage.As these issues became more prevalent with compressor station operators, higher quality primary leads were developedbut were not able to resolve the high stresses associated with the shielded primary lead design. As most compressorstation buildings can be classified as Class I Division 2, the use of explosion-proof or flame-proof protection techniquesthat were utilized in the shielded ignition systems design may not be required. Recognizing this, ISA 12 organized aneffort to establish a fit for purpose performance standard that would employ Class I Division 2 protection techniquesutilizing non-shielded technology for ignition systems in these applications. The ANSI/ISA-12.20.01, GeneralRequirements for Electrical Ignition Systems for Internal Combustion Engines in Class I, Division 2 or Zone 2,Hazardous (Classified) Locations, provides specific details and performance test procedures for non-shielded ignitionsystems for use in Class I Division 2 installations.

Add new text to read as follows:Informational Note No. 4: For reciprocating engine driven generators, compressors, and other equipment installed in

Class I Division 2 locations, it is important to consider the risk of ignition of flammable materials associated with fuel,starting, compression, etc. that may be present due to inadvertent release or equipment malfunction by the engineignition system and controls. For further information on the requirements for ignition systems for reciprocating enginesinstalled in Class I Division 2 hazardous (classified) locations, see ANSI/ISA-12.20.01-2009,

.The panel has editorially revised the proposed text by changing the word "loads" in the first

sentence to "equipment" and by adding the publication date of 2009 to ANSI/ISA-12.20.01, in accordance with 3.3.7.4 ofthe Regulations Governing Committee Projects.Code-Making Panel 14 notes that the print line should read "501.125(B), FPN 4".




Delete the Informational Note under 501.125(A) entirely.The Note does not provide useful information in this location.

_______________________________________________________________________________________________14-67 Log #3196 NEC-P14




_______________________________________________________________________________________________14-68 Log #3197 NEC-P14






_______________________________________________________________________________________________Frederick Bried, Spring, TX

Revise text to read as follows:For further information on the application of electric motors in Class I, Division 2 hazardous (classified) locations, see

IEEE Std. 1349-20011, IEEE Guide for the Application of Electric Motors in Class I, Division 2 and Class I, Zone 2Hazardous (Classified) Locations.

IEEE 1349-2001, which originally addressed the application of electric motors in Class I, Division 2hazardous (classified) locations, has been revised, updated and expanded to include the application of electric motors inClass I, Zone 2 hazardous (classified) locations.

_______________________________________________________________________________________________14-70 Log #1109 NEC-P14


Add new text to read as follows:For further information on the application of electric motors in Class I, Zone 2 hazardous (classified) locations, see

IEEE Std. 1349-20011,


_______________________________________________________________________________________________14-71 Log #3198 NEC-P14







Revise text to read as follows:Portable lighting equipment shall comply with 501.130(A)(1).

Current text states that something is permitted but doesn’t state what that is. Since the exception is tothe requirement that portable luminaires comply with the Division 1 requirements, the intent of the exception is to permitcompliance with the Division 2 requirements as stated in 501.130(B)(1).

There is no substantiation to support the reduction of the protection level of portable luminairesfrom Division 1 to Division 2.

_______________________________________________________________________________________________14-73 Log #3199 NEC-P14




_______________________________________________________________________________________________14-74 Log #3200 NEC-P14








Flexible power cords shall be permitted:For connection between portable lighting equipment or other portable utilization equipment and the fixed portion of

their supply circuit. The flexible power cord is attached to the utilization equipment with a cord connector listed for theexplosion protection technique of the equipment wiring compartment entry. An attachment plug in accordance with501.140(B)(4) shall be employed.

Revise to make clear that 501.140(A)(1) covers power cords that attach to the utilization equipmentwith a cord connector and have an attachment plug for connection to premises wiring. There have been severalinstances of confusion regarding these Code requirements.


Flexible cords shall be permitted:For connection between portable lighting equipment or other portable utilization equipment and the fixed portion of

their supply circuit. The flexible cord shall be attached to the utilization equipment with a cord connector listed for theprotection technique of the equipment wiring compartment. An attachment plug in accordance with 501.140(B)(4) shallbe employed.

The Panel has deleted the words "power", "explosion", and "entry" and reworded for clarity.

_______________________________________________________________________________________________14-76 Log #2567 NEC-P14


Also see companion proposal to Section 501.10(A)(2)Revise:(4) In Division 1 locations or in Division 2 locations where the boxes, fittings, or enclosures are required to be

explosionproof, the cord shall be terminated with a cord connector or attachment plug listed for the location or a listedcord connector installed with a seal listed for the location. In Division 2 locations where explosionproof equipment is notrequired, the cord shall be terminated with a listed cord connector or listed attachment plug.

During the 2011 ROC, CMP14 revised 501.140(B) to prescribe the methods of sealing in a Class I,Division 1 and a Class I, Division 2 location. In addition, the requirements for sealing in a Class I, Division 2 locationwhere the boxes, fittings, or enclosures are required to be explosion-proof where also clarified. A companion proposalhas been submitted to clarify in Section 501.10(A)(2) that the cord connector does not always have to be “listed for thelocation”, but can be a listed cord connector and installed with a seal that is “listed for the location”. This isaccomplished by reference to the installation requirements in 501.140(B). What 501.140(B)(4) is currently missing is therequirement that the when the cord connector is installed “with” a seal that is “listed for the location”, this cord connectormust be listed (ANSI/UL 514B for unclassified Conduit, Tubing, and Cable Fittings).





Premises wiring receptacles and the utilization equipment attachment plugs shall be of the type providing forconnection to the equipment grounding conductor of a flexible cord and shall be identified for the location.

Revise to make clear that the receptacle is part of the premises wiring and that the attachment plug ispart of the utilization equipment. There have been several instances of confusion regarding these Code requirementswith respect to cord being supplied with a plug for connection to receptacle on the utilization equipment. Such aconstruction present and arcing hazard and the potential for exposed live parts within the classified location.


(A) Receptacles. Receptacles shall be part of the premises wiring, except as permitted by 501.140(A)(5).(B) Attachment Plugs. Attachment plugs shall be of the type providing for connection to the equipment grounding

conductor of a flexible cord and shall be identified for the location.

The revised wording meets the intent of the submitter and provides more clarity.




Add a new 501.155 to address the issue of Class I equipment involving optical radiation inexplosive gas atmospheres. This item is separate from the existing 500.9(F) regarding Optical fiber cables because,while Optical fiber cables are equipment using optical radiation, the intent of 500.9(F) is to address the issue of cablescontaining conductors that are capable of carrying current in Class I, II and III areas, not optical radiation.

The risk of ignition from optical radiation, both inside and outsideoptical equipment, shall be considered for all electrical parts and circuits except for non-array indicator LEDs used toshow equipment status, for luminaires with divergent light sources and for optical radiation sources for Zone 2applications which comply with Class I limits for light emitting (e.g. laser) products. This includes equipment, which itselfis located outside the hazardous (classified) location, but its emitted optical radiation enters such locations.Informational Note: For additional information on types of protection that can be applied to minimize the risk of ignition

in hazardous (classified) locations from optical radiation in the wavelength range from 380 nm to 10 ìm, seeANSI/ISA–TR12.21.01,

● The 2011 edition of the NEC does not address the potential for optical radiation to cause ignition inan explosive atmosphere. It does address optical fiber cables, but not from the perspective of the potential to causeignition.● ANSI/ISA-TR12.21.01, , contain published

US national requirements that address the potential risk of ignition associated with optical radiation in Division classifiedareas.● This ANSI/ISA standard is aligned with harmonized with ANSI/ISA-60079-28 (12.21.02),

, and IEC/EN 60079-28:2006,, for Zone

classified areas.● ANSI/ISA-TR12.21.01 defines three types of protection that can be applied to address the potential for optical

radiation to cause ignition in potentially explosive atmospheres. These types of protection are: 1) inherently safe opticalradiation; 2) protected optical radiation; and 3) optical system with interlock.● This proposal introduces these types of protection, along with the general term ‘optical radiation’ and one of the

more common applications of optical radiation in explosive atmospheres, ‘protected optical fiber cable’.● Additional proposals are being submitted to introduce related, supporting text under 500.2 and 500.7.● It should be noted that the sources of the optical radiation are electrical equipment. Therefore this proposal is


See Panel Action and Panel Statement on Proposal 14-20.





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

(2) Rigid metal conduit, intermediate metal conduit (IMC), electrical metallic tubing, dusttight wireways.(7) In industrial establishments with restricted public access where the conditions of maintenance and supervision

ensure that only qualified persons service the installation and where metallic conduit (IMC) does not provide sufficientcorrosion resistance, reinforced thermosetting resin conduit (RTRC) factory elbows, and associated fittings, all markedwith suffix -XW, and Schedule 80 PVC conduit, factory elbows and associated fittings shall be permitted.

Pendant luminaires shall be suspended by threaded rigid metal conduit stems, by threadedsteel intermediate metal conduit (IMC) stems, by chains with approved fittings, or by other approved means. For rigidstems longer than 300 mm (12 in.), permanent and effective bracing against lateral displacement shall be provided at alevel not more than 300 mm (12 in.) above the lower end of the stem, or flexibility in the form of a fitting or a flexibleconnector listed for the location shall be provided not more than 300 mm (12 in.) from the point of attachment to thesupporting box or fitting. Threaded joints shall be provided with set screws or other effective means to preventloosening. Where wiring between an outlet box or fitting and a pendant luminaire is not enclosed in conduit, flexible cordlisted for hard usage shall be permitted to be used in accordance with 502.10(A)(2)(5). Flexible cord shall not serve asthe supporting means for a luminaire.

Pendant luminaires shall be suspended by threaded rigid metal conduit stems, by threadedsteel intermediate metal conduit (IMC) stems, by chains with approved fittings, or by other approved means. For rigidstems longer than 300 mm (12 in.), permanent and effective bracing against lateral displacement shall be provided at alevel not more than 300 mm (12 in.) above the lower end of the stem, or flexibility in the form of an identified fitting or aflexible connector shall be provided not more than 300 mm (12 in.) from the point of attachment to the supporting box orfitting. Where wiring between an outlet box or fitting and a pendant luminaire is not enclosed in conduit, flexible cordlisted for hard usage shall be permitted if terminated with a listed cord connector that maintains the protection technique.Flexible cord shall not serve as the supporting means for a luminaire..



See the panel action and statement Proposal 14-29.




Revise text to read as follows:Wiring methods shall comply with 502.10(A) or (B).

In Class II, Division 1 locations, the wiring methods in (1) through (4) 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 and supported in a

manner to avoid tensile stress at the termination fittings.(3) In industrial establishments with limited public access, where the conditions of maintenance and supervision ensure

that only qualified persons service the installation, Type MC-HL cable, listed for use in Class II, Division 1 locations, witha gas/vaportight continuous corrugated metallic sheath, an overall jacket of suitable polymeric material, a separateequipment grounding conductor(s) in accordance with 250.122, and provided with termination fittings listed for theapplication, shall be permitted.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .(4) Fittings and boxes shall be provided with threaded bosses for connection to conduit or cable terminations and shall

be dusttight. Fittings and boxes in which taps, joints, or terminal connections are made, or that are used in Group Elocations, shall be identified for Class II locations.

Where necessary to employ flexible connections, one or more of the following shall also bepermitted:(1) Dusttight flexible connectors(2) Liquidtight flexible metal conduit with listed fittings(3) Liquidtight flexible nonmetallic conduit with listed fittings(4) Interlocked armor Type MC cable having an overall jacket of suitable polymeric material and provided with

termination fittings listed for Class II, Division 1 locations.(5) Flexible cord listed for extra-hard usage and terminated with listed dusttight fittings. Where flexible cords are used,

they shall comply with 502.140.Informational Note: See 502.30(B) for grounding requirements where flexible conduit is used.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .

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.(4) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, including installation 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, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer,

with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring methodemployed.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .(7) In industrial establishments with restricted public access where the conditions of maintenance and supervision

ensure that only qualified persons service the installation and where metallic conduit does not provide sufficientcorrosion resistance, reinforced thermosetting resin conduit (RTRC) factory elbows, and associated fittings, all markedwith suffix -XW, and Schedule 80 PVC conduit, factory elbows and associated fittings shall be permitted.



Report on Proposals – June 2013 NFPA 70

Revise 502.10 to read:502.10 Wiring Methods. Wiring methods shall comply with 502.10(A) or (B).(A) Class II, Division 1.

(1) General. In Class II, Division 1 locations, the wiring methods in (1) through (34) 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 and supported in a

manner to avoid tensile stress at the termination fittings.(3) In industrial establishments with limited public access, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation, Type MC-HL cable, listed for use in Class II, Division 1locations, with a gas/vaportight continuous corrugated metallic sheath, an overall jacket of suitable polymeric material, aseparate equipment grounding conductor(s) in accordance with 250.122, and provided with termination fittings listed forthe application location, shall be permitted.(4) Fittings and boxes shall be provided with threaded bosses for connection to conduit or cable terminations and shall

be dusttight. Fittings and boxes in which taps, joints, or terminal connections are made, or that are used in Group Elocations, shall be identified for Class II locations.

(2) Flexible Connections. Where necessary to employ flexible connections, one or more of the following shallalso be permitted:(1) Dusttight flexible connectors(2) Liquidtight flexible metal conduit with listed fittings(3) Liquidtight flexible nonmetallic conduit with listed fittings(4) Interlocked armor Type MC cable having an overall jacket of suitable polymeric material and provided with

termination fittings listed for Class II, Division 1 locations.(5) Flexible cord listed for extra-hard usage and terminated with listed dusttight fittings. Where flexible cords are used,

they shall comply with 502.140.Informational Note: See 502.30(B) for grounding requirements where flexible conduit is used.

(3) Boxes and Fittings. Fittings Boxes and boxes fittings shall be provided with threaded bosses for connectionto conduit or cable terminations and shall be dusttight. Boxes Fittings and fittings boxes in which taps, joints, or terminalconnections are made, or that are used in Group E locations, shall be identified for Class II locations.Informational Note: For entry into enclosures required to be dust-ignitionproof, see further information on construction,

testing and marking of cables, dust-ignitionproof cable fittings, and dust-ignitionproof cord connectors in ANSI/UL2225-2011, Cables and Cable-Fittings for Use in Hazardous (Classified) Locations.(B) Class II, Division 2.

(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.(4) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, including installation in

cable tray systems. The cable shall be terminated with listed fittings.(5) Type ITC and Type ITC-ER cable a permitted in 727.4 and terminated with listed fittings.(6) Type MC, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer,

with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring methodemployed.Exception to (6): Type MC cable listed for use in Class II, Division 1 locations shall be permitted to be installed without

the spacings required by (6).(7) In industrial establishments with restricted public access where the conditions of maintenance and supervision

ensure that only qualified persons service the installation and where metallic conduit does not provide sufficientcorrosion resistance, reinforced thermosetting resin conduit (RTRC) factory elbows, and associated fittings, all markedwith suffix -XW, and Schedule 80 PVC conduit, factory elbows and associated fittings shall be permitted.

(2) Flexible Connections. Where provision must be made for flexibility, 502.10(A)(2) shall apply.(3) Nonincendive Field Wiring. Nonincendive field wiring shall be permitted using any of the wiring methods

permitted for unclassified locations. Nonincendive field wiring systems shall be installed in accordance with the controldrawing(s). Simple apparatus, not shown on the control drawing, shall be permitted in a nonincendive field wiring circuit,provided the simple apparatus does not interconnect the nonincendive field wiring circuit to any other circuit.Informational Note: Simple apparatus is defined in 504.2.Separate nonincendive field wiring circuits shall be installed in accordance with one of the following:(1) In separate cables


Report on Proposals – June 2013 NFPA 70(2) In multiconductor cables where the conductors of each circuit are within a grounded metal shield(3) In multiconductor cables or in raceways where the conductors of each circuit have insulation with a minimum

thickness of 0.25 mm (0.01 in.)(4) Boxes and Fittings. All boxes and fittings shall be dusttight.

The panel action meets the intent of the proposal.The date of the published standard was added in accordance with 3.3.7.4 of the Regulations Governing Committee

Projects.The word “application” was revised to “location” to better clarify that these fittings are required to be listed for Class II,

Division 1 locations. 502.10(A)(1)(4) was relocated to a new separate section (502.10(A)(3)) to separately addressBoxes and Fittings which correlates with the corresponding sections of Article 501.The proposed Informational Note to add to 502.10(A)(2) was rejected as the proposed reference standard does not

cover the requirements for “dusttight” ratings. Dusttight ratings for fittings are covered in the ordinary location standards.The proposed Informational Note was revised and added to the newly created section for Boxes and Fittings for ClassII, Division 1 locations. As this section covers both the requirements for “dusttight” fittings and fittings that are requiredto be listed for the location, the proposed Informational Note was revised to clarify when the reference to UL 2225 isapplicable.

_______________________________________________________________________________________________14-81 Log #2795 NEC-P14



Informational Note: See 502.30(B) for grounding requirements where flexible conduit (FMC) is used."Flexible Metal Conduit" is also referred to as “FMC”

Suggest that “(FMC)” be added to all references. This will make finding all references to "Flexible Metal Conduit"easier and more reliable.






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

(2) Rigid metal conduit (RMC), intermediate metal conduit, electrical metallic tubing, dusttight wireways.(7) In industrial establishments with restricted public access where the conditions of maintenance and supervision

ensure that only qualified persons service the installation and where metallic conduit (RMC) does not provide sufficientcorrosion resistance, reinforced thermosetting resin conduit (RTRC) factory elbows, and associated fittings, all markedwith suffix -XW, and Schedule 80 PVC conduit, factory elbows and associated fittings shall be permitted.

Pendant luminaires shall be suspended by threaded rigid metal conduit (RMC) stems, bythreaded steel intermediate metal conduit stems, by chains with approved fittings, or by other approved means. For rigidstems longer than 300 mm (12 in.), permanent and effective bracing against lateral displacement shall be provided at alevel not more than 300 mm (12 in.) above the lower end of the stem, or flexibility in the form of a fitting or a flexibleconnector listed for the location shall be provided not more than 300 mm (12 in.) from the point of attachment to thesupporting box or fitting. Threaded joints shall be provided with set screws or other effective means to preventloosening. Where wiring between an outlet box or fitting and a pendant luminaire is not enclosed in conduit, flexible cordlisted for hard usage shall be permitted to be used in accordance with 502.10(A)(2)(5). Flexible cord shall not serve asthe supporting means for a luminaire.

Pendant luminaires shall be suspended by threaded rigid metal conduit (RMC) stems, bythreaded steel intermediate metal conduit stems, by chains with approved fittings, or by other approved means. For rigidstems longer than 300 mm (12 in.), permanent and effective bracing against lateral displacement shall be provided at alevel not more than 300 mm (12 in.) above the lower end of the stem, or flexibility in the form of an identified fitting or aflexible connector shall be provided not more than 300 mm (12 in.) from the point of attachment to the supporting box orfitting. Where wiring between an outlet box or fitting and a pendant luminaire is not enclosed in conduit, flexible cordlisted for hard usage shall be permitted if terminated with a listed cord connector that maintains the protection technique.Flexible cord shall not serve as the supporting means for a luminaire.


and more reliable.

See the panel action and statement Proposal 14-29.








_______________________________________________________________________________________________14-84 Log #189 NEC-P14


Revise text to read as follows:Flexible cord listed for extra-hard usage and terminated with listed dusttight fittings connectors.

Where flexible cords are used, they shall comply with 502.140.Flexible cord is terminated using connectors not fittings. Section 502.140(4) uses connectors in three

places instead of fittings. Ref: 502.140(4) In Division 1 locations, the cord shall be terminated with a cord connectorlisted for the location or a listed cord connector installed with a seal listed for the location. In Division 2 locations, thecord shall be terminated with a listed dusttight cord connector.

Revise text to read as follows:Flexible cord listed for extra-hard usage and terminated with listed dusttight fittings cord connectors.

Where flexible cords are used, they shall comply with 502.140.Text has been revised to use the Panel's defined terminology.

_______________________________________________________________________________________________14-85 Log #2828 NEC-P14



(2) Liquidtight flexible metal conduit (LFMC) with listed fittings

Informational Note: See 502.30(B) for grounding requirements where flexible conduit (LFMC) is used.Liquidtight flexible metal conduit (LFMC) shall include an

equipment bonding jumper of the wire type in compliance with 250.102.












_______________________________________________________________________________________________14-87 Log #1815 NEC-P14


Revise text to read as follows:(2) Rigid metal conduit, intermediate metal conduit, electrical metallic tubing (EMT), dusttight wireways.

"electrical metallic tubing" is also referred to as “EMT”Suggest that "EMT" be added to all references. This will make finding all references to "electrical metallic tubing" easier

and more reliable.[The following files are related: 100_EMT, 225_EMT, 230_EMT, 250_EMT, 300_EMT, 334_EMT, 374_EMT, 392_EMT,

398_EMT, 424_EMT, 426_EMT, 427_EMT, 430_EMT, 502_EMT, 503_EMT, 506_EMT, 517_EMT, 520_EMT, 550_EMT,551_EMT, 552_EMT, 600_EMT, 610_EMT, 620_EMT, 645_EMT, 680_EMT, 695_EMT, 725_EMT, 760_EMT]


_______________________________________________________________________________________________14-88 Log #2610 NEC-P14


Add new text to read as follows:(8) Fiber Optic cables of the types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG,OFN, and OFC shall be permitted to

be installed in cable trays or any other raceway as stated in 502.10(B). Fiber Optic cables shall be sealed in accordancewith 502.15.

These proposals are a result of an ad-hoc task team consisting of members of CMP3, CMP14, andCMP16, along with industry representatives. Members of this task team included Rich Holub, Dave Wechsler, BobPotter, Bob Walsh, Harry Ohde, Terry Coleman, and Will Miller.Section 770.3(A) currently permits the use of Fiber Optic cables in hazardous (classified) locations if sealed in

accordance with Sections 501.15, 502.15, 505.16, and 506.16. Additionally, Section 770.113(H) permits the fiber opticcables of the types mentioned in cable trays. As such, and since cable trays are permitted for use in Division 2 locationsin accordance with Article 725, the use of Fiber Optic cables of the types mentioned in hazardous (classified), Division 2,locations should also be permitted. This proposal adds the requirements in Chapter 5 for correlation as Chapter 7 is notallowed to modify Chapter 5, per Section 90.3. Similar proposals are submitted for Articles 501, 505, and 506accordingly.




Insert a new 502.10(B)(2)(6) to read:(6) For elevator use, an identified elevator cable, type EO, ETP, or ETT, and as shown under the “use” column in Table

400.4 for “Hazardous (classified) locations” and terminated with listed dusttight fittings.

Proposal 6-88 correctly identifies a situation where elevator cables are shown in Table 400.4 for“hazardous (classified) locations” but the wiring method is not currently permitted in Chapter 5. The Panel agrees withthe submitter's substantiation in Proposal 6-88, however the Panel disagrees that it justifies removal of their use inhazardous (classified) locations. This proposal addresses the submitter’s substantiation and corrects this correlationproblem in Chapter 5.

_______________________________________________________________________________________________14-89 Log #154 NEC-P14


Revise text to read as follows:Grounding and Bonding, Class II, Divisions 1 and 2. Wiring and equipment in Class II, Division 1 and 2

locations shall be grounded as specified in Article 250 andin accordance with the requirements of 502.30(A) and (B).(A) Bonding. The locknut-bushing and double-locknut types of contact shall not be depended on for bonding purposes,

but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means of bondingshall apply to all intervening raceways, fittings, boxes, enclosures, and so forth, between Class II locationsand the point of grounding for service equipment or point of grounding of a separately derived system.Exception: The specific bonding means shall only be required to the nearest point where the grounded circuit

conductor and the grounding electrode conductor are connected together on the line side of the building or structuredisconnecting means as specified in 250.32(B) if the branch-circuit overcurrent protection is located on the load side ofthe disconnecting means.

See 250.100 for additional bonding requirements in hazardous (classified) locations.(B) Types of Equipment Grounding Conductors. Liquidtight flexible metal conduit shall include an equipment bonding

jumper of the wire type in compliance with 250.102.Exception: In Class II, Division 2 locations, the bonding jumper shall be permitted to be deleted where all of the

following conditions are met:(1) Listed liquidtight flexible metal conduit 1.8 m (6 ft) or less in length, with fittings listed for grounding, is used.(2) Overcurrent protection in the circuit is limited to 10 amperes or less.(3) The load is not a power utilization load.Grounding and Bonding. Grounding and bonding shall comply with Article 250.Informational Note: See 250.100 for additional bonding requirements in hazardous (classified) locations.



See the panel action and panel statement on Proposal 14-56.




Revise text to read as follows:Liquidtight flexible metal conduit shall include an equipment bonding jumper of the wire type in compliance with in

accordance with 250.102.Revise text for clarity. Additionally, Section 250.102 does not specify ‘wire type’.


_______________________________________________________________________________________________14-91 Log #672 NEC-P14


Revise text to read as follows:502.40 Multiwire Branch Circuits. In a Class II Division 1 location, a multiwire branch circuit shall be permitted only if

the disconnect device opens all of the ungrounded circuit conductors simultaneously.As written, the current Code rule denies the use of any multiwire branch circuits. The exception allows

the use of them. Referencing the NEC Style manual, 3.1.4 Exceptions, "It is the responsibility of the Code-Making Panelto determine whether the principle can be expressed most effectively as a separate positive code rule or as anexception to a rule." 3.1.4 also references Annex A, the first sentence of which states, "Exceptions should be rewritteninto positive language, if positive language achieves clarity." I ask that CMP 14 consider that this rule would express itsidea clearer if it were written as a permissive code rule instead of an exception. A companion proposal has beensubmitted for Section 501.40, 505.21 and 506.21.

Section 502.40 has been removed from the code. See panel action on Proposal 14-92.

_______________________________________________________________________________________________14-92 Log #2706 NEC-P14

_______________________________________________________________________________________________Jebediah J. Novak, Cedar Rapids Electrical JATC

Delete 502.40 and the exception.In a Class II, Division 1 location, a multiwire branch circuit shall not be permitted.

NEC Section 210.4(B) currently requires all multiwire branch-circuits to utilize a disconnecting meansthat will open all ungrounded conductors simultaneously. There is a lot of confusion by individuals in the field as to what502.40 and its exception intends of the user of the NEC. They feel this is requiring something different than what isrequired by 210.4(B), since it is being re-addressed here, and I do not think that is the case. Rather, it is language thatis redundant and is no longer necessary since Article 210 applies to all electrical installations, except as modified oramended by Chapter 5, 6, or 7.



_______________________________________________________________________________________________James T. Dollard, Jr., IBEW Local Union 98

Replace 600V with 1000V.This proposal is the work of the “High Voltage Task Group” appointed by the Technical Correlating

Committee. The task group consisted of the following members: Alan Peterson, Paul Barnhart, Lanny Floyd, AlanManche, Donny Cook, Vince Saporita, Roger McDaniel, Stan Folz, Eddie Guidry, Tom Adams, Jim Rogers and JimDollard.The Task Group identified the demand for increasing voltage levels used in wind generation and photovoltaic systems

as an area for consideration to enhance existing NEC requirements to address these new common voltage levels. Thetask group recognized that general requirements in Chapters 1 through 4 need to be modified before identifying andgenerating proposals to articles such as 690 specific for PV systems. These systems have moved above 600V and arereaching 1000V due to standard configurations and increases in efficiency and performance. The committee reviewedChapters 1 through 8 and identified areas where the task group agreed that the increase in voltage was of minimal or noimpact to the system installation. Additionally, there were requirements that would have had a serious impact and thetask group chose not to submit a proposal for changing the voltage. See table (supporting material) that summarizes allsections considered by the TG.Note: Supporting material is available for review at NFPA Headquarters.

There is no evidence provided that dry-type transformers, of voltages between 600 and 1000 volts,are currently available so that their suitability for this application can be assessed

_______________________________________________________________________________________________14-94 Log #2349 NEC-P14


Revise text to read as follows:(2) Totally enclosed pipe-ventilated, meeting temperature limitations in 502.5.

NEC 502.5 does not contain any temperature limitations. This proposal deletes the text that referencesthe section and eliminates the confusion.



_______________________________________________________________________________________________Marcus R. Sampson, Lysistrata Electric

Revise text to read as follows:Revise text to read as follows:

In Class II, Division 1 locations, luminaires for fixed and portable lighting shall comply with502.130(A)(1) through (A)(4).

Each luminaire shall be identified for the location and shall be clearly marked to indicate themaximum wattage of the lamp for which it is designed.

The title of the section is “luminaires” so the title of the subsection could be a little more specific toassist the user in finding and complying with this marking. Requirement for luminaires.


In Class II, Division 1 locations, luminaires for fixed and portable lighting shall comply with502.130(A)(1) through (A)(4).

Each luminaire shall be identified for the location and shall be clearly marked to indicate thetype and maximum wattage of the lamp for which it is designed.

The type of lamp also needs to be identified. The Panel notes that the reference to 502.130(A)(1)through (A)(4) are already part of 502.130(A).





Flexible power cords used in Class II locations shall comply with all of the following:(1) For connection between portable lighting equipment or other portable utilization equipment and the fixed portion of

their supply circuit. The flexible power cord is attached to the utilization equipment with a cord connector listed for theexplosion protection technique of the equipment wiring compartment entry. An attachment plug in accordance with502.145 shall be employed.(2) Where flexible power cord is permitted by 502.10(A)(2) for fixed and mobile electrical utilization equipment, and the

flexible cord is protected by location or by a suitable guard from damage and only in an industrial establishment whereconditions of maintenance and engineering supervision ensure that only qualified persons install and service theinstallation.(3) For electric submersible pumps with means for removal without entering the wet-pit. The extension of the flexible

cord within a suitable raceway between the wet-pit and the power source shall be permitted.(4) For electric mixers intended for travel into and out of open-type mixing tanks or vats.(5) For temporary portable assemblies consisting of receptacles, switches, and other devices that are not considered

portable utilization equipment but are individually listed for the location.Where flexible power cords are used, the cords shall comply with all of 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 complying with 400.23(3) Be supported by clamps or by other suitable means in such a manner that there will be no tension on the terminal

connections(4) In Division 1 locations, the cord shall be terminated with a cord connector listed for the location or a listed cord

connector installed with a seal listed for the location. In Division 2 locations, the cord shall be terminated with a listeddusttight cord connector fitting.(5) Be of continuous length. Where 502.140(A)(5) is applied, cords shall be of continuous length from the power source

to the temporary portable assembly and from the temporary portable assembly to the utilization equipment.Revise to make the permitted use and installation requirements mirror 501.140 as appropriate,

including make clear that 501.140(A)(1) covers power cords that attach to the utilization equipment with a cordconnector and have an attachment plug for connection to premises wiring. There have been several instances ofconfusion regarding these Code requirements.


Flexible cords used in Class II locations shall comply with all of the following:(1) For connection between portable lighting equipment or other portable utilization equipment and the fixed portion of

their supply circuit. The flexible cord is attached to the utilization equipment with a cord connector listed for theprotection technique of the equipment wiring compartment. An attachment plug in accordance with 502.145 shall beemployed.(2) Where flexible cord is permitted by 502.10(A)(2) for fixed and mobile electrical utilization equipment, and the flexible

cord is protected by location or by a suitable guard from damage and only in an industrial establishment whereconditions of maintenance and engineering supervision ensure that only qualified persons install and service theinstallation.(3) For electric submersible pumps with means for removal without entering the wet-pit. The extension of the flexible

cord within a suitable raceway between the wet-pit and the power source shall be permitted.(4) For electric mixers intended for travel into and out of open-type mixing tanks or vats.(5) For temporary portable assemblies consisting of receptacles, switches, and other devices that are not considered

portable utilization equipment but are individually listed for the location.Where flexible cords are used, the cords shall comply with all of the following:

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


Report on Proposals – June 2013 NFPA 70(2) Contain, in addition to the conductors of the circuit, an equipment grounding conductor complying with 400.23(3) Be supported by clamps or by other suitable means in such a manner that there will be no tension on the terminal

connections(4) In Division 1 locations, the cord shall be terminated with a cord connector listed for the location or a listed cord

connector installed with a seal listed for the location. In Division 2 locations, the cord shall be terminated with a listeddusttight cord connector.(5) Be of continuous length. Where 502.140(A)(5) is applied, cords shall be of continuous length from the power source

to the temporary portable assembly and from the temporary portable assembly to the utilization equipment.The proposed text has been revised by:

deleting the word "power" in front of "cords" wherever it appears; deleting the words "explosion" and "entry" in502.140(A)(1); deleting the word "fitting" in 502.140(B)(4).These deletions are made to effect correlation with other amendments.

_______________________________________________________________________________________________14-97 Log #2476 NEC-P14



In Class II, Division 1 locations, premises wiring receptacles and the utilization equipmentattachment plugs shall be of the type providing for connection to the equipment grounding conductor of the flexible cordand shall be identified for Class II locations.

In Class II, Division 2 locations, premises wiring receptacles and the utilization equipmentattachment plugs shall be of the type that provides for connection to the equipment grounding conductor of the flexiblecord and shall be designed so that connection to the supply circuit cannot be made or broken while live parts areexposed.

Revise to make clear that the receptacle is part of the premises wiring and that the attachment plug ispart of the utilization equipment. There have been several instances of confusion regarding these Code requirementswith respect to cord being supplied with a plug for connection to receptacle on the utilization equipment. Such aconstruction present and arcing hazard and the potential for exposed live parts within the classified location.

Revise text to read as follows:Receptacles and attachment plugs shall be identified for the location.

(1) Receptacles. In Class II, Division 1 locations, receptacles shall be part of the premises wiring.(2) Attachment Plugs. and aAttachment plugs shall be of the type providing for connection to the equipment grounding

conductor of the flexible cord and shall be identified for Class II locations.

(1) Receptacles. In Class II, Division 2 locations, receptacles shall be part of the premises wiring.(2) Attachment Plugs. and aAttachment plugs shall be of the type that provides for connection to the equipment

grounding conductor of the flexible cord. and shall be designed so that connection to the supply circuit cannot be madeor broken while live parts are exposed.

The revised wording meets the intent of the submitter and provides more clarity.




Revise text to read as follows:Equipment installed in Class III locations shall be able to function at full rating without developing

surface temperatures high enough to cause excessive dehydration or gradual carbonization of accumulatedfibers/flyings. Organic material that is carbonized or excessively dry is highly susceptible to spontaneous ignition. Themaximum surface temperatures under operating conditions shall not exceed 165°C (329°F) for equipment that is notsubject to overloading, and 120°C (248°F) for equipment (such as motors or power transformers) that may beoverloaded. In a Class III, Division 1 location, the operating temperature shall be the temperature of the equipment whenblanketed with fibers/flyings.Informational Note: For electric trucks, see NFPA 505-2011,

The current text is not clear as to if this temperature is based on operation of the equipment in free airor when the equipment is blanketed with fibers/flyings. In a Class III, Division 1 location, it would be expected that ablanket of fibers/flyings could exist under normal operating conditions. Equipment temperatures under a blanket offibers/flyings will be considerably higher than in free air due to the insulating effect of the blanket and may very wellexceed the maximum required temperatures when in free air they would not.

Revise text to read as follows:Equipment installed in Class III locations shall be able to function at full rating without developing

surface temperatures high enough to cause excessive dehydration or gradual carbonization of accumulatedfibers/flyings. Organic material that is carbonized or excessively dry is highly susceptible to spontaneous ignition. Themaximum surface temperatures under operating conditions shall not exceed 165°C (329°F) for equipment that is notsubject to overloading, and 120°C (248°F) for equipment (such as motors or power transformers) that may beoverloaded. In a Class III, Division 1 location, the operating temperature shall be the temperature of the equipment whenblanketed with the maximum amount of dust (simulating fibers/flyings) that can accumulate on the equipment.Informational Note: For electric trucks, see NFPA 505-2011,

The proposed text has been amended to provide a quantifiable measure of a blanket offibers/flyings.




Revise text to read as follows:Wiring methods shall comply with 503.10(A) or (B).

In Class III, Division 1 locations, the wiring method shall be in accordance with (1) through (4):(1) Rigid metal conduit, Type PVC conduit, Type RTRC conduit, intermediate metal conduit, electrical metallic tubing,

dusttight wireways, or Type MC or MI cable with listed termination fittings.(2) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725 including installation in cable

tray systems. The cable shall be terminated with listed fittings.(3) Type ITC and Type ITC-ER cable as permitted in 727.4 and terminated with listed fittings.(4) Type MC, MI, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single layer,

with a space not less than the larger cable diameter between the two adjacent cables, shall be the wiring methodemployed.

Informational Note: For further information on construction, testing andmarking of cables, cable fittings, and cord connectors,see UL 2225, .


The scope of UL 2225 does not cover fittings for Class III locations.

_______________________________________________________________________________________________14-100 Log #2796 NEC-P14



Informational Note: See 503.30(B) for grounding requirements where flexible conduit (FMC) is used."Flexible Metal Conduit" is also referred to as “FMC”






Revise text to read as follows:(1) Rigid metal conduit, Type PVC conduit, Type RTRC conduit, intermediate metal conduit, electrical

metallic tubing (EMT), dusttight wireways, or Type MC or MI cable with listed termination fittings."electrical metallic tubing" is also referred to as “EMT”

Suggest that "EMT" be added to all references. This will make finding all references to "electrical metallic tubing" easierand more reliable.[The following files are related: 100_EMT, 225_EMT, 230_EMT, 250_EMT, 300_EMT, 334_EMT, 374_EMT, 392_EMT,



_______________________________________________________________________________________________14-102 Log #2372 NEC-P14



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

Pendant luminaires shall be suspended by stems of threaded rigid metal conduit (RMC),threaded intermediate metal conduit, threaded metal tubing of equivalent thickness, or by chains with approved fittings.For stems longer than 300 mm (12 in.), permanent and effective bracing against lateral displacement shall be providedat a level not more than 300 mm (12 in.) above the lower end of the stem, or flexibility in the form of an identified fittingor a flexible connector shall be provided not more than 300 mm (12 in.) from the point of attachment to the supportingbox or fitting.


and more reliable.






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

Pendant luminaires shall be suspended by stems of threaded rigid metal conduit, threadedintermediate metal (IMC) conduit, threaded metal tubing of equivalent thickness, or by chains with approved fittings. Forstems longer than 300 mm (12 in.), permanent and effective bracing against lateral displacement shall be provided at alevel not more than 300 mm (12 in.) above the lower end of the stem, or flexibility in the form of an identified fitting or aflexible connector shall be provided not more than 300 mm (12 in.) from the point of attachment to the supporting box orfitting..




_______________________________________________________________________________________________14-104 Log #2829 NEC-P14



(2) Liquidtight flexible metal conduit (LFMC) with listed fittings,

Informational Note: See 503.30(B) for grounding requirements where flexible conduit (LFMC) is used.

Liquidtight flexible metal conduit (LFMC) shall include an equipmentbonding jumper of the wire type in compliance with 250.102.












_______________________________________________________________________________________________14-105a Log #CP1407 NEC-P14


Add a new 503.10(A)(3)(6) to read:(6) For elevator use, an identified elevator cable, type EO, ETP, or ETT, and as shown under the “use” column in Table

400.4 for “Hazardous (classified) locations” and terminated with listed dusttight fittings.Proposal 6-88 correctly identifies a situation where elevator cables are shown in Table 400.4 for

“hazardous (classified) locations”, but the wiring method is not currently permitted in Chapter 5. The Panel agrees withthe submitter's substantiation in Proposal 6-88, however the Panel disagrees that it justifies removal of their use inhazardous (classified) locations. This proposal addresses the submitter’s substantiation and corrects this correlationproblem in Chapter 5.

_______________________________________________________________________________________________14-106 Log #2478 NEC-P14


Revise text to read as follows:(4) Type MC, MI, TC or TC-ER cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single

layer, with a space not less than the larger cablediameter between the two adjacent cables, shall be the wiring method employed. The cable shall be terminated withlisted fittings.

Add Type TC-ER cable terminated with listed fittings. Other Extended Run cable constructions arecurrently permitted. Type PLTC-ER, Type ITC-ER and Type TC-ER are all built to the same requirements. Add therequirement for termination with listed fittings as is required for these types of cables in 501.10(B), 50210(B), 505.15(C)and 506.15(C).




Revise text to read as follows:Grounding and Bonding — Class III, Divisions 1 and 2. Wiring and equipment in Class III, Division 1 and 2

locations shall be grounded as specified in Article 250 andwith the following additional requirements in 503.30(A) and (B).(A) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding

purposes, but bonding jumpers with proper fittings or otherapproved means of bonding shall be used. Such means of bonding shall apply to all intervening raceways, fittings,boxes, enclosures, and so forth, between Class III locations and the point of grounding for service equipment or point ofgrounding of a separately derived system.Exception: The specific bonding means shall only be required to the nearest point where the grounded circuit

conductor and the grounding electrode conductor are connected together on the line side of the building or structuredisconnecting means as specified in 250.32(B) if the branch-circuit overcurrent protection is located on the load side ofthe disconnecting means.


jumper of the wire type in compliance with 250.102.Exception: In Class III, Division 1 and 2 locations, the bonding jumper shall be permitted to be deleted where all of the

following conditions are met:(1) Listed liquidtight flexible metal 1.8 m (6 ft) or less in length, with fittings listed for grounding, is used.(2) Overcurrent protection in the circuit is limited to 10 amperes or less.(3) The load is not a power utilization load.Grounding and Bonding. Grounding and bonding shall comply with Article 250.Informational Note: See 250.100 for additional bonding requirements in hazardous (classified) locations.




_______________________________________________________________________________________________14-108 Log #1965 NEC-P14


In the title of this subsection add the words “and Bonding” after the word grounding to read asfollows:

The section is about bonding around sections of liquidtight flexible metal conduit, however, bonding isnot mentioned in the title.

In the title of this subsection add the words “and Bonding” after the word grounding to read as follows:

Section 503.30(B) deals only with bonding conductors.







_______________________________________________________________________________________________14-110 Log #2761 NEC-P14



Typo missing word “conduit”.

_______________________________________________________________________________________________14-111 Log #1754 NEC-P14

_______________________________________________________________________________________________David Wechsler, Lake Jackson, TX

***Insert Include Rec Here***

***Insert Include Sub Here***

The proposed language belongs in a product standard, not in an installation Code. This proposalbased on NFPA 493-1978 would be in direct conflict with at least two U. S. documents on intrinsic safety.




Revise text to read as follows:This article covers the installation of intrinsically safe (I.S.) apparatus, wiring, and systems for Class I, II,

and III locations.Informational Note: For further information, see ANSI/ISA-RP12.06.01-2003,

Apparatus in which the circuits are not necessarily intrinsically safe themselves but that affectthe energy in the intrinsically safe circuits and are relied on to maintain intrinsic safety. Associated apparatus may beeither of the following:electrical apparatus which contains both intrinsically safe circuits and non-intrinsically safe circuits and is constructed sothat the non-intrinsically safe circuits cannot adversely affect the intrinsically safe circuitsAssociated apparatus may be either:a) electrical equipment which has another type of protection for use in the appropriate hazardous (classified) locationb) electrical equipment not so protected and which, therefore, is not normally used within an appropriate hazardous

(classified) location, for example a recorder which is not itself in an explosive atmosphere, but is connected to athermocouple situated within an explosive atmosphere where only the recorder input circuit is intrinsically safe.(1) Electrical apparatus that has an alternative-type protection for use in the appropriate hazardous (classified) location(2) Electrical apparatus not so protected that shall not be used within a hazardous (classified) locationInformational Note No. 1: Associated apparatus has identified intrinsically safe connections for intrinsically 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 is a network

designed to limit the energy (voltage and current) available to the protected circuit in the hazardous (classified) location,under specified fault conditions.

See the definition in 500.2.Intrinsically safe circuits in which the possible interconnections have not been

evaluated and identified as intrinsically safe.Apparatus in which all the circuits are intrinsically safe.

A circuit in which 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: Test conditions are described in ANSI/UL 913-20111997,

.An assembly of interconnected intrinsically safe apparatus, associated apparatus, and

interconnecting cables, 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.

An electrical component or combination of components of simple construction with well definedelectrical parameters that does not generate more than 1.5 volts, 100 milliamps, and 25 milliwatts, or a passivecomponent that does not dissipate more than 1.3 watts and is compatible with the intrinsic safety of the circuit in which itis used.Informational Note: The following apparatus are examples of simple apparatus:(a) Passive components, for example, switches, junction boxes, resistance temperature devices, and simple

semiconductor devices such as LEDs(b) Sources of stored energy consisting of single components in simple circuits with well-defined parameters, for

example, capacitors or inductors, whose values are considered when determining the overall safety of the system(c) Sources of generated energy, for example, thermocouples and photocells, which do not generate more than 1.5 V,

100 mA, and 25 mWExcept as modified by this article, all applicable articles of this shall apply.

All intrinsically safe apparatus and associated apparatus shall be listed.

Intrinsically safe apparatus, associated apparatus, and other equipment shall be installed in


Report on Proposals – June 2013 NFPA 70accordance with the control drawing(s).

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 require additional

overvoltage protection at the inputs to limit any possible fault voltages to less than the Um marked on the product.Intrinsically safe apparatus shall be permitted to be installed in any hazardous (classified) location for

which it has been identified. General-purpose enclosures shall be permitted for intrinsically safe apparatus.Associated apparatus shall be permitted to be installed in any hazardous (classified) location for which it has 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 the flammablegases or vapors, flammable liquids, combustible dusts, or ignitable fibers/flyings present.

General purpose enclosures shall be permitted for Intrinsically Safe Apparatus and Associated Apparatus unlessotherwise specified in the manufacturer’s documentation.

For simple apparatus, the maximum surface temperature can be determined from the values of the output power fromthe associated apparatus or apparatus to which it is connected to obtain the temperature class. The temperature classcan be determined by:(1) Reference to Table 504.10(B)(2) Calculation using the following equation:

+where:

= surface temperature= output power marked on the associated apparatus or intrinsically safe apparatus= thermal resistance of the simple apparatus

= 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 classified as T5 if their

surface temperature does not exceed 150°C.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 generated energy, for example, thermocouples and photocells, which do not generate more than 1.5 V,

100 mA, and 25 mWAny of the wiring methods suitable for unclassified locations, including those covered by

Chapter 7 and Chapter 8, shall be permitted for installing intrinsically safe apparatus. Sealing shall be as provided in504.70, and separation shall be as provided in 504.30.

Conductors of intrinsically safe circuits shall not be placed in anyraceway, cable tray, or cable with conductors of any nonintrinsically safe circuit.

Informational Note: No. 20 gauge sheet metal partitions 0.91 mm (0.0359 in.) or thicker are generally consideredacceptable.

Informational Note: Cables meeting the requirements of Articles 330 and 332 are typical of those consideredacceptable.

Informational Note: Nonincendive field wiring circuits are described in 501.10(B)(3), 502.10(B)(3), 503.10(B)(3),505.15(C)(1)(g), and 506.15(C)(7).


Report on Proposals – June 2013 NFPA 70Conductors of intrinsically safe circuits shall be secured so that any conductor that might come

loose from a terminal is unlikely to come into contact with another terminal. The conductors shall be separated fromconductors of nonintrinsically safe circuits by one of the methods in (1) through (4).(1) Separation by at least 50 mm (2 in.) from conductors of any nonintrinsically safe circuits.(2) Separation from conductors of nonintrinsically safe circuits by use of a grounded metal partition 0.91 mm (0.0359

in.) or thicker.(3) Separation from conductors of nonintrinsically safe circuits by use of an approved insulating partition which shall

extend to within 1.5 mm of the enclosure walls.(4) Where either (1) all of the intrinsically safe circuit conductors or (2) all of the nonintrinsically safe circuit conductors

are in grounded metal-sheathed or metalclad cables where the sheathing or cladding is capable of carrying fault currentto ground.Informational Note No. 1: Cables meeting the requirements of Articles 330 and 332 are typical of those considered

acceptable.Informational Note No. 2: The use of separate wiring compartments for the intrinsically safe and nonintrinsically safe

terminals is a typical method of complying with this requirement.Informational Note No. 3: Physical barriers such as grounded metal partitions or approved insulating partitions or

approved restricted access wiring ducts separated from other such ducts by at least 19 mm (3/4 in.) can be used to helpensure the required separation of the wiring.

Conductors and cables of intrinsically safe circuits run in otherthan raceway or cable tray systems shall be separated by at least 50 mm (2 in.) and secured from conductors andcables of any nonintrinsically safe circuits.

The clearance between two terminals for connection of fieldwiring of different intrinsically safe circuits shall be at least 6 mm (0.25 in.), unless this clearance is permitted to bereduced by the control drawing. Different intrinsically safe circuits shall be separated from each other by one of thefollowing means:(1) The conductors of each circuit are within a grounded metal shield.(2) The conductors of each circuit have insulation with a minimum thickness of 0.25 mm (0.01 in.).

(C) The clearance between the uninsulated parts of field wiring conductors connected toterminals and grounded metal or other conducting parts shall be at least 3 mm (0.125 in.).

Intrinsically safe apparatus, enclosures, and raceways,if of metal, shall be connected to the equipment grounding conductor.Informational Note: In addition to an equipment grounding conductor connection, a connection to a grounding electrode

may be needed for some associated apparatus, for example, zener diode barriers, if specified in the control drawing.See ANSI/ISA-RP12.06.01-2003,

.Associated apparatus and cable shields shall be grounded in

accordance with the required control drawing. See 504.10(A).Informational Note: Supplementary connection(s) to the grounding electrode may be needed for some associated

apparatus, for example, zener diode barriers, if specified in the control drawing. See ANSI/ISA-RP12.06.01-2003,

.Where connection to a grounding electrode is required, the grounding

electrode shall be as specified in 250.52(A)(1), (A)(2), (A)(3), and (A)(4) and shall comply with 250.30(A)(4). Sections250.52(A)(5), (A)(7), and (A)(8) shall not be used if any of the electrodes specified in 250.52(A)(1), (A)(2), (A)(3), or(A)(4) are present.

In hazardous (classified) locations, intrinsically safe apparatus shall be bonded in thehazardous (classified) location in accordance with 250.100.

In unclassified locations, where metal raceways are used for intrinsically safe system wiring inhazardous (classified) locations, associated apparatus shall be bonded in accordance with 501.30(A), 502.30(A),503.30(A), 505.25, or 506.25 as applicable.

Conduits and cables that are required to be sealed by 501.15, 502.15, 505.16, and 506.16 shall be


Report on Proposals – June 2013 NFPA 70sealed to minimize the passage of gases, vapors, or dusts. Such seals shall not be required to be explosionproof orflameproof but shall be identified for the purpose of minimizing passage of gases, vapors, or dusts under normaloperating conditions and shall be accessible.

Labels required by this section shall be suitable for the environment where they are installedwith consideration given to exposure to chemicals and sunlight.

Intrinsically safe circuits shall be identified at terminal and junction locations in a manner that isintended to prevent unintentional interference with the circuits during testing and servicing.

Raceways, cable trays, and other wiring methods for intrinsically safe system wiring shall be identified withpermanently affixed labels with the wording “Intrinsic Safety Wiring” or equivalent. The labels shall be located so as tobe visible after installation and placed so that they may be readily traced through the entire length of the installation.Intrinsic safety circuit labels shall appear in every section of the wiring system that is separated by enclosures walls,partitions, or floors. Spacing between labels shall not be more than 7.5 m (25 ft).

Informational Note No. 1: Wiring methods permitted in unclassified locations may be used for intrinsically safe systemsin hazardous (classified) locations. Without labels to identify the application of the wiring, enforcement authorities cannotdetermine that an installation is in compliance with this .Informational Note No. 2: In unclassified locations, identification is necessary to ensure that nonintrinsically safe wire willnot be inadvertently added to existing raceways at a later date.

Color coding shall be permitted to identify intrinsically safe conductors where they are colored lightblue and where no other conductors colored light blue are used. Likewise, color coding shall be permitted to identifyraceways, cable trays, and junction boxes where they are colored light blue and contain only intrinsically safe wiring.

Revise 504 to align with intrinsically safe products standards such as ANSI/ISA-60079-11 andANSI/UL 913. Additionally to delete some duplication within this section of the NEC.

Accept the submitter's proposed amendments with the following additional changes:(1) Reinstate the date to the reference to ANSI/ISA-RP12.06.01 wherever cited..(2) Reinstate the Informational Note to the definition of Intrinsically Safe Circuit and amend to read: "Informational

Note: Test conditions are described in ANSI/UL 913-2011, Standard for Safety, Intrinsically Safe Apparatus andAssociated Apparatus for Use in Class I, II, and III, Division 1, Hazardous (Classified) Locations."(3) Add U.S. customary units conversion to the metric measurement in 504.30(A)(2)(3).

(1) The date has been reinstated in accordance with 3.3.7.4 of the Regulations GoverningCommittee Projects.(2) The reference to UL 913 has been reinstated, since there was no substantiation for its deletion. Also, the date has

been corrected to the current edition.(3) The measurement conversion was inadvertently omitted.




Revise as follows:Informational Note: Change ANSI/ISA-RP12.06.01-2003, Recommended Practice for Wiring Methods for Hazardous

(Classified) Locations Instrumentation – Part 1: Intrinsic Safety to ANSI/ISA-RP12.06.01, Recommended Practice forWiring Methods for Hazardous (Classified) Locations Instrumentation – Part 1: Intrinsic Safety.


Paragraph 3.3.7.4 of the Regulations Governing Committee Projects requires dated references toStandards.

_______________________________________________________________________________________________14-114 Log #1222 NEC-P14


Revise text to read as follows: Apparatus in which the circuits are not necessarily intrinsically safe themselves but that affect

the energy in the intrinsically safe circuits and are relied on to maintain intrinsic safety. Associated apparatus may beeither of the following:(1) Electrical apparatus that has an alternative-type 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

Associated apparatus has identified intrinsically safe connections for intrinsically safeapparatus and also may have connections for nonintrinsically safe apparatus.

An example of associated apparatus is an intrinsic safety barrier, which is a networkdesigned to limit the energy (voltage and current) available to the protected circuit in the hazardous (classified) location,under specified fault conditions.

: Associated apparatus may be either of the following:(1) Electrical apparatus that has an alternative-type 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.


Paragraph 2.3.2.2 of the NFPA Manual of Style does not require definitions to be in a singlesentence, Also see panel action on Proposal 14-112.



_______________________________________________________________________________________________Nicholas Ludlam, Reading

Revise text to read as follows:For simple apparatus, the maximum surface temperature can be determined from the values of the output power from

the associated apparatus or apparatus to which it is connected to obtain the temperature class. The temperature classfor Class I can be determined by:(1) Reference to Table 504.10(B)(1)(2) Calculation using the following equation:

where:= surface temperature= output power marked on the associated apparatus or intrinsically safe apparatus= thermal resistance of the simple apparatus= 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 classified as T5 if theirsurfacetemperature does not exceed 150°C.

***INSERT TABLE 504-10(B)(1) HERE***

Additionally, the maximum temperature for Class II and Class III or Zone 20, 21 and 22 can be determined byreference to Table 504.10(B)(2).

***INSERT TABLE 504-10(B)(2) HERE***

The maximum power permitted for components immersed in dust is higher than that permitted forcomponents in a gas or vapor.This additional information provided would permit the marking of T135°C for Zones 20, 21 or 22 and would not exceedthe 165°C limit for carbonaceous dusts in Class III.

The Proposal would allow exceeding the temperatures permitted for Class III.




Add text to read as follows:(B) Location. Intrinsically safe apparatus shall be permitted to be installed in any hazardous (classified) location for

which it has been identified.General-purpose enclosures shall be permitted for intrinsically safe apparatus.Associated apparatus shall be permitted to be installed in any hazardous (classified) location for which it has been

identified or, if protected by other means, permitted by Articles 501 through 503, and Article 505 and Article 506.Article 506 for Zone 20, 21 and 22 also includes intrinsically safe and associated apparatus protection

techniques and the reference to Article 506 is missing.

See the panel action on Proposal 14-117.

_______________________________________________________________________________________________14-117 Log #2479 NEC-P14


Revise text to read as follows:Intrinsically safe apparatus shall be permitted to be installed in any hazardous (classified) location for

which it has been identified. General-purpose enclosuresshall be permitted for intrinsically safe apparatus.Associated apparatus shall be permitted to be installed in any hazardous (classified) location for which it has been

identified or, if protected by other means, permitted by Articles 501 through 503, Article 505 and Article 506.Add reference to Article 506 for permitted installation of associated apparatus.

_______________________________________________________________________________________________14-118 Log #1431 NEC-P14


Add text to read as follows:Any of the wiring methods suitable for unclassified locations, including those covered by

Chapter 7 and Chapter 8, shall be permitted for installing intrinsically safe apparatus. Sealing shall be as provided in504.70, and separation shall be as provided in 504.30. The diameter of individual conductors or strands ofmulti-stranded conductors within the hazardous (classified) location shall not be less than AWG 38 (0.00797mm2).

With the advent of higher power intrinsically safe systems such as the Fieldbus Intrinsically SafeConcept (FISCO), short circuit currents of over 380 mA may occur. As an example; at an ambient of 40 °C and for acurrent of 430 mA, a copper wire with a crosssectional area of 0.00797mm2 will exhibit a temperature rise ofapproximately 45°C. AWG 38 (0.00797mm2) is chosen to prevent a possible high temperature in the wiring due toself-heating.

The language of the proposal is not enforceable in practice, as measuring the diameter of individualwire strands is exceedingly difficult in the field.





(4)

“Mineral-Insulated Metal-Sheathed Cable” is also referred to as “MI” and “Article 332”Suggest that "MI" be added to all references. This will make finding all references to " Mineral-Insulated

Metal-Sheathed Cable" easier and more reliable.Also note that 504.30(A)(1) Exception 2 text and 504.30(A)(2) text are identical. It may be appropriate that the text is

an exception to one part and an subpart of another, but restricting might be reasonable.

Not all grounded metal-sheathed cables are Type MI. In addition, the proposal does not improvethe usability of the Code.

_______________________________________________________________________________________________14-120 Log #1597 NEC-P14

_______________________________________________________________________________________________Charles E. Beck, Tetra Tech

Revise text to read as follows:Informational Note: Nonincendive field wiring...503.10(B)(3) 503.10(A)(4) ...".

Incorrect citation of the paragraph within 503.

The panel notes that the text in question is the Informational Note to Exception No. 4 to504.30(A)(1).

_______________________________________________________________________________________________14-121 Log #1746 NEC-P14



"metal clad cable" is referred to in several ways: "metal clad cable" & "type MC"Suggest that "MC" be added to all references. This will make finding all references to "metal clad cable" easier and

more reliable.[These files form a group for this purpose MC_110, MC_250, MC_250, MC_300, MC_392, MC_396, MC_424, MC_504,

MC_551, MC_552, MC_725, MC_800, MC_820, MC_830, MC_840]

The proposal does not improve the usability of the Code.




Revise text to read as follows:504.30(A)(1) Exception No. 2:Informational Note: Type MC and MI cables Cables meeting the requirements of Articles 330 and 332 are typical of

those considered acceptable.504.30(A)(2) (4)Informational Note: Type MC and MI cables Cables meeting the requirements of Articles 330 and 332

are typical of those considered acceptable."Metal-Clad Cable" is also referred to as “MC” & “Article 330”

Suggest that "MC" be added to all references. This will make finding all references to "Metal Clad Cable" easier andmore reliable.“Mineral-Insulated Metal-Sheathed Cable” is also referred to as “MI” and “Article 332”Suggest that "MI" be added to all references. This will make finding all references to " Mineral-Insulated

Metal-Sheathed Cable" easier and more reliable.

Not all grounded metal-sheathed cables are Type MI. In addition, the proposal does not improvethe usability of the Code.

_______________________________________________________________________________________________14-123 Log #1432 NEC-P14


Informational Note: Nonincendive field wiring circuits are described in 501.10(B)(3), 502.10(B)(3), and 503.10(B)(3),505.15(C)(1)(g), and 506.15(C)(7).

The reference in 505.15(C)(1)(g) was modified during the last Code cycle to replace nonincendive fieldwiring with Intrinsic safety type of protection “ic”. A companion proposal has been submitted to modify 506.15(C)(7).


Informational Note: Nonincendive field wiring circuits are described in 501.10(B)(3), 502.10(B)(3), and503.10(B)(3)(A)(4), 505.15(C)(1)(g), and 506.15(C)(7).

This action correlates with action on Proposal 14-120.




Revise text to read as follows:Informational Note: Nonincendive field wiring circuits are described in 501.10(B)(3), 502.10(B)(3),

503.10(B)(3)503.10(A)(4), 505.15(C)(1)(g) and 506.15(C)(7).The NEC 501.10(B)(3) and 505.15(C)(g) do not reference the rules for nonincendive field wiring. This

proposal corrects the problem by referencing the proper NEC sections.


_______________________________________________________________________________________________14-125 Log #2348 NEC-P14


Revise text to read as follows:Informational Note: Nonincendive field wiring circuits are described in 501.10(B)(3), 502.10(B)(3),

503.10(B)(3)503.10(A)(4), 505.15(C)(1))(g), and 506.15(C)(7).The problem here is that NEC 503.10(B)(3) is an incorrect reference. It should be NEC 503.10(A)(4).

Also, NEC 505.15(C)(1)(g) does not contain any rules for nonincendive field wiring circuits nor are there any rules forsuch wiring in the entirety of Article 505.


_______________________________________________________________________________________________14-126 Log #2009 NEC-P14


Add new text to read as follows:(A) Intrinsically Safe Apparatus, Enclosures, and Raceways Informational Note: Change ANSI/ISA-RP12.06.01-2003,

to ANSI/ISA-RP12.06.01,.

(B) Associated Apparatus and Cable Shields Informational Note: Change ANSI/ISA-RP12.06.01-2003,to

ANSI/ISA-RP12.06.01,


Paragraph 3.3.7.4 of the Regulations Governing Committee Projects requires dated references toStandards. The publication date of this referenced document is correct as stated in the 2011 edition of the NEC.



_______________________________________________________________________________________________David Wechsler, American Chemical Council / Rep. American Chemistry Council

****Include NEC_L1349_R Here*****

Zone 0, Zone 1 and Zone 2 may only be applied to flammable gases, vapors or combustible liquidswhich are addressed in Article 505. The defined term “Class I” in Article 500 does not need to be repeated. As anexample, ‘ethylene’ may be used in a location considered to be a Class I, Zone 1 , and a Zone 1 using ‘ethylene’, doesnot change the classification nor the material; the use of the term “Class I” has no real meaning in this condition.When Article 505 was first introduced, it was felt that additional clarification was needed. We have moved past this pointin time. It is understood that completely removing the term ‘Class I’ in Article 505 may be a labeling and cost issue.However the action from this proposal makes the use of the term ‘Class 1’ in Article 505 optional.This action will also reduce confusion with NFPA 30 and its use of Class I flammable liquids.

The proposed change does not improve the usability of the Code and potentially causes confusionfor the inspection and user community.

_______________________________________________________________________________________________14-128 Log #1437 NEC-P14


***INCLUDE NEC/L1437/R/A2013/ROP HERE***

Article 505 only relates to explosion hazards that may exist due to flammable gases, vapors, or liquidsand the title does not include the Class I designation. Zone 0, 1, and 2 locations are already defined those areas inwhich flammable gases or vapors are or may be present in the air in quantities sufficient to produce explosive or ignitiblemixtures, thereby making the “Class I” designation redundant. Deleting “Class I” from Article 505 would bring it intoalignment with Article 506 which is titled “Zone 20, 21, and 22Locations for Combustible Dusts, Fibers, and Flyings. This does not affect every reference to Class I as some of thosequoted in Article 505 refer to Divisions or to standard titles.

The proposed change does not improve the usability of the Code and potentially causes confusionfor the inspection and user community.




Revise text to read as follows:Flameproof “d” Informational Note: ANSI/ISA-60079-1 (12.22.01)-2008,

ANSI/ISA-60079-1 (12.22.01),

Intrinsic Safety “i” Informational Note 1: ANSI/ISA-60079-11 (12.02.01)-2009,ANSI/ISA-60079-11 (12.02.01),

Pressurization “p” Informational ANSI/ISA-60079-2 (12.04.01)-2004,ANSI/ISA-60079-2 (12.04.01),

Type of Protection “n” Informational Note: ANSI/ISA-60079-15 (12.12.02)-2008,ANSI/ISA-60079-15 (12.12.02),


Revise text to read as follows:Flameproof “d” Informational Note: ANSI/ISA-60079-1 (12.22.01)-2008,

ANSI/ISA-60079-1-2009 (12.22.01),

Intrinsic Safety “i” Informational Note 1: ANSI/ISA-60079-11 (12.02.01)-2009,ANSI/ISA-60079-11-2011 (12.02.01),

Pressurization “p” Informational ANSI/ISA-60079-2 (12.04.01)-2004,ANSI/ISA-60079-2-2010 (12.04.01),

Type of Protection “n” Informational Note: ANSI/ISA-60079-15 (12.12.02)-2008,ANSI/ISA-60079-15-2009 (12.12.02),

Paragraph 3.3.7.4 of the Regulations Governing Committee Projects requires dated references toStandards. The publication dates inserted in the Panel Action are correct for the referenced documents.




Add new text to read as follows:Electromagnetic radiation at wavelengths in vacuum between the region of transition to X-rays and

the region of transition to radio waves, that is approximately between 1 nm and 1,000 ìm. Informational Note: Foradditional information on types of protection that can be applied to minimize the risk of ignition in explosive gasatmospheres from optical radiation in the wavelength range from 380 nm to 10 ìm, see ANSI/ISA–60079-28 (12.21.02),

Type of protection to minimize the risk of ignition in explosive gas atmospheres fromoptical radiation where visible or infrared radiation is incapable of producing sufficient energy under normal or specifiedfault conditions to ignite a specific hazardous atmospheric mixture. Informational Note: See ANSI/ISA–60079-28(12.21.02),

Type of protection to minimize the risk of ignition in explosive gas atmospheresfrom optical radiation where radiation is confined inside optical fibre or other transmission medium under normalconstructions or constructions with additional mechanical protection based on the assumption that there is no escape ofradiation from the confinement. Informational Note: See ANSI/ISA–60079-28 (12.21.02),

Type of protection to minimize the risk of ignition in explosive gas atmospheres from optical radiation where radiation isconfined inside protected or unprotected optical fibre or other transmission medium with interlock cut-off provided toreliably reduce the unconfined beam strength to safe levels within a specified time. Informational Note: SeeANSI/ISA–60079-28 (12.21.02),

Optical fibre cable protected from releasing optical radiation into the atmosphereduring normal operating conditions and foreseeable malfunctions by additional armouring, conduit, cable tray orraceway. Informational Note: See ANSI/ISA–60079-28 (12.21.02),

● The 2011 edition of the NEC does not address the potential for optical radiation to cause ignition inan explosive atmosphere. It does address optical fiber cables, but not from the perspective of the potential to causeignition.● With the publication of ANSI/ISA-60079-28 (12.21.02),

, there are now published US national requirements that address thepotential risk of ignition associated with optical radiation in Zone classified areas.● This ANSI/ISA standard is harmonized with IEC 60079-28:2006,

, and aligned with ANSI/ISA-TR12.21.01,, for Division classified areas.

● ANSI/ISA-60079-28 (12.21.02) defines three types of protection that can be applied to prevent ignition by opticalradiation in potentially explosive atmospheres. These types of protection are: 1) inherently safe optical radiation, type ofprotection “op is”; 2) protected optical radiation, type of protection “op pr”; and 3) optical system with interlock, type ofprotection “op sh”.● This proposal introduces these types of protection, along with the general term ‘optical radiation’ and one of the

more common applications of optical radiation in explosive atmospheres, ‘protected optical fiber cable’.● Additional proposals are being submitted to introduce related, supporting text under 505.8 and 505.9.

It should be noted that the sources of the optical radiation are electrical equipment. Therefore this proposal isnecessary for inclusion in the NEC.

There is no need to define terms that are not used in the Code.




Revise text to read as follows:Informational Note No. 1: See ANSI/ISA-60079-18 (12.23.01)-2009,

Explosive atmospheres - Part 18: Equipmentprotection by encapsulation "m" ; IEC 60079–18-1992,

and ANSI/UL 60079-18,Explosive atmospheres - Part 18: Equipment protection by encapsulation "m".

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

New editions of ANSI/ISA-60079-18 (12.23.01) and ANSI/UL 60079-18 now include three levels ofprotection by Encapsulation, the previously available “ma” and “mb” for use in Class I, Zone 0 and Zone 1 locationsrespectively, and a new level of protection “mc” for use in Class I, Zone 2 locations.The reference to IEC 60079-18 is obsolete as there is US adoption with National differences by ISA and UL of this IEC

document.For definition purposes, all types of encapsulation can be referred as Encapsulation “m”.

Revise text to read as follows:Informational Note No. 1: See ANSI/ISA-60079-18 (12.23.01)-2009,

Explosive atmospheres - Part 18: Equipmentprotection by encapsulation "m" ; IEC 60079–18-1992,

and ANSI/UL 60079-18-2009,Explosive atmospheres - Part 18: Equipment protection by encapsulation "m".

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

Edition dates have been replaced/added in accordance with 3.3.7.4 of the Regulations GoverningCommittee Projects.




Revise text to read as follows:(A) Documentation for Industrial Occupancies Informational Note: ANSI/ISA-TR(12.24.01)-1998 (IEC 60079-10 Mod),

ISA-TR12.24.01 (IEC 60079-10 Mod),

(B) Reference Standards Informational Note 2: ANSI/ISA-TR(12.24.01)-1998 (IEC 60079-10 Mod),

ISA-TR12.24.01 (IEC 60079-10 Mod),

Informational Note 7: ANSI/ISA-60079-0 (12.00.01)-2005,ANSI/ISA-60079-0 (12.00.01),


Do not accept the changes to ISA-TR12.24.01 (IEC 60079-10 Mod).Accept the third change, but add the correct publication date of 2009.

The current date of ISA-TR12.24.01 (IEC 60079-10 Mod) is 1998, so the current text is correct.The date of publication for the third reference is added in accordance with Paragraph 3.3.7.4 of the RegulationsGoverning Committee Projects.

_______________________________________________________________________________________________14-133 Log #3201 NEC-P14


Replace "1997" date reference to ANSI/API RP505 to "2012" as indicated below.Informational Note: For examples of area classification drawings, see ANSI/API RP 505-1997 2012.

1,This and the companion proposals propose to update the date references to ANSI/API RP 505. The

latest edition of ANSI/API RP 505 is in revision mode and is anticipated to be released by API in 2012.





Replace "1997" date reference to ANSI/API RP505 to "2012" as indicated below.ANSI/API RP 505-1997 2012,

1,This and the companion proposals propose to update the date references to ANSI/API RP 505. The

latest edition of ANSI/API RP 505 is in revision mode and is anticipated to be released by API in 2012.


_______________________________________________________________________________________________14-135 Log #3203 NEC-P14


Replace"1997" date reference to ANSI/API RP505 to "2012" as indicated below.Informational Note No. 4: For further information on ventilation, see NFPA 30-2008,

and ANSI/API RP 505 1997 2012,

This and the companion proposals propose to update the date references to ANSI/API RP 505. Thelatest edition of ANSI/API RP 505 is in revision mode and is anticipated to be released by API in 2012.


_______________________________________________________________________________________________14-136 Log #2013 NEC-P14


Revise text to read as follows:(B)(1) Class I, Zone 0 (2) Informational Note 1: ANSI/ISA-TR12.24.01-1998 (IEC 60079-10 Mod),

ISA-TR12.24.01 (IEC 60079-10 Mod),


Paragraph 3.3.7.4 of the Regulations Governing Committee Projects requires dated references toStandards. The publication dates inserted in the Panel Action are correct for the referenced documents.




Revise text to read as follows:505.5 Classifications of Locations(A) Classification of Locations. 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. Where pyrophoricmaterials are the only materials used or handled, these locations shall not be classified. Each room, section, or areashall be considered individually in determining its classification. Where pyrophoric materials are the only materials usedor handled, these locations are outside the scope of this article.

The language is being updated to be consistent with current language found in Section 506.5(A) andconsistent with the fact that neither NFPA 497 or NFPA 499 currently address the use of pyrophoric materials.

_______________________________________________________________________________________________14-137 Log #3204 NEC-P14


Replace "1997" date reference to ANSI/API RP505 to "2012" as indicated below.Informational Note No. 1: As a guide in determining when flammable gases or vapors are present continuously or for

long periods of time, refer to ANSI/API RP 505 -1997 2012,






Revise text to read as follows:Class I, Zone 0, 1, and 2 locations are those in which flammable gases or

vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I, Zone 0,1, and 2 locations shall include those specified in 505(B)(1), (B)(2), and (B)(3).

A Class I, Zone 0 location is a location in which(1) Ignitible concentrations of flammable gases or vapors are present continuously, or(2) Ignitible concentrations of flammable gases or vapors are present for long periods of time.Informational Note No. 3: It is not good practice to install electrical equipment in Zone 0 locations except when the

equipment is essential to the process or when other locations are not feasible. [See 505.5(A) Informational Note No. 2.]If it is necessary to install electrical systems in a Zone 0 location, it is good practice to install intrinsically safe systems asdescribed by Article 504.Installations in Zone 0 should be avoided where ever possible [See 505.5(A) Informational Note No. 2.]. Where this is

not feasible intrinsically safe apparatus “ia” and encapsulated apparatus “ma” or a combination of intrinsically safe “ia”and encapsulation “ma” can be used [see 505.8]. Wiring methods should be suitable for the intended application.

Informational notes should contain explanatory information only. Informational Note 3 makes arecommendation in that it is ‘good practice’ to install intrinsically safe systems as described by Article 504. Apparatuslisted as Encapsulation “m” and identified for use in Zone 0 is also permitted as permitted by 505.8.505.15(A) specifies that only the wiring methods permitted by Article 504 can be used for Zone 0 applications. The

informational note should be modified and then expanded to include encapsulation.

Revise text to read as follows:Class I, Zone 0, 1, and 2 locations are those in which flammable gases or

vapors are or may be present in the air in quantities sufficient to produce explosive or ignitible mixtures. Class I, Zone 0,1, and 2 locations shall include those specified in 505(B)(1), (B)(2), and (B)(3).

A Class I, Zone 0 location is a location in which(1) Ignitible concentrations of flammable gases or vapors are present continuously, or(2) Ignitible concentrations of flammable gases or vapors are present for long periods of time.Informational Note No. 3: It is not good practice to install electrical equipment in Zone 0 locations except when the

equipment is essential to the process or when other locations are not feasible. [See 505.5(A) Informational Note No. 2.]If it is necessary to install electrical systems in a Zone 0 location, it is good practice to install intrinsically safe systems asdescribed by Article 504.

Informational Note 3 is a restatement of the existing requirements. The submitter's proposed text isnot necessary and is the part that the panel does not accept.



_______________________________________________________________________________________________William G. Lawrence, Jr., S. Yarmouth, MA

Revise text to read as follows:Group II shall be subdivided into IIC, IIB, and IIA, as noted in 505.6(A), (B), and (C), according to the nature of the gas

or vapor, for protection techniques “d,” “ia,” “ib,” “[ia],” and “[ib],” and, where applicable, “n” and “o.”.Informational Note No. 2: Verification of electrical equipment utilizing protection techniques “e,” “m,” “p,” and “q,” due to

design technique, does not require tests involving MESG or MIC. Therefore, Group II is not required to be subdivided forthese protection techniques. Group II is currently subdivided into Groups “IIA”, “IIB”, and “IIC”. Prior markingrequirements allowed some types of protection to be marked without a subdivision, showing only Group “II”. Equipmentso marked should be considered to be suitable for Group IIC applications.

The product standards have been revised such that the marking of a Group subdivision is alwaysrequired. Therefore, Group “II” is no longer a marking permitted by the product standards. The second paragraph is nolonger necessary as the first paragraph correctly states the requirement. The Informational Note needs revisions toaddress equipment markings for equipment produced prior to the changes in the product standards.

_______________________________________________________________________________________________14-140 Log #1310 NEC-P14

_______________________________________________________________________________________________Paul E. Guidry, Fluor Enterprises, Inc.

In addition to the Group IIB designation, it shall be acceptable to allow the designation of IIB+H2 on equipment toindicate that the atmosphere may contain hydrogen in addition to the normally specified Group IIB gases.

Group IIB+ H2 is equivalent to Class I, Group B as described in 500.6(A)(2).It is becoming more and more common to see equipment rated IIB+H2 since a IIC designation includes

acetylene, which isn’t encountered that often. I have provided with this proposal an excerpt from API RP 505, Section5.5.6, Table 1 which explains the situation.Note: Supporting Material is available for review at NFPA heaquarters.

"IIB+H2" is not a gas group. The current text permits this listing and application, and has beenfurther clarified by the actions on proposals 14-183 and 14-152a.




Add new text to read as follows:Informational Note No. 3– For Zone 1 locations, the available short circuit current for electrical equipment using type of

protection “e” for the field wiring connections should 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. This may require the applicationof current-limiting fuses or current-limiting circuit breakers.

The short circuit current rating of terminals and terminal blocks, according to ANSI/UL 508A, is 10,000rms symmetrical amperes unless otherwise evaluated. To align with the ratings of these components, the available shortcircuit current should be limited to corresponding values. This is consistent with the approach in Article 409 for industrialcontrol panels. This note is necessary as these terminals are used in many applications other than industrial controlpanels.

The proposed text does not meet 3.1.3 of the NEC Style Manual, as it includes potentiallynormative text.




Add new text to read as follows:This protection technique shall be permitted for equipment in Class I,

Zone 0, Zone 1 or Zone 2 locations, for which it is identified.The identified Zone depends upon the number of faults applied as part of the protection technique

evaluation.This protection technique shall be permitted for equipment in Class I, Zone 1

or Zone 2 locations for which it is identified.. The identified Zone depends upon whether or not additional mechanical protection is provided as

part of the protection technique evaluation.This protection technique shall be permitted for equipment in Class I, Zone

0, Zone 1 or Zone 2 locations, for which it is identified.The identified Zone depends upon the confinement construction and upon the shut-down time in

which the unconfined beam strength is reliably reduced to safe levels.● The 2011 edition of the NEC does not address the potential for optical radiation to cause ignition in

an explosive atmosphere. It does address optical fiber cables, but not from the perspective of the potential to causeignition.● With the publication of ANSI/ISA-60079-28 (12.21.02),

, there are now published US national requirements that address thepotential risk of ignition associated with optical radiation in Zone classified areas.● This ANSI/ISA standard is harmonized with IEC/EN 60079-28:2006,



more common applications of optical radiation in explosive atmospheres, ‘protected optical fiber cable’.● Additional proposals are being submitted to introduce related, supporting text under 505.2 and 505. 9● It should be noted that the sources of the optical radiation are electrical equipment. Therefore this proposal is


See panel action and panel statement on Proposal 14-20. Also, the standard containing theprotection techniques described in the substantiation has not been published yet.




Revise text to read as follows:Informational Note: ANSI/ISA-60079-0 (12.00.01)-2009,

ANSI/ISA-60079-0 (12.00.01),

Informational Note 3: ISA-TR12.13.03,ANSI/ISA-TR12.13.03,


Revise text to read as follows:Informational Note: ANSI/ISA-60079-0 (12.00.01)-2009,

ANSI/ISA-60079-0 (12.00.01)-2009,

Informational Note 3: ISA-TR12.13.03,ANSI/ISA-TR12.13.03-2009,

The edition dates have been added in accordance with 3.3.7.4 of the Regulations GoverningCommittee Projects.

_______________________________________________________________________________________________14-144 Log #1172 NEC-P14

_______________________________________________________________________________________________Jon D. Miller, Detector Electronics Corp.

Change the text to the following :( 1) Inadequate Ventilation. In a Class I, Zone 1 location that is so classified due to inadequate ventilation, electrical

equipment suitable for Class I, Zone 2 locations shall be permitted. Combustible gas detection equipment shall be listedfor Class I, Zone 1, for the appropriate material group, and for the detection of the specific gas or vapor to beencountered for which it is intended.( 2) Interior of a Building. In a building located in, or with an opening into, a Class I, Zone 2 location where the interior

does not contain a source of flammable gas or vapor, electrical equipment for unclassified locations shall be permitted.Combustible gas detection equipment shall be listed for Class I, Zone 1 or Class I, Zone 2, for the appropriate materialgroup, and for the detection of the specific gas or vapor to be encountered for which it is intended.( 3) Interior of a Control Panel. In the interior of a control panel contain ing instrumentation utilizing or measuring

flammable liquids, gases, or vapors, electrical equipment suitable for Class I, Zone 2 locations shall be permitted.Combustible gas detection equipment shall be listed for Class I, Zone 1, for the appropriate material group, and for thedetection of the specific gas or vapor to-be encountered for which it is intended.

The listing of the gas detector would include the gasses or vapors for which the detector is intended(not "encountered").A Methane gas detector encounters Nitrogen (within air), but the Methane gas detector is not listedfor Nitrogen.

Gas detection equipment can be intended to detect, for example, a noncombustible gas or acombustible gas other than the one to be encountered, and that would not fulfill the requirements of using gas detectionas a method of protection.




Replace "1997" date reference to ANSI/API RP505 to "2012" as indicated below.Informational Note No. 1: For further information, see to ANSI/API RP 505 -1997 2012,



_______________________________________________________________________________________________14-146 Log #3207 NEC-P14


Change "ignition temperature" to "autoignition temperature".

API RP 500, API RP 505, NFPA 497 and NFPA 499 define the term "Autoignition Temperature" or(AlT). The term "ignition temperature" is often used synonymously with autoignition temperature, but sometimesincorrectly. This proposal, along with its companion proposals, attempt to promote consistency of the terms between thestandards. The term "autoignition temperature" is used when referring to the material property of flammable liquids andvapors, which is consistent with how the term is used in NFPA497. The term "ignition temperature" is used when referring to the material property of combustible dusts, which isconsistent with how the term is used in NFPA 499.

_______________________________________________________________________________________________14-147 Log #570 NEC-P14


Change the title of Table 505.9(C)(1)(2) as follows:Gas Classification Material GroupsChange the column heading of Table 505.9(C)(1)(2) as follows:Gas Material GroupChange item (5) of 505.9(C)(2)Applicable gas classification material group(s) in accordance with Table 505.9(C)(1)(2)

This section is inconsistent as it uses the terms “gas group” and “gas classification group” whereas505.6 uses the term “material group”.




Revise as follows:The paragraph beginning "Electrical equipment of types..." can be deleted as the product standards have been revised

such that the marking of the Group subdivision is always required.The product standards have been revised such that the marking of the Group subdivision is always

required.

_______________________________________________________________________________________________14-149 Log #1435 NEC-P14


Revise artwork for Informational Note Figure 505.9(C) Zone Equipment Marking as follows:

***INSERT ART NEC_L1435_R***

The text "(not required for protection techniques indicated in 506.6 FPN No. 2)" should be deleted.As written, this Figure implies that the Group Classification “II” is not permitted for some protection

techniques which conflicts with the requirement in 505.9(B)(2). The “not required for protection techniques indicated in506.6 FPN No. 2” refers to the subdivision of the Group A, B or C. Additionally the standards referenced in theinformational notes in 505.6 no longer permit the marking of “Group II” without the sub-division C, B or A.

In addition to the submitter's proposal, in Figure 505.9(C)(2), replace "gas classification group" with "material group".The additional change correlates with the action on proposal 14-147.

_______________________________________________________________________________________________14-150 Log #1993 NEC-P14



******Insert Table 505.9(C)(2)(4) Here******

New editions of ANSI/ISA-60079-18 (12.23.01) and ANSI/UL 60079-18 now include three levels ofprotection by Encapsulation, the previously available “ma” and “mb” for use in Class I, Zone 0 and Zone 1 areasrespectively, and a new level of protection “mc” for use in Class I, Zone 2 areas.

The Panel accepts the addition of the new table entry for Type mc and the relocation of the table entry for Type m.The rest of the table remains unchanged.

The Panel notes that the revised table, as submitted is incomplete. Other methods of protectionare retained.




Revise Table 505.9(C)(2)(4) to include the following additional rows regarding ‘op’ types ofprotection after the existing row for ‘Oil immersion (ob)’ and before the existing row for ‘Pressurization (px)’, along withincluding additional associated footnotes after the existing footnotes at the bottom of the table:






more common applications of optical radiation in explosive atmospheres, ‘protected optical fiber cable’.● Additional proposals are being submitted to introduce related, supporting text under 505.2, 505.8 and elsewhere in

505.9.● It should be noted that the sources of the optical radiation are electrical equipment. Therefore this proposal is



_______________________________________________________________________________________________14-152 Log #572 NEC-P14


Add a new Exception No. 3 as follows:Cable fittings are not required by ANSI/UL 2225 to be marked with a temperature class. Add a new Exception No. 3 to

acknowledge this.Exception No. 3: Fittings for the termination of cables shall not be required to have a marked operating temperature or

temperature class.Cable fittings are not required by ANSI/UL 2225 to be marked with a temperature class.




Add to the end of the existing text:"...or a specific gas or vapor"

The current text permits this listing and application, but not the marking.

_______________________________________________________________________________________________14-153 Log #3206 NEC-P14


Change "ignition temperature" to "autoignition temperature".

API RP 500, API RP 505, NFPA 497 and NFPA 499 define the term "Autoignition Temperature" or(AlT). The term "ignition temperature" is often used synonymously with autoignition temperature, but sometimesincorrectly. This proposal, along with its companion proposals, attempt to promote consistency of the terms between thestandards. The term "autoignition temperature" is used when referring to the material property of flammable liquids andvapors, which is consistent with how the term is used in NFPA497. The term "ignition temperature" is used when referring to the material property of combustible dusts, which isconsistent with how the term is used in NFPA 499.

_______________________________________________________________________________________________14-154 Log #2346 NEC-P14



The above NEC section contains an incorrect reference. NEC 505.20(D) does not contain any rules forClass 1, Division 2 locations. This proposal revises the text for correct referencing and makes NEC 505.9(D)(1)Exception No. 2 more consistent and less confusing. NEC 505.20(B) and (C) contain rules for Class 1, Division 1 and 2locations respectively.


The reference to 505.20(A) was missing from the original text.




Revise text to read as follows:505.9(E)(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, listed conduit fittings, or listed cable fittingsshall be used.All remaining text stays the same.

This is a companion proposal to Section 500.8(E)(1) that was submitted for the 2011 Comment phase.The Comment action was to "Hold" till the 2014 Proposal phase. I had neglected to submit the same proposals toSection 505.9(E)(1) and 506.9(E)(1). The substantiation is similar.As 505.9(E)(1) is presented in the 2011 NEC, a grammatical error leaves the conduit and the cable fitting without a rule

that requires them to be listed. Because of the comma, the word "listed" ahead of "listed conduit" only applies to theconduit. The addition of the word "listed" in front of conduit fittings and cable fittings will add the listings requirements tothe conduit fittings and the cable fittings.

The Panel accepts this proposal, with the understanding that the submitter meant to underline thesecond instance of the word "listed" and not the first.

_______________________________________________________________________________________________14-156 Log #2480 NEC-P14


Revise text to read as follows:Metric threaded entries into explosionproof or flameproof equipment shall have a class of fit of at least 6g/6H and be

made up with at least five threads fully engaged forGroups C, D, IIB, or IIA and not less than eight threads fully engaged for Groups A, B, IIC, or IIB + H2. and threadengagement as shown in Table 505.9(E)(2).

***INSERT TABLE NEC_L2480_Tb505.9(E)(2) HERE ***

Revise the class of fit to align with the requirements in ANSI/UL standard covering explosionproof andflameproof equipment.

The panel has determined that it would be best to address this issue in the individual productstandards.




Add a new 505.9G to address the issue of equipment involving optical radiation in explosive gasatmospheres. This item is separate from the existing 505.9(F) regarding Optical fiber cables because, while Opticalfiber cables are equipment using optical radiation, the intent of 505.9(F) is to address the issue of cables containingconductors that are capable of carrying current, not optical radiation.

The risk of ignition from optical radiation, both inside and outsideoptical equipment, shall be considered for all electrical parts and circuits except for non-array indicator LEDs used toshow equipment status, for luminaires with divergent light sources and for optical radiation sources for Zone 2applications which comply with Class I limits for light emitting (e.g. laser) products. This includes equipment, which itselfis located outside the explosive atmosphere, but its emitted optical radiation enters such atmospheres.Informational Note: For additional information on types of protection that can be applied to minimize the risk of ignition

in explosive gas atmospheres from optical radiation in the wavelength range from 380 nm to 10 ìm, seeANSI/ISA–60079-28 (12.21.02),





more common applications of optical radiation in explosive atmospheres, ‘protected optical fiber cable’.Additional proposals are being submitted to introduce related, supporting text under 505.2, 505.8 and elsewhere in

505.9.






(e) Threaded rigid metal conduit (RMC), or threaded steel intermediate metal conduit.(f) Type PVC conduit and Type RTRC conduit shall be permitted where encased in a concrete envelope a minimum of50 mm (2 in.) thick and provided with not less than 600 mm (24 in.) of cover measured from the top of the conduit tograde. Threaded rigid metal conduit (RMC) 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 aboveground raceway. Anequipment grounding conductor shall be included to provide for electrical continuity of the raceway system and forgrounding of non–current-carrying metal parts.

(f) In industrial establishments with restricted public access, where the conditions of maintenance and supervisionensure that only qualified persons service the installation, and where metallic conduit (RMC) does not provide sufficientcorrosion resistance, listed reinforced thermosetting resin conduit (RTRC), factory elbows, and associated fittings, allmarked with the suffix -XW, and Schedule 80 PVC conduit, factory elbows, and associated fittings shall be permitted.Where seals are required for boundary conditions as defined in 505.16(C)(1)(b), the Zone 1 wiring method shall extendinto the Zone 2 area to the seal, which shall belocated on the Zone 2 side of the Zone 1–Zone 2 boundary.

(b) In each conduit run passing from a Class I, Zone 2 location into an unclassified location. The sealing fitting shall bepermitted on either side of the boundary of such location within 3.05 m (10 ft) of the boundary and shall be designed andinstalled so as to minimize the amount of gas or vapor within the Zone 2 portion of the conduit from being communicatedto the conduit beyond the seal. Rigid metal conduit (RMC) or threaded steel intermediate metal conduit shall be usedbetween the sealing fitting and the point at which the conduit leaves the Zone 2 location, and a threaded connectionshall be used at the sealing fitting. Except for listed explosion-proof reducers at the conduit seal, there shall be no union,coupling, box, or fitting between the conduit seal and the point at which the conduit leaves the Zone 2 location. Conduitsshall be sealed to minimize the amount of gas or vapor within the Class I,Zone 2 portion of the conduit from being communicated to the conduit beyond the seal. Such seals shall not be requiredto be flameproof or explosionproof but shall be identified for the purpose of minimizing passage of gases under normaloperating conditions and shall be accessible.

The cross-sectional area of the conductors permitted in a seal shall not exceed 25 percent of thecross-sectional area of a rigid metal conduit (RMC) of the same trade size unless it is specifically listed for a higherpercentage of fill.

"Rigid Metal Conduit" is also referred to as “RMC” “Metallic Conduit”Suggest that "RMC" be added to all references. This will make finding all references to "Rigid Metal Conduit" easier andmore reliable.






(e) Threaded rigid metal conduit, or threaded steel intermediate metal conduit (IMC).(f) Type PVC conduit and Type RTRC conduit shall be permitted where encased in a concrete envelope a minimum of

50 mm (2 in.) thick and provided with not less than 600 mm (24 in.) of cover measured from the top of the conduit tograde. Threaded rigid metal conduit or threaded steel intermediate metal conduit (IMC) shall be used for the last 600mm (24 in.) of the underground run to emergence or to the point of connection to the aboveground raceway. Anequipment grounding conductor shall be included to provide for electrical continuity of the raceway system and forgrounding of non–current-carrying metal parts.

(f) In industrial establishments with restricted public access, where the conditions of maintenance and supervisionensure that only qualified persons service the installation, and where metallic conduit (IMC) does not provide sufficientcorrosion resistance, listed reinforced thermosetting resin conduit (RTRC), factory elbows, and associated fittings, allmarked with the suffix -XW, and Schedule 80 PVC conduit, factory elbows, and associated fittings shall be permitted.Where seals are required for boundary conditions as defined in 505.16(C)(1)(b), the Zone 1 wiring method shall extendinto the Zone 2 area to the seal, which shall belocated on the Zone 2 side of the Zone 1–Zone 2 boundary

(b) In each conduit run passing from a Class I, Zone 2 location into an unclassified location. The sealing fitting shall bepermitted on either side of the boundary of such location within 3.05 m (10 ft) of the boundary and shall be designed andinstalled so as to minimize the amount of gas or vapor within the Zone 2 portion of the conduit from being communicatedto the conduit beyond the seal. Rigid metal conduit or threaded steel intermediate metal conduit (IMC) shall be usedbetween the sealing fitting and the point atwhich the conduit leaves the Zone 2 location, and a threaded connection shall be used at the sealing fitting. Except forlisted explosion-proof reducers at the conduit seal, there shall be no union, coupling, box, or fitting between the conduitseal and the point at which the conduit leaves the Zone 2 location. Conduits shall be sealed to minimize the amount ofgas or vapor within the Class I,Zone 2 portion of the conduit from being communicated to the conduit beyond the seal. Such seals shall not be requiredto be flameproof or explosionproof but shall be identified for the purpose of minimizing passage of gases under normaloperating conditions and shall be accessible.

.




Report on Proposals – June 2013 NFPA 70See the panel action and statement on Proposal 14-29.




Revise text to read as follows:Wiring methods shall maintain the integrity of protection techniques and shall comply with

505.15(A) through (C).In Class I, Zone 0 locations, only intrinsically safe wiring methods in accordance with Article 504

shall be permitted.Informational Note: Article 504 only includes protection technique “ia.”

In Class I, Zone 1 locations, the wiring methods in (B)(1)(a) through (B)(1)(f) 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 and supervision

ensure that only qualified persons service the installation, and where the cable is not subject to physical damage, TypeMC-HL cable listed for use in Class I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugatedmetallic sheath, an overall 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 inaccordancewith the provisions of Article 330, Part II.(c) In industrial establishments with restricted public access, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation, and where the cable is not subject to physical damage, TypeITC-HL cable listed for use in Class I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugatedmetallic sheath and an overall jacket of suitablepolymeric material, and terminated with fittings listed for the application. Type ITC-HL cable shall be installed inaccordance 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 cable shall 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 envelope a minimum of

50 mm (2 in.) thick and provided with not less than 600 mm (24 in.) of cover measured from the top of the conduit tograde. Threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for the last 600 mm (24in.) of the underground run to emergence or to the point of connection to the aboveground raceway. An equipmentgrounding conductor shall be included to provide for electrical continuity of the raceway system and for grounding ofnon–current-carrying metal parts.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .Where necessary to employ flexible connections, flexible fittings listed for Class I, Zone 1 or

Division 1 locations, or flexible cord in accordance with the provisions of 505.17 terminated with a listed cord connectorthat maintains the type of protection of the terminal compartment, shall be permitted.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .

In Class I, Zone 2 locations, the following wiring methods shall be permitted.(a) All wiring methods permitted by 505.15(B).(b) Types MC, MV, or TC cable, including installation in cable tray systems. The cable shall be terminated with listed

fittings. Single conductor Type MV cables shall beshielded or metallic-armored.(c) Type ITC and Type ITC-ER cable as permitted in 727.4 and terminated with listed fittings.(d) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, including installation in cable

tray systems. The cable shall be terminated with listed fittings.Key Informational Note: See attached.

Revise to add an Informational Note regarding the requirements for cables, cable fittings and cord


Report on Proposals – June 2013 NFPA 70connectors. There have been several instances of confusion regarding these Code requirements with respect totermination of cables with cable fittings.

Revise 505.15 to read:505.15 Wiring Methods. Wiring methods shall maintain the integrity of protection techniques and shall comply with

505.15(A) through (C).(A) Class I, Zone 0. In Class I, Zone 0 locations, only intrinsically safe wiring methods in accordance with Article 504

shall be permitted.Informational Note: Article 504 only includes protection technique “ia.”(B) Class I, Zone 1.

(1) General. In Class I, Zone 1 locations, the wiring methods in (B)(1)(a) through (B)(1)(f)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 and supervision

ensure that only qualified persons service the installation, and where the cable is not subject to physical damage, TypeMC-HL cable listed for use in Class I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugatedmetallic sheath, an overall jacket of suitable polymeric material, a separate equipment grounding conductor(s) inaccordance with 250.122, terminated with fittings listed for the application.(c) In industrial establishments with restricted public access, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation, and where the cable is not subject to physical damage, TypeITC-HL cable, listed for use in Class I, Zone 1 or Division 1 locations, with a gas/vaportight continuous corrugatedmetallic sheath, an overall jacket of suitable polymeric material and provided with termination fittings listed for theapplication. Type ITC-HL cable shall be installed in accordance with the provisions or 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 cable shall 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 envelope a minimum of

50 mm (2 in.) thick and provided with not less than 600 mm (24 in.) of cover measured from the top of the conduit tograde. Threaded rigid metal conduit or threaded steel intermediate metal conduit shall be used for the last 600 mm (24in.) of the underground run to emergence or to the point of connection to the aboveground raceway. An equipmentgrounding conductor shall be included to provide for electrical continuity of the raceway system and for grounding ofnon–current-carrying metal parts.Informational Note: For entry into enclosures required to be flameproof, explosionproof, or increased safety, see further

information on construction, testing and marking of cables, flameproof and increased safety cable fittings, andflameproof and increased safety cord connectors, In ANSI/UL 2225-2011, Cables and Cable-Fittings for Use inHazardous (Classified) Locations.

(2) Flexible Connections. Where necessary to employ flexible connections, flexible fittings listed for Class I,Zone 1 or Division 1 locations or flexible cord in accordance with the provisions of 505.17 terminated with a listed cordconnector that maintains the type of protection of the terminal compartment, shall be permitted.Informational Note: For entry into enclosures required to be flameproof, explosionproof, or increased safety, see further

information on construction, testing and marking of cables, flameproof and increased safety cable fittings, andflameproof and increased safety cord connectors, In ANSI/UL 2225-2011, Cables and Cable-Fittings for Use inHazardous (Classified) Locations.(C) Class I, Zone 2.

(1) General. In Class I, Zone 2 locations, the following wiring methods shall be permitted.(a) All wiring methods permitted by 505.15(B).(b) Types MC, MV, or TC cable, including installation in cable tray systems. The cable shall be terminated with listed

fittings. Single conductor Type MV cables shall be shielded or metallic-armored.(c) Type ITC and Type ITC-ER cable as permitted in 727.4 and terminated with listed fittings.(d) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, including installation in cable

tray systems. The cable shall be terminated with listed fittings.(e) Enclosed gasketed busways, enclosed gasketed wireways.(f) In industrial establishments with restricted public access where the conditions of maintenance and supervision

ensure that only qualified persons service the installation and where metallic conduit does not provide sufficientcorrosion resistance, listed reinforced thermosetting resin conduit (RTRC), factory elbows, and associated fittings, allmarked with the suffix -XW, and Schedule 80 PVC conduit, factory elbows, and associated fittings shall be permitted.Where seals are required for boundary conditions as defined in 505.16(C)(1)(b), the Zone 1 wiring method shall extend

100Printed on 1/23/2012

Report on Proposals – June 2013 NFPA 70into the Zone 2 area to the seal, which shall be located on the Zone 2 side of the Zone 1–Zone 2 boundary.(g) Intrinsic safety type of protection “ic” shall be permitted using any of the wiring methods permitted for unclassified

locations. Intrinsic safety type of protection “ic” systems shall be installed in accordance with the control drawing(s).Simple apparatus, not shown on the control drawing, shall be permitted in an intrinsic safety type of protection “ic”circuit, provided the simple apparatus does not interconnect the intrinsic safety type of protection “ic” system to anyother circuit.Informational Note: Simple apparatus is defined in 504.2.Separate intrinsic safety type of protection “ic” systems shall be installed in accordance with one of the following:(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 minimum thickness of 0.25

mm (0.01 in.)(2) Flexible Connections. Where provision must be made for limited flexibility, flexible metal fittings, flexible metal

conduit with listed fittings, liquidtight flexible metal conduit with listed fittings, liquidtight flexible nonmetallic conduit withlisted fittings, or flexible cord in accordance with the provisions of 505.17 terminated with a listed cord connector thatmaintains the type of protection of the terminal compartment shall be permitted.Informational Note: See 505.25(B) for grounding requirements where flexible conduit is used.

The revised text addresses the intent of the proposal.Reject the inclusion of the proposed Informational Note in 505.15(C)(1) as these wiring methods permit the use of

“listed” fittings. These fittings are not required to be “listed for the application” (location) and therefore reference toANSI/UL 2225 is not appropriate. UL 2225 does not contain ordinary location fittings in its scope. The publication dateof the standard was added in accordance with 3.3.7.4 of the Regulations Governing Committee Projects.

_______________________________________________________________________________________________14-161 Log #1436 NEC-P14


Revise text to read as follows:Wiring methods shall maintain the integrity of protection techniques and shall comply with

505.15(A) through (C).In Class I, Zone 0 locations, only intrinsically safe wiring methods in accordance with Article 504

shall be permitted.Informational Note: Article 504 only includes protection technique “ia.”

Article 504 was initially written to address the wiring methods for Division 1 and has not beensignificantly altered for intrinsic safety “ia”. The wiring methods for “ia” are referred to Article 504 from Articles 505 and506. In addition to this the wiring methods for “ib” should be identical to those for “ia”. There is a companion proposal toaddress wiring for intrinsic safety “ib”.

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(A) Class I, Zone 0. In Class I, Zone 0 locations, only intrinsically safe wiring methods in accordance with Article 504shall be permitted.Informational Note: Article 504 only includes protection technique “ia.”

Intrinsic safety type of protection “ib” shall be permitted using the wiring methods specified in Article 504.Intrinsic safety type of protection ‘ib’ should not have different installation requirements from those of

intrinsically safe type of protection ‘ia’. No specific requirements were for the wiring for type of protection “ib” wereincluded in the 2011 edition of the Code. The field wiring and terminal separation requirements between i.s. and non-i.s.wiring and between i.s and i.s. wiring in the product standards ANSI/ISA-60079-11 and ANSI/UL 913 for type ofprotection ‘ia’ and ‘ib’ are identical.The information note in 505.15(A) would be deleted as this would no longer be a true statement.

The panel notes that, in 505.15(B)(1), the mention of (B)(1)(f) should be changed editorially to(B)(1)(g).

_______________________________________________________________________________________________14-163 Log #2613 NEC-P14


Add new text to read as follows:(g) Fiber Optic cables of the types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall be permitted to

be installed in raceways as stated in 505.15(B). These Fiber Optic cables shall be sealed in accordance with 505.16.These proposals are a result of an ad-hoc task team consisting of members of CMP3, CMP14, and



102Printed on 1/23/2012



Modify existing text.(1) General. In Class I, zone 1 locations, the wiring methods in B(1)(a) through (B)(1)(f)(g) shall be permitted.Add new text.(g) In industrial establishments with restricted public access, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation, and where the cable is not subject to physical damageTypeTC-HL Cable, that complies with the crush and impact requirements of Type MC-HL cable and is identified for such usewith the marking, a separate equipment grounding conductor(s) in accordance with 250.122, and terminated with fittingslisted for the application. Type armored TC-HL cable, shall be installed in accordance with the provisions TC-HL cablefound in Article 336.


vibration caused by pumps and flow through the lines, so flexibility better than that provided by MC-HL cable or MI cableis needed. NEC 330.30(B) requires MC (thus MC-HL) cable to be supported within 12 inches of cable termination whencable has 4 or fewer conductors no larger than 10awg, which is often very difficult to provide support at line mounteddevices.While extra hard usage cord is permitted where flexible connection is required, the extra hard usage cord is not

available in configurations with shielded pairs or triads or for controls connections to valves and other devices. So aflexible cable type is necessary that will satisfy the needs for instrumentation and control.

MC-HL has severe requirements imposed as it can be installed outside of cable tray, and as “not continuouslysupported”. If braided armor TC-HL cable is installed, generally, in cable tray and otherwise continuously supported,with up to 6 ft unsupported between cable tray and utilization equipment it would be well protected for its length andexposed no more than would extra hard usage cord.Permitting braided armor TC-HL cable would not decrease the safety of Class I, Zone 1 electrical installations and

would enhance the maintainability, simply some installations, reduce risk of damage to cables during work around withinthe facilities where it is used.Companion proposals for addition of TC-HL in Article 336 have been submitted by this author.

As TC-HL cable is not an identified wiring method permitted in the Code, Panel 14 recommends amulti-Panel task group, to include Panel 6 and/or Panel 7, to address the submitter's concerns. The substantiationidentifies cable of smaller conductor size, but the proposed language does not limit the conductor size. The wording ofthe proposal is confusing with respect to whether the cable is armored or not. The proposal uses "identified" cabletypes, when they should be "listed".

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Modify existing text.(1) General. In Class I, zone 1 locations, the wiring methods in B(1)(a) through (B)(1)(f)(g) shall be permitted.Add new text.(g) In industrial establishments with restricted public access, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation, and where the cable is not subject to physical damage,Shipboard Cable with braided metallic armor, that complies with the crush and impact requirements of Type MC-HLcable and is identified for such use with the marking, a separate equipment grounding conductor(s) in accordance with250.122, and terminated with fittings listed for the application. Braided armor Shipboard cable, shall be installed inaccordance with the provisions for TC-ER cable found in Article 336.


vibration caused by pumps and flow through the lines, so flexibility better than that provided by MC-HL cable or MI cableis needed. NEC 330.30(B) requires MC (thus MC-HL) cable to be supported within 12 inches of cable termination whencable has 4 or fewer conductors no larger than 10awg, which is often very difficult to provide support at line mounteddevices.While extra hard usage cord is permitted where flexible connection is required, the extra hard usage cord is not

available in configurations with shielded pairs or triads or for controls connections to valves and other devices. So aflexible cable type is necessary that will satisfy the needs for instrumentation and control.

MC-HL has severe requirements imposed as it can be installed outside of cable tray, and as “not continuouslysupported”. If braided armor TC-HL cable is installed, generally, in cable tray and otherwise continuously supported,with up to 6 ft unsupported between cable tray and utilization equipment it would be well protected for its length andexposed no more than would extra hard usage cord.Permitting braided armor TC-HL cable would not decrease the safety of Class I, Zone 1 electrical installations and

would enhance the maintainability, simply some installations, reduce risk of damage to cables during work around withinthe facilities where it is used.

Braided armor shipboard cable is not a wiring method that is permitted in Chapter 3. Thesubstantiation identifies cable of smaller conductor size, but the proposed language does not limit the conductor size.The wording of the proposal is confusing with respect to marking.Code-Making Panel 14 recommends a multi-panel task group, to include members from Code-Making Panel 6 and/or

Code-Making Panel 7, to address the submitter's concerns.

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In 505.15(B)(2), revise the reference to 505.17 to 505.17(A).This will correlate with Panel Action on Proposal 14-180, as the newly created 505.17(B) only applies

to Zone 2 installations.

_______________________________________________________________________________________________14-166 Log #2797 NEC-P14



Where provision must be made for limited flexibility, flexible metal fittings, flexible metalconduit (FMC) with listed fittings, liquidtight flexible metal conduit with listed fittings, liquidtight flexible nonmetallicconduit with listed fittings, or flexible cord in accordance with the provisions of 505.17 terminated with a listed cordconnector that maintains the type of protection of the terminal compartment shall be permitted.Informational Note: See 505.25(B) for grounding requirements where flexible conduit (FMC) is used.

Flexible metal conduit (FMC) and liquidtight flexible metal conduitshall include an equipment bonding jumper of the wire type in compliance with 250.




_______________________________________________________________________________________________14-167 Log #2427 NEC-P14



(f) In industrial establishments with restricted public access, where the conditions of maintenance and supervisionensure that only qualified persons service the installation, and where metallic conduit (RMC) does not provide sufficientcorrosion resistance, listed reinforced thermosetting resin conduit (RTRC), factory elbows, and associated fittings, allmarked with the suffix -XW, and Schedule 80 PVC conduit, factory elbows, and associated fittings shall be permitted.Where seals are required for boundary conditions as defined in 505.16(C)(1)(b), the Zone 1 wiring method shall extendinto the Zone 2 area to the seal, which shall be located on the Zone 2 side of the Zone 1–Zone 2 boundary.


and more reliable.


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In Class I, Zone 2 locations, the following wiring methods shall be permitted.(a) All wiring methods permitted by 505.15(B).(b) Types MC, MV, TC or TC-ER cable, including installation in cable tray systems. The cable shall be terminated with

listed fittings. Single conductor Type MV cables shall beshielded or metallic-armored.

Add Type TC-ER cable. Other Extended Run cable constructions are currently permitted. TypePLTC-ER, Type ITC-ER and Type TC-ER are all built to the same requirements.

_______________________________________________________________________________________________14-169 Log #2614 NEC-P14


Add new text to read as follows:(h) Fiber Optic cables of the types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG, OFN, and OFC shall be permitted to

be installed in cable trays or any other raceway as stated in 505.15(C). Fiber Optic cables shall be sealed in accordancewith 505.16.



_______________________________________________________________________________________________14-169a Log #CP1405 NEC-P14


In 505.15(C)(2), delete the word "limited" in the first sentence and add a new exception to read:Exception: For elevator use, an identified elevator cable, type EO, ETP, or ETT, and as shown under the “use” column

in Table 400.4 for “Hazardous (classified) locations” and terminated with listed connectors that maintain the type ofprotection of the terminal compartment shall be permitted.

The word “limited” is deleted to remove ambiguity in the current language.Proposal 6-88 correctly identifies a situation where elevator cables are shown in Table 400.4 for “hazardous (classified)

locations”, but the wiring method is not currently permitted in Chapter 5. The Panel agrees with the submitter'ssubstantiation in Proposal 6-88, however the Panel disagrees that it justifies removal of their use in hazardous(classified) locations. This proposal addresses the submitter’s substantiation and corrects this correlation problem inChapter 5.

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Where provision must be made for limited flexibility, flexible metal fittings, flexible metalconduit with listed fittings, liquidtight flexible metal conduit (LFMC) with listed fittings, liquidtight flexible nonmetallicconduit with listed fittings, or flexible cord in accordance with the provisions of 505.17 terminated with a listed cordconnector that maintains the type of protection of the terminal compartment shall be permitted.Informational Note: See 505.25(B) for grounding requirements where flexible conduit (LFMC) is used.

Flexible metal conduit and liquidtight flexible metal conduit (LFMC)shall include an equipment bonding jumper of the wire type in compliance with 250.102.505.15(C)




_______________________________________________________________________________________________14-171 Log #2856 NEC-P14



Where provision must be made for limited flexibility, flexible metal fittings, flexible metalconduit with listed fittings, liquidtight flexible metal conduit with listed fittings, liquidtight flexible nonmetallic conduit(LFNC) with listed fittings, or flexible cord in accordance with the provisions of 505.17 terminated with a listed cordconnector that maintains the type of protection of the terminal compartment shall be permitted.




107Printed on 1/23/2012



Revise text to read as follows:Conduits containing cables with a gas/vaportight continuous

sheath capable of transmitting gases or vapors through the cable core shall be sealed in the Zone 1 location afterremoving the jacket and any other coverings so that the sealing compound surrounds each individual insulatedconductor (or optical fiber tube) and the outer jacket.



Revise text to read as follows:Conduits containing cables with a gas/vaportight continuous

sheath capable of transmitting gases or vapors through the cable core shall be sealed in the Zone 1 location afterremoving the jacket and any other coverings so that the sealing compound surrounds each individual insulatedconductor or optical fiber tube and the outer jacket.

The added text has been editorially revised by removing unnecessary parentheses.

_______________________________________________________________________________________________14-173 Log #2616 NEC-P14


Revise text to read as follows:Each multiconductor or optical multifiber cable in conduit

shall be considered as a single conductor or single optical fiber tube if the cable is incapable of transmitting gases orvapors through the cable core. These cables shall be sealed in accordance with 505.16(D).



108Printed on 1/23/2012



Revise text to read as follows:(a) Cables entering enclosures required to be flameproof or

explosionproof shall be sealed at the point of entrance. The seal shall comply with 505.16(D). Multiconductor or opticalmultifiber cables with a gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable coreshall be sealed in the Zone 2 location after removing the jacket and any other coverings so that the sealing compoundsurrounds each individual insulated conductor or optical fiber tube in such a manner as to minimize the passage ofgases and vapors. Multiconductor or optical multifiber cables in conduit shall be sealed as described in 505.16(B)(4).



109Printed on 1/23/2012



Revise text to read as follows:Informational Note No. 1: For further information on construction, testing, and marking requirements for conduit cable

sealing fittings, see ANSI/UL 1203,. ANSI/UL 2225, Cable and

Cable-Fittings for Use in Hazardous (Classified) Locations.Revise the Informational Note to reference the ANSI standard for cable sealing fittings in place of the

standard for conduit fittings.

Revise 505.16(C)(2) to read:(2) Cable Seals. Cable seals shall be located in accordance with (C)(2)(a), (C)(2)(b), and(C)(2)(c).

(a) Explosionproof and Flameproof Enclosures. Cables entering enclosures required to be flameproof orexplosionproof shall be sealed at the point of entrance. The seal shall comply with 505.16(D). Multiconductor cables witha gas/vaportight continuous sheath capable of transmitting gases or vapors through the cable core shall be sealed in theZone 2 location after removing the jacket and any other coverings so that the sealing compound surrounds eachindividual insulated conductor in such a manner as to minimize the passage of gases and vapors. Multiconductor cablesin conduit shall be sealed as described in 505.16(B)(4).Exception No. 1: Cables passing from an enclosure or room that is unclassified as a result of Type Z pressurization

into a Zone 2 location shall not require a seal at the boundary.Exception No. 2: Shielded cables and twisted pair cables shall not require the removal of the shielding material or

separation of the twisted pairs, provided the termination is by an approved means to minimize the entrance of gases orvapors and prevent propagation of flame into the cable core.(b) Cables That Will Not Transmit Gases or Vapors. Cables with a gas/vaportight continuous sheath and that will not

transmit gases or vapors through the cable core in excess of the quantity permitted for seal fittings shall not be requiredto be sealed except as required in 505.16(C)(2)(a). The minimum length of such cable run shall not be less than thelength that limits gas or vapor flow through the cable core to the rate permitted for seal fittings [200 cm3/hr (0.007 ft3/hr)of air at a pressure of 1500 pascals (6 in. of water)].Informational Note No. 1: For further information on construction, testing, and marking requirements for conduit sealing

fittings, see ANSI/UL 1203, Explosionproof and Dust-Ignition-Proof Electrical Equipment for Use in Hazardous(Classified) Locations.Informational Note No. 1: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see ANSI/UL 2225-2011, Cables and Cable-Fittings for Use in Hazardous (Classified) Locations.Informational Note No. 2: The cable core does not include the interstices of the conductor strands.

The date of the publication has been added in accordance with 3.3.7.4 of the Rules GoverningCommittee Projects and the ANSI designation was added.

Location of the text was moved to the relevant sections.

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Revise text to read as follows:The cross-sectional area of the conductors or optical fibers permitted in a seal

shall not exceed 25 percent of the cross-sectional area of a rigid metal conduit of the same trade size unless it isspecifically listed for a higher percentage of fill.



Revise text to read as follows:The cross-sectional area of the conductors or optical fiber tubes (metallic or

nonmetallic) permitted in a seal shall not exceed 25 percent of the cross-sectional area of a rigid metal conduit of thesame trade size unless it is specifically listed for a higher percentage of fill.

The added text has been revised to indicate that the cross-sectional area of the optical fiber tube isto be used, not that of the optical fibers themselves.

_______________________________________________________________________________________________14-177 Log #2691 NEC-P14


Revise text to read as follows:Where the authority having jurisdiction judges that there is a probability that liquid or condensed vapor may accumulate

within motors or generators, joints and conduit systems shall be arranged to minimize entrance of liquid. If means toprevent accumulation or to permit periodic draining are judged necessary, such means shall be provided at the time ofmanufacture and shall be considered an integral part of the machine.

As 90.4 gives the AHJ authority to exercise judgement in application of the code, the struck-throughtext is redundant and unnecessary. The format of the revised text is consistent with that used in Section 505.18(B).

_______________________________________________________________________________________________14-178 Log #2347 NEC-P14


Revise text to read as follows:5 A flexible cord shall be permitted for connection between portable

lighting equipment or other portable utilization equipment and the fixed portion of their supply circuit. flexible cord shallalso be permitted for that 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 industrial establishment whereconditions of maintenance and engineering supervision ensure that only qualified persons install and service theinstallation, and the flexible cord is protected by location or by a suitable guard from damage.

The above NEC section pertains to both Zone 1 and 2. However, the referenced NEC section,505.15(B) only pertains to Zone 1. This proposal incorporates a reference to 505.15(C) which pertains to Zone 2.

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Add new text to read as follows:To facilitate replacements, process control instruments shall be permitted to be connected

through flexible cord or cable, attachment plug, and receptacle, provided all of the following conditions apply:(1) Mating plug fastened to enclosure maintains both the degree of ingress protection and method of explosion

protection.(2) Plug is suitable for connection to extra hard usage cord, or cables permitted in 505.15(C) (eg TC, ITC, PLTC )

appropriate for the application.(3) Be of a locking type or otherwise require a tool to allow disconnection of plug from mating receptacle

The use of flexible cords as permitted in 505.17 is primarily applicable to power supply connections topower utilization equipment. Process control instruments and devices require conductor configurations (eq shieldedpairs and traids), that are not available in extra hard usage cord configurations. Process control instruments anddevices are generally more subject to removal and replacement than other equipments, so plug and receptacleconnection provide means to maintain electrical installations intact during work around activities in a facility. Therecurrently little guidance within NFPA 70 on the use of plug and receptacle application that can be applied to thenon-power applications.

See panel action on Proposal 14-180.The action on Proposal 14-180 meets the intent of this proposal.

112Printed on 1/23/2012


_______________________________________________________________________________________________Robert L. Seitz, Artech Engineering / Rep. ISA

Add new textTo facilitate replacements, process control instruments shall be permitted to be connected by

instrument or control cable, attachment plug, and receptacle, provided all of the following conditions apply:(1) A switch complying with 501.105(B)(1) is provided so that the attachment plug is not depended on to interrupt

current. The switch is not required if the circuit is non incendive.(2) The current does not exceed 3 amperes at 120 volts, nominal.(3) The instrument or control cable is a Type TC cable or is an ITC cable permitted in 505.15(C) of this Code and is

supplied through an attachment plug and receptacle of the locking and grounding type.(4) Only necessary receptacles are provided.(5) The receptacle carries a label warning against unplugging under load and a tool is required to allow the receptacle

to be unplugged.

The use of flexible cords as permitted in 505.17 is primarily applicable to power supply connections topower utilization equipment. Process control instruments and devices require conductor configurations (eq shieldedpairs and triads), that are not available in extra hard usage cord configurations. Process control instruments anddevices are generally more subject to removal and replacement than other equipments, so plug and receptacleconnection provide means to maintain electrical installations intact during work around activities in a facility. Therecurrently little guidance within NFPA 70 on the use of plug and receptacle application that can be applied to thenon-power applications.This proposal facilitates the ability for process instruments be properly replaced as this portion of Code originallyintended. The extra hard usage cord is not configured with the shielding and shield drain wires to permit proper wiringall the way to the field device or instrument. Permitting approved connectors to be installed on cables that are alreadypermitted as wiring methods should be a natural technological progression that will enhance the more sophisticatedautomation and control systems that process facilities are adopting.Improved connect ability can only enhance the safety of a facility as preterminated connectors will always have the

proper pin configurations when reconnected, the stripped ends of the conductors will not become frayed and theinsulation of the conductors will not be damaged.

Renumber and retitle 505.17 as follows:505.17 Flexible Cords and Connections505.17(A) Flexible Cords, Class I, Zones 1 and 2All existing text from 505.17 is moved to new 505.17(A), without change.Add a new 505.17(B) to read:505.17(B) Instrumentation Connections for Zone 2. To facilitate replacements, process control instruments shall be

permitted to be connected through flexible cord, attachment plug, and receptacle, provided all of the following conditionsapply:(1) A switch identified for Zone 2 is provided so that the attachment plug is not depended on to interrupt current, unless

the circuit is type of protection "ia, ib, or ic" then the switch is not required .(2) The current does not exceed 3 amperes at 120 volts, nominal.(3) The power-supply cord does not exceed 900 mm (3 ft), is of a type listed for extra-hard usage or for hard usage if

protected by location, and is supplied through an attachment plug and receptacle of the locking and grounding type.(4) Only necessary receptacles are provided.(5) The receptacle carries a label warning against unplugging under load.

The panel accepts that the text should appear in Article 505, similar to that in 501.105(B)(6). Thepanel does not accept the inclusion of "instrument or control cable", as it is not defined and, thus, is potentiallyunenforceable.Fixed wiring methods (Types TC and ITC) are not intended to be terminated with an attachment plug. Attachment

plugs are only permitted to be used with flexible cords, as currently stated in 400.7(B).

113Printed on 1/23/2012

Report on Proposals – June 2013 NFPA 70In (5), no substantiation was provided for the increase in the requirement.

_______________________________________________________________________________________________14-181 Log #1108 NEC-P14



IEEE Std. 1349-2011,


_______________________________________________________________________________________________14-182 Log #1065 NEC-P14




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Add a new paragraph to read as follows:Equipment marked with Group “IIC” is suitable for applications requiring Group IIA or Group IIB

equipment. Similarly, equipment marked with Group “IIB” is suitable for applications requiring Group IIA equipment.Equipment marked for a specific gas or vapor is suitable for applications requiring the suitability for that material.Informational Note: One common example combines these marking with the equipment marked “IIB +H2”, This

equipment is suitable for applications requiring Group IIA equipment, Group IIB equipment, or equipment for hydrogenatmospheres.Renumber existing (D) to (E).

Although clear in the product standards, it is not clear in Article 505 that IIC equipment is suitable forapplications requiring IIA or IIB equipment. Similarly, it is not clear that IIB equipment is suitable for applicationsrequiring IIA equipment. There is currently no text to address the suitability of equipment marked with the chemicalformula of a specific material.

Add a new paragraph to read as follows:Equipment marked with Group “IIC” shall be permitted for applications requiring Group IIA or Group IIB

equipment. Similarly, equipment marked with Group “IIB” shall be permitted for applications requiring Group IIAequipment.Equipment marked for a specific gas or vapor shall be permitted for applications where the specific gas or vapor may

be encountered.Informational Note: One common example combines these marking with the equipment marked “IIB +H2”, This

equipment is suitable for applications requiring Group IIA equipment, Group IIB equipment, or equipment for hydrogenatmospheres.Renumber existing (D) to (E).

The proposed text has been revised to replace the unenforceable phrase "is suitable".

_______________________________________________________________________________________________14-184 Log #668 NEC-P14


Revise text to read as follows:In a Class I, Zone 1 location, a multiwire branch circuit shall be permitted only if the

disconnect device opens all of the ungrounded circuit conductors simultaneously.As written, the current Code rule denies the use of any multiwire branch circuits. The exception allows

the use of them. Referencing the NEC Style Manual, 3.1.4 Exceptions. "It is the responsibility of the Code-Making Panelto determine whether the principle can be expressed most effectively as a separate positive code rule or as anexception to a rule." 3.1.4 also references Annex A, the first sentence of which states, "Exceptions should be re-writteninto positive language, if positive language achieves clarity." I ask that CMP 14 consider that this rule would express itsidea clearer if it were written as a permissive code rule instead of an exception. A companion proposal has beensubmitted for Section 501.40, 502.40 and 506.21.

Delete 505.21 entirely.The Code provision in 505.21 is covered in Chapter 2 [see 210.4(B)] and Chapters 1 through 4

apply to Chapter 5 except where the latter supersedes them. Deleting 505.21 satisfies the submitter’s intent.

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Add new text to read as follows:Informational Note: For reciprocating engine driven generators, compressors, and other loads installed in Class I Zone

2 locations, it is important to consider the risk of ignition of flammable materials associated with fuel, starting,compression, etc. that may be present due to inadvertent release or equipment malfunction by the engine ignitionsystem and controls. For further information on the requirements for ignition systems for reciprocating engines installedin Class I Zone 2 hazardous (classified) locations, see ANSI/ISA-12.20.01,

.Currently there are numerous installations of reciprocating engine prime movers (engines) driving

generators, compressors, pumps, and various other loads installed in Class I Zone 2 hazardous (classified) locations.These installations range from outdoor well ventilated areas within close proximity to production or process equipmentor in indoor locations that are adequately or inadequately ventilated handling flammable process, products, or fuel. Thecommonality between all these type installations is a natural gas fueled prime mover that utilizes a high voltage ignitionsystem.One specific example examined in detail: Ignition systems have been utilized on reciprocating engines driving natural

gas compressors in hazardous (classified) locations for many years. Operators of these compressor stations have onlyhad general guidance (NEC art 501, API RP 14F, local AHJ requirements) for proper source of ignition control for thesehazardous (classified) locations in the past. Conservative review of these general requirements led to the use ofshielded ignition systems where the primary high tension leads interconnecting the spark plugs for each power cylinderof the reciprocating engine to the ignition system were completely encased in grounded metallic sheathing materials toprevent any inadvertent arcs and sparks on the exterior of the ignition system that may lead to an ignition of a smallflammable gas leak or release associated with the gas compressor. These use of these shielded systems soon resultedin dielectric failures in the primary leads that resulted in ignition system miss-firing, miss-operations and engine damage.As these issues became more prevalent with compressor station operators, higher quality primary leads were developedbut were not able to resolve the high stresses associated with the shielded primary lead design. As most compressorstation buildings can be classified as Class I Zone 2, the use of explosion-proof or flame-proof protection techniques thatwere utilized in the shielded ignition systems design may not be required. Recognizing this, ISA 12 organized an effortto establish a fit for purpose performance standard that would employ Class I Zone 2 protection techniques utilizingnon-shielded technology for ignition systems in these applications. The ANSI/-ISA 12.20.01, General Requirements forElectrical Ignition Systems for Internal Combustion Engines in Class I, Division 2 or Zone 2, Hazardous (Classified)Locations, provides specific details and performance test procedures for non-shielded ignition systems for use in Class IZone 2 installations.

Add new text to read as follows:Informational Note: For reciprocating engine driven generators, compressors, and other equipment installed in Class I

Zone 2 locations, it is important to consider the risk of ignition of flammable materials associated with fuel, starting,compression, etc. that may be present due to inadvertent release or equipment malfunction by the engine ignitionsystem and controls. For further information on the requirements for ignition systems for reciprocating engines installedin Class I Zone 2 hazardous (classified) locations, see ANSI/ISA-12.20.01-2009,

.The panel has editorially revised the proposed text by changing the word "loads" in the first

sentence to "equipment" and by adding the publication date of 2009 to ANSI/ISA-12.20.01, in accordance with 3.3.7.4 ofthe Regulations Governing Committee Projects.

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Revise text to read as follows:Grounding and Bonding. Grounding and bonding shall comply with Article 250 and the requirements in

505.25(A) and (B).(A) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding

purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means ofbonding shall apply to all intervening raceways, fittings, boxes, enclosures, and so forth, between Class I locations andthe point of grounding for service equipment or point of grounding of a separately derived system.Exception: The specific bonding means shall be required only to the nearest point where the grounded circuit

conductor and the grounding electrode are connected together on the line side of the building or structure disconnectingmeans as specified in 250.32(B), provided the branchcircuit overcurrent protection is located on the load side of thedisconnecting means.

See 250.100 for additional bonding requirements in hazardous (classified) locations.(B) Types of Equipment Grounding Conductors. Flexible metal conduit and liquidtight flexible metal conduit shall

include an equipment bonding jumper of the wire typein compliance with 250.102.Exception: In Class I, Zone 2 locations, the bonding jumper shall be permitted to be deleted where all of the following

conditions are met:(a) Listed liquidtight flexible metal conduit 1.8 m (6 ft) or less in length, with fittings listed for grounding, is used.(b) Overcurrent protection in the circuit is limited to 10 amperes or less.(c) The load is not a power utilization load.Grounding and Bonding. Grounding and bonding shall comply with Article 250.Informational Note: See 250.100 for additional bonding requirements in hazardous (classified) locations.




_______________________________________________________________________________________________14-187 Log #2695 NEC-P14


Revise text to read as follows:Flexible metal conduit and liquidtight flexible metal conduit shall include an equipment bonding jumper of the wire type

in compliance with in accordance with 250.102.Revise text for clarity. Additionally, Section 250.102 does not specify ‘wire type’.


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Revise text to read as follows:Informational Note: ANSI/ISA-12.27.01-2003,

ANSI/ISA-12.27.01,


Revise the Informational Note to 505.26 to read: "Informational Note: For construction and testing requirements forprocess sealing for listed and marked “single seal” or “dual seal” requirements, refer to ANSI/ISA-12.27.01-2011,Requirements for Process Sealing Between Electrical Systems and Potentially Flammable or Combustible ProcessFluids.

Paragraph 3.3.7.4 of the Regulations Governing Committee Projects and 2.3.1.2.4 of the NFPAManual of Style require dated references to Standards. The publication date of 2011 is correct for this referenceddocument.

_______________________________________________________________________________________________14-189 Log #1989 NEC-P14



will be subjected to upon failure of the single process seal.Revise the Informative Note in this section as follows:Informative Note: For construction and testing requirements for process sealing for listed and marked “single seal”,or

“dual seal” or “secondary seal”equipment, requirements refer to ANSI/ISA-12.27.01, Requirements for Process SealingBetween Electrical Systems and Potentially Flammable or Combustible Process Fluids.

Requirements for an add-on secondary seal will be included in the next edition of ANSI/ISA-12.27.01.These seals have been examined and tested to ensure that they are adequate and reliable process seals and shouldbe allowed as an “additional means” in Section 505.26.Update the Informative Note to include “secondary seal”. Revise the title of ANSI/ISA-12.27.01.Refer to example drawing in ANSI/ISA-12.27.01.


will be subjected to upon failure of the single process seal.Revise the Informational Note in this section as follows:Informational Note: For construction and testing requirements for process sealing for listed and marked “single seal”,or

“dual seal” or “secondary seal”equipment, requirements refer to ANSI/ISA-12.27.01-2011, Requirements for ProcessSealing Between Electrical Systems and Potentially Flammable or Combustible Process Fluids.

The panel has changed the word "informative" to "informational" and has added the publicationdate to the citation for ANSI/ISA-12.27.01, in accordance with 3.3.7.4 of the Regulations Governing Committee Projects.

118Printed on 1/23/2012


_______________________________________________________________________________________________David Wechsler, Lake Jackson, TX

Delete Article 506 and as applicable references to Article 506 in other sections of the NEC.In May 2004, action was taken by Code Making Panel 14 to propose a new Article 506 as an optional

alternative to Article Nos. 500, 502 and 503 (See Log 14-108a (CP1409). A companion proposal Log 14-109, providedadditional clarification for Article 506, addressing that the Zone based classification system, Zone 20, Zone 21 and Zone22 for flammable dusts, fibers and flyings was introduced in Europe and that the US had participated in the IEC TC31harmonization.Since its introduction within each code cycle Article 506 has been modified to try and be current with the developing

IEC dust standards. The basic equipment design concept of Article 502 and Article 506 to keep the dust out of theenclosure remains a common method of protection attribute.Unfortunately, we again see that the IEC and the US have some very basic differences and in the light of recent

serious explosions involving combustible dusts greater focus on the US practice needs to be assured. Article 506 unlikeArticle 502 does not follow the US same treatment of dusts. For instance, Article 506 continues to define dust groups onthe basis of conductivity. This is a principle which the US NEC rejected some years ago. An attempt to provide aworkaround was to substitute the term metal dust for a conductive dust. However this only created another differencebetween the IEC and this Article 506. Article 506, unlike Article 502, does not clearly address carbonaceous dustscontaining more than 7% volatiles as Group F which again places US Industries using coal in having to decide whichapplication to follow for the same material. Article 506 continues to group materials which are addressed under Article503 as being the same as dusts, again creating another conflict between the code articles for the same given material.Work still is continuing in the IEC on dust issues and the IEC installation standards which formerly only dealt withflammable gases and vapors are today being merged with dust critiera creating some additional differences. Even thedefinition of a combustible dust, per NFPA 499, does not agree with that used in the IEC. These and other differencesdo not reflect the use of Article 506 as an optional alternative, but rather a conflicting standard. After the completion of 3code cycles we need to remove Article 506 and let the US follow the time tested requirements in Articles 500, 502 and503.

The substantiation does not justify removing Article 506 entirely without providing Code text thataddresses Zones 20, 21, and 22.

_______________________________________________________________________________________________14-190a Log #CP1416 NEC-P14


Revise 506.1 to read as follows:506.1 Scope. This article covers the requirements for the zone classification system as an alternative to the division

classification system covered in Article 500, Article 502, and Article 503 for electrical and electronic equipment andwiring for all voltages in Zone 20, Zone 21, and Zone 22 hazardous (classified) locations where fire and explosionhazards may exist due to combustible dusts or ignitible fibers/flyings. Combustible metallic dusts are not covered by therequirements of this article.

ANSI/ISA Standard 60079-0 - 2009 includes requirements for equipment in areas subject to metaldusts. The revision to the scope statement is necessary to conform with proposed changes to include dust groups inArticle 506.The panel understands that the scope statement is under the jurisdiction of the Technical Correlating Committee and

respectfully seeks support for this change.

119Printed on 1/23/2012



Revise text to read as follows:Informational Note 2.: ANSI/ISA-61241-10 (12.10.05)-2004,

ANSI/ISA-60079-10-2,


This proposal cannot be accepted because the document has not been published yet.

_______________________________________________________________________________________________14-192 Log #1223 NEC-P14


Revise text to read as follows: Apparatus in which the circuits are not necessarily nonincendive

themselves but that affect the energy in nonincendive field wiring circuits and are relied upon to maintain nonincendiveenergy levels. Associated nonincendive field wiring apparatus may be either 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

Associated nonincendive field wiring apparatus has designated associated nonincendive fieldwiring apparatus connections for nonincendive field wiring apparatus and may also have connections for other electricalapparatus.

: Associated nonincendive field wiring apparatus may be either 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


Paragraph 2.3.2.2 of the NFPA Manual of Style does not require definitions in the form of a singlesentence and this is not modified in the NEC Style Manual. The NFPA Manual of Style requires definitions in the form ofa single paragraph unit.

120Printed on 1/23/2012



In 506.2 replace the current definition of Combustible Dust with the following:Combustible Dust. Dust particles of 500 microns or smaller (material passing a U.S. No. 35 Standard Sieve as defined

in ASTM E 11, Standard Specification for Wire Cloth and Sieves for Testing Purposes) are considered to present a dustfire or dust explosion hazard unless determined otherwise. (See ASTM E 1226 or ISO 6184/1). [499:3.3.3]

Definition is extracted from NFPA 499 and the definition in the 2012 Edition of NFPA 499 has beenrevised.

_______________________________________________________________________________________________14-193 Log #1438 NEC-P14


Delete the following text:Nonincendive Circuit. A circuit, other than field wiring, in which any arc or thermal effect produced under intended

operating conditions of the equipment is not capable, under specified test conditions, of igniting the flammable gas–air,vapor–air, or dust–air mixture.Informational Note: Conditions are described in ANSI/ISA- 12.12.01-2007, Nonincendive Electrical Equipment for Use

in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations.Nonincendive Equipment. Equipment having electrical/ electronic circuitry that is incapable, under normal operating

conditions, of causing ignition of a specified flammable gas– air, vapor–air, or dust–air mixture due to arcing or thermalmeans.Informational Note: Conditions are described in ANSI/ISA- 12.12.01-2007, Nonincendive Electrical Equipment for Use

in Class I and II, Division2, and Class III, Divisions 1 and 2 Hazardous (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: Conditions are described in ANSI/ISA- 12.12.01-2007, Nonincendive Electrical Equipment for Use

in Class I and II, Division 2, and Class III, Divisions 1 and 2 Hazardous (Classified) Locations.The new editions of ISA 60079-11 (12.02.01) now includes the requirements for intrinsically safe

equipment for combustible dust atmospheres. This includes a third category “ic” which would be suitable for Zone 22.

121Printed on 1/23/2012



Revise text to read as follows:Nonincendive Circuit Informational Note: ANSI/ISA-12.12.01-2007,

ANSI/ISA-12.12.01,

Nonincendive Equipment Informational Note: ANSI/ISA-12.12.01-2007,ANSI/ISA-12.12.01,


ANSI/ISA-12.12.01,

Protection by Encapsulation “mD” Informational Note: ANSI/ISA-61241-18 (12.10.07)-2006,

ANSI/ISA-61241-18 (12.10.07),

Protection by Enclosure “tD” Informational Note: ANSI/ISA-61241-0 (12.10.02)-2006,, and ANSI/ISA-61241-1

(12.10.03)-2006,ANSI/ISA-61241-0 (12.10.02),

, and ANSI/ISA-61241-1 (12.10.03),


Revise text to read as follows:Nonincendive Circuit Informational Note: ANSI/ISA-12.12.01-2007,

ANSI/ISA-12.12.01-2011,

Nonincendive Equipment Informational Note: ANSI/ISA-12.12.01-2007,ANSI/ISA-12.12.01-2011,


ANSI/ISA-12.12.01-2011,

Protection by Encapsulation “mD” Informational Note: ANSI/ISA-61241-18 (12.10.07)-2006,

ANSI/ISA-61241-18 (12.10.07)-2011,

122Printed on 1/23/2012

Report on Proposals – June 2013 NFPA 70Protection by Enclosure “tD” Informational Note: ANSI/ISA-61241-0 (12.10.02)-2006,

, and ANSI/ISA-61241-1(12.10.03)-2006,

ANSI/ISA-61241-0 (12.10.02)-2011,, and ANSI/ISA-61241-1 (12.10.03)-2011,

Paragraph 3.3.7.4 of the Regulations Governing Committee Projects and 2.3.1.2.4 of the NFPAManual of Style require dated references to Standards. The publication date of 2011 is correct for these referenceddocuments. The titles have not changed, only the dates.

_______________________________________________________________________________________________14-195 Log #1224 NEC-P14


Revise text to read as follows: Wiring that enters or leaves an equipment enclosure and, under normal operating

conditions of the equipment, 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.

: Normal operation includes opening, shorting, or grounding the field wiring.The NFPA Manual of Style requires definitions to be in single sentences. The information provided in

the subsequent sentences is not really a part of the definition; it is further information that is best placed in aninformational note.


123Printed on 1/23/2012



Revise text to read as follows:Type of protection where electrical parts that could cause ignition of a mixture of

combustible dust or fibers/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),

, ANSI/UL 60079-18,, and ANSI/ISA-61241-18 (12.10.07)-2006,

.Informational Note No. 2: Encapsulation is designated level of protection “maD” or “ma”for use in Zone 20 locations.

Encapsulation is designated level of protection “mbD” or “mb” for use in Zone 21 locations. Encapsulation is designatedtype of protection “mc” for use in Zone 22 locations.

New editions of ANSI/ISA-60079-18 (12.23.01) and ANSI/UL 60079-18 now include three levels ofprotection by Encapsulation for explosive dust atmospheres. These three levels include an expansion of the previouslyavailable “ma” and “mb” to now be for use in Zone 20 and 21 locations, in addition to Class I, Zone 0 and Zone 1 areas,respectively. Also, a new level of protection “mc” for use in Zone 22 locations, in addition to Class I, Zone 2 locations, isnow included.For definition purposes, all types of encapsulation can be referred as Encapsulation “m”.

Accept the proposed amendments, but add the correct edition dates as follows:ANSI/ISA-60079-18 (12.23.01)-2009ANSI/UL 60079-18-2009ANSI/ISA-61241-18 (12.10.07)-2011

The appropriate edition dates have been added in accordance with Paragraph 3.3.7.4 of theRegulations Governing Committee Projects.

124Printed on 1/23/2012



Revise text to read as follows:Protection by Intrinsic Safety “iD.” Type of protection where any spark or thermal effect is incapable of causing ignition

of a mixture of combustible dust, fibers, or flyings in air under prescribed test conditions.Informational Note 1: For additional information, see ANSI/ISA-60079-11 (12.01.01)

ANSI/UL 60079-11,ANSI/ISA- 61241-11 (12.10.04),

Informational Note No. 2: Intrinsic safety is designated level of protection “iaD” or “ia” for use in Zone 20 locations.Intrinsic safety is designated level of protection “ibD” or “ib” for use in Zone 21 locations. Intrinsic safety is designatedtype of protection “ic” for use in Zone 22 locations.

The new edition of ISA 60079-11 (12.02.01) now include the requirements for intrinsically safeequipment for explosive dust atmospheres. The descriptive letters has been modified to delete the “D” to align with theother standards used for Zones.

Accept the proposed amendments verbatim, but add the correct date of 2011 to the references to ANSI/ISA-60079-11(12.01.01) and to ANSI/UL 60079-11, and the correct date of 2011 to the reference to ANSI/ISA- 61241-11 (12.10.04).Also, change the title to read: Protection by Intrinsic Safety “i”.

The appropriate dates have been added in accordance with the Regulations Governing CommitteeProjects.In the title, "iD" has been changed to "i" to correlate with Proposals 14-196 and 14-198.

_______________________________________________________________________________________________14-198 Log #1987 NEC-P14


Revise text to read as follows:Type of protection for explosive dust atmospheres where electrical apparatus is

provided with an enclosure providing dust ingress protection and a means to limit surface temperatures.Informational Note 1: For additional information, see ANSI/ISA-60079-31 (12.10.03)-2006,

ANSI/ISA-61241-0 (12.10.02)-2006,, and

ANSI/ISA-61241-1 (12.10.03)-2006,

Informational Note No. 2: Protection by Enclosure is designated level of protection “ta” for use in Zone 20 locations.Protection by Enclosure is designated level of protection “tb” or “tD” for use in Zone 21 locations. Protection byEnclosure is designated level of protection “tc” or “tD” for use in Zone 22 locations.

Revised Informational Note 2 reflects the latest product standards.

Accept the proposal verbatim, but add the date of 2009 for ANSI/ISA-60079-31 and 2011 for ANSI/ISA-61241-1(12.10.03).

The appropriate dates have been added in accordance with 3.3.7.4 of the Regulations GoverningCommittee Projects.

125Printed on 1/23/2012



Add text to read as follows:All other applicable rules contained in this shall apply to electrical equipment and wiring

installed in hazardous (classified) locations.

Article 506 at the present time does not require compliance with the general requirements for allequipment that are found in the other parts of the NEC. This proposal also correlates this Article with the samerequirement found in 500.3 and 505.3.

_______________________________________________________________________________________________14-200 Log #2018 NEC-P14


Revise text to read as follows:(B)(2) Zone 21 (d) Informational Note 1: ANSI/ISA-61241-10 (12.10.05)-2004,

ANSI/ISA-60079-10-2,

(3) Zone 22 (c) Informational Note 1: ANSI/ISA-61241-10 (12.10.05)-2004,

ANSI/ISA-60079-10-2,


The 2012 edition of the referenced document has not been published yet. Also, Paragraph 3.3.7.4of the Regulations Governing Committee Projects requires that referenced documents be identified with their publicationdates.

126Printed on 1/23/2012



Add a new 506.6 to read as follows:506.6 Material GroupsFor the purposes of testing, approval, and area classification, various air mixtures (not oxygen enriched) shall be

grouped as required in 506.6(A), (B), and (C).(A) Group IIIC Combustible metal dust

Informational Note 1 - Group IIIC is equivalent to Class II, Group E as described in 500.6.(B)(1).(B) Group IIIB Combustible dust other than combustible metal dust

Informational Note 2 - Group IIIB is equivalent to Class II, Groups F and G as described in 500.6(B)(2) and 500.6(B)(3),respectively.(C) Group IIIA Solid particles, including fibers, greater than 500 µm in nominal size which may be suspended in air and

could settle out of the atmosphere under their own weightInformational Note 3- Group IIIA is equivalent to Class III.Informational Note 4 - Examples of flyings include rayon, cotton (including cotton linters and cotton waste), sisal, jute,

hemp, cocoa fiber, oakum, and baled waste kapok.Renumber existing 506.6 Special Precaution as 506.7

Product standards include a marking of the dust group. Inclusion of the dust groups in Article 506 isnecessary to properly select and apply the equipment currently manufactured.

_______________________________________________________________________________________________14-201 Log #1440 NEC-P14


Delete the following text:This protection technique shall be permitted for equipment in Zone 22 locations for which it

is identified.The new edition of ISA 60079-11 (12.02.01) now include the requirements for intrinsically safe

equipment for combustible dust atmospheres. This includes a third category “ic” which would be suitable for Zone 22.

_______________________________________________________________________________________________14-202 Log #1441 NEC-P14


Revise text to read as follows:This protection technique shall be permitted for equipment in Zone 20, Zone 21, and Zone 22

locations for which it is identified. Installation of intrinsically safe apparatus and wiring shall be in accordance with therequirements of Article 504.

Section 506.8 addresses Protection Techniques. Section 506.15 addresses Wiring Methods. Acompanion proposal has been made separately to address 506.15 for intrinsically safe apparatus.

127Printed on 1/23/2012



Revise text to read as follows:This protection technique shall be permitted for equipment in Zone 20, Zone

21, and Zone 22 locations for which it is identified.Informational Note: See Table 506.9(C)(2)(3) for the descriptions of subdivisions for encapsulation.

New editions of ANSI/ISA-60079-18 (12.23.01) and ANSI/UL 60079-18 now include three levels ofprotection by Encapsulation for explosive dust atmospheres. These three levels include an expansion of the previouslyavailable “ma” and “mb” to now be for use in Zone 20 and 21 locations, in addition to Class I, Zone 0 and Zone 1 areas,respectively. Also, a new level of protection “mc” for use in Zone 22 locations, in addition to Class I, Zone 2 locations, isnow included.For definition purposes, all types of encapsulation can be referred as Encapsulation “m”.

_______________________________________________________________________________________________14-204 Log #2006 NEC-P14


Revise text to read as follows:This protection technique shall be permitted for equipment in Zone 20,

Zone 21 and Zone 22 locations for which it is identified.Informational Note: See Table 506.9(C)(2)(3) for the descriptions of subdivisions for Protection by Enclosure “t”.

Currently the U.S. requirements for are specified in ANSI/ISA-60079-31 andANSI/ISA-61241-1 which have slightly different marking designations. For simplification, all types of Protection byEnclosure can be referred as simply with the marking and location designations specified inTable 506.9(C)(2)(3).

_______________________________________________________________________________________________14-204a Log #CP1419 NEC-P14


In 506.9(C)(1), add to read as follows:(2) Material Group in accordance with 506.6Renumber existing (2) to (3)


128Printed on 1/23/2012



Revise to read as follows:506.9(C)(1)(2) Temperature classification Maximum surface temperature in accordance with 506.9(D), marked as a

temperature value, in degrees C, preceded by “T” and followed by the symbol “°C”.506.9(C)(2)(4) Temperature classification Maximum surface temperature in accordance with 506.9(D), marked as a

temperature value, in degrees C, preceded by “T” and followed by the symbol “°C”.506.9(D) Equipment shall be marked to show the operating maximum surface

temperature referenced to a 40°C (104°F) ambient, or at the higher marked ambient temperature if the equipment israted and marked for an ambient temperature of greater than 40°C. Electrical equipment designed for use in theambient temperature range between -20°C and +40°C shall require no additional ambient temperature marking.Electrical equipment that is designed for use in a range of ambient temperatures other than −20°C and +40°C isconsidered to be special; and the ambient temperature range shall then be marked on the equipment, including eitherthe symbol “Ta” or “Tamb” together with the special range of ambient temperatures. As an example, such a markingmight be “–30°C ≤ Ta ≤ +40°C.”Electrical equipment suitable for ambient temperatures exceeding 40°C (104°F) shall bemarked with both the maximum ambient temperature and the operating temperature at that ambient temperature.Informational Note: As an example, such a marking might be “–30°C ≤ Ta ≤ +40°C.”

The wording on 506.9(D) is not consistent with that of 506.9(C) and leads to confusion as theterminology and presentation differs slightly from that used in the product standards.Wording aligned with that of 505.9(D), including the deletion of the Fahrenheit values and the relocation of the exampleto an Informational Note.

_______________________________________________________________________________________________14-205a Log #CP1420 NEC-P14


In 506.9(C)(2), add to read as follows:(4) Material Group per 506.6Renumber existing (4) and (5) to (5) and (6), respectively.


129Printed on 1/23/2012



Revise table as follows:

***INSERT TABLE 70_L1442_TB506-9(C)(2)(3)_R HERE***

The new editions of ISA 60079-11 (12.02.01) now includes the requirements for intrinsically safeequipment for explosive dust atmospheres. This new version of the standard includes a third level ‘ic’ which did not existin the previous standard ANSI/ISA 61241-11.

The Panel accepts the addition of the new table entries for Types ic and [ic]. The rest of the table remains unchanged.The Panel notes that the revised table, as submitted is incomplete. Other methods of protection

are retained.

_______________________________________________________________________________________________14-207 Log #1994 NEC-P14




New editions of ANSI/ISA-60079-18 (12.23.01) and ANSI/UL 60079-18 now include three levels ofprotection by Encapsulation for explosive dust atmospheres. These three levels include an expansion of the previouslyavailable “ma” and “mb” to now be for use in Zone 20 and 21 locations, in addition to Class I, Zone 0 and Zone 1 areas,respectively. Also, a new level of protection “mc” for use in Zone 22 locations, in addition to Class I, Zone 2 locations, isnow included.

The Panel accepts the addition of the new table entry for Type mc. The rest of the table remains unchanged.The panel notes that the revised table, as submitted is incomplete. Other methods of protection are

retained.

130Printed on 1/23/2012



Revise text to read as follows:ta Protection by enclosures 21 20

Level of Protection “ta” is suitable for Zone 20, not limited to Zone 21 as shown.

Code-Make Panel 14 understands that the reference is to Table 506.9(C)(2)(3).

_______________________________________________________________________________________________14-209 Log #1445 NEC-P14


Revise to read as follows:(2) Zone Equipment. Equipment meeting one or more of the protection techniques described in 506.8 shall be marked

with the following in the order shown:(1) Zone(2) Symbol “AEx”(3) Protection technique(s) in accordance with Table 506.9(C)(2)(3)(4) Temperature classification, marked as a temperature value, in degrees C, preceded by T(5) Ambient temperature marking in accordance with 506.9(D)

AExAs associated intrinsically safe apparatus is not exposed to combustible dust a temperature

classification is not required. This is already addressed for gases in 505.9(B)(2) Exception 1.

_______________________________________________________________________________________________14-209a Log #CP1401 NEC-P14


In 506.9(D), delete the sentence “As an example, such a marking might be “–30°C ≤ Ta ≤ +40°C.”from the mandatory text and add the text as an Informational Note to 506.9(D).

Examples of an application are informational, as they cannot be enforced.

131Printed on 1/23/2012



Revise text to read as follows:Equipment shall be marked to show the operating temperature referenced to a 40°C

(104°F) ambient. For equipment installed in a Zone 20 or 21 location, the operating temperature shall be based onoperation of the equipment when blanketed with dust or fibers/flyings. Electrical equipment designed for use in theambient temperature range between -20°C and +40°C shall require no additional ambient temperature marking.Electrical equipment that is designed for use in a range of ambient temperatures other than -20°C and +40°C isconsidered to be special; and the ambient temperature range shall then be marked on the equipment, including eitherthe symbol “Ta” or “Tamb” together with the special range of ambient temperatures.As an example, such a marking might be “–30°C = Ta = +40°C.” Electrical equipment suitable for ambient temperaturesexceeding 40°C (104°F) shall be marked with both the maximum ambient temperature and the operating temperature atthat ambient temperature.

The current text is not clear as to if this temperature is based on operation of the equipment in free airor when the equipment is blanketed with dust or fibers/flyings. In a Zone 20 or 21 location, it would be expected that ablanket of dust or fibers/flyings would exist under normal operating conditions. Equipment temperatures under such ablanket will be considerably higher than in free air due to the insulating effect of the blanket and may very well exceedthe ignition temperature of the dust or fibers/flyings when in free air they would not. The ANSI standards for theequipment, ANSI/ISA-61241-1 for example, require the temperature be determined with a dust blanket.

Revise text to read as follows:Equipment shall be marked to show the operating temperature referenced to a 40°C

(104°F) ambient. For equipment installed in a Zone 20 or 21 location, the operating temperature shall be based onoperation of the equipment when blanketed with the maximum amount of dust (or with dust simulating fibers/flyings) thatcan accumulate on the equipment. Electrical equipment designed for use in the ambient temperature range between-20°C and +40°C shall require no additional ambient temperature marking. Electrical equipment that is designed for usein a range of ambient temperatures other than -20°C and +40°C is considered to be special; and the ambienttemperature range shall then be marked on the equipment, including either the symbol “Ta” or “Tamb” together with thespecial range of ambient temperatures.As an example, such a marking might be “–30°C = Ta = +40°C.” Electrical equipment suitable for ambient temperaturesexceeding 40°C (104°F) shall be marked with both the maximum ambient temperature and the operating temperature atthat ambient temperature.

The proposed text has been amended to provide a quantifiable measure of a blanket of dust or dustsimulating fibers/flyings.

132Printed on 1/23/2012



Revise text to read as follows:506.9(E)(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, or listed cable fittings shall be used.All remaining text stays the same.

This is a companion proposal to Section 500.8(E)(1) that was submitted for the 2011 Comment phase.The Comment action was to "Hold" till the 2014 Proposal phase. I had neglected to submit the same proposals toSection 505.9(E)(1) and 506.9(E)(1). The substantiation is similar.As 505.9(E)(1) is presented in the 2011 NEC, a grammatical error leaves the cable fittings without a rule that requires

them to be listed. Because of the comma, the word "listed" ahead of "listed conduit fittings" only applies to the conduitfittings. The addition of the word "listed" in front of cable fittings will add the listing requirement to the cable fittings.

The Panel accepts this proposal, with the understanding that the submitter meant to underline onlythe second instance of the word "listed" and not the first.

_______________________________________________________________________________________________14-212 Log #1443 NEC-P14


Add text to read as follows:Wiring methods shall maintain the integrity of the protection techniques and shall comply with

506.15(A), (B), or (C).In Zone 20 locations, the following wiring methods shall be permitted.

(1) Threaded rigid metal conduit or threaded steel intermediate metal conduit.(2) Type MI cable terminated with fittings listed for the location. Type MI cable shall be installed and supported in a

manner toavoid tensile stress at the termination fittings.

In Zone 21 locations, the wiring methods in (B)(1) and (B)(2) shall be permitted.(1) All wiring methods permitted in 506.15(A).(2) Fittings and boxes that are dusttight, provided with threaded bosses for connection to conduit, in which taps, joints,

or terminal connections are not made, and are not used in locations where metal dust is present, may be used.

The wiring methods permitted for intrinsically safe apparatus in explosive dust atmospheres classifiedunder the zone scheme are different from those permitted under the Division scheme. The wiring methods forintrinsically safe apparatus were previously addressed in 506.8 – Protection techniques.

Accept the submitter's proposed text, but replace "installed in accordance with" with "connected using".The text has been revised for clarity.

133Printed on 1/23/2012



Revise text to read as follows:Wiring methods shall maintain the integrity of the protection techniques and shall comply with

506.15(A), (B), or (C).In Zone 20 locations, the following wiring methods shall be permitted.

(1) Threaded rigid metal conduit or threaded steel intermediate metal conduit.(2) Type MI cable terminated with fittings listed for the location. Type MI cable shall be installed and supported in a

manner to avoid tensile stress at the termination fittings.

(3) In industrial establishments with limited public access, where the conditions of maintenance and supervision ensurethat only qualified persons service the installation, Type MC-HL cable listed for use in Zone 20 locations, with acontinuous corrugated metallic sheath, an overall jacket of suitable polymeric material, and a separate equipmentgrounding conductor(s) in accordance with 250.122, and terminated with fittings listed for the application, shall bepermitted. Type MC-HL cable shall be installed in accordance with the provisions of Article 330, Part II.

(4) In industrial establishments with restricted public access, where the conditions of maintenance and supervisionensure that only qualified persons service the installation, and where the cable is not subject to physical damage, TypeITC-HL cable listed for use in Zone 1 or Class I, Division 1 locations, with a gas/vaportight continuous corrugatedmetallic sheath and an overall jacket of suitable polymeric material, and terminated with fittings listed for the application.Type ITC-HL cable shall be installed in accordance with the provisions of Article 727.(5) Fittings and boxes shall be identified for use in Zone 20 locations.

(6) Where necessary to employ flexible connections, liquidtight flexible metal conduit with listed fittings, liquidtightflexible nonmetallic conduit with listed fittings, or flexible cord listed for extra-hard usage and provided with listed fittingsshall be used. Where flexible cords are used, they shall also comply with 506.17 and shall be terminated with a listedcord connector that maintains the type of protection of the terminal compartment. Where flexible connections are subjectto oil or other corrosive conditions, the insulation of the conductors shall be of a type listed for the condition or shall beprotected by means of a suitable sheath.

Informational Note: See 506.25 for grounding requirements where flexible conduit is used.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .In Zone 21 locations, the wiring methods in (B)(1) and (B)(2) shall be permitted.

(1) All wiring methods permitted in 506.15(A).(2) Fittings and boxes that are dusttight, provided with threaded bosses for connection to conduit, in which taps, joints,

or terminal connections are not made, and are not used in locations where metal dust is present, may be used.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.(4) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, including installation 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, MI, MV, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single

layer, with a space not less than the larger cable diameter between two adjacent cables, shall be the wiring methodemployed. Single-conductor Type MV cables shall be shielded or metallic armored.(7) Nonincendive field wiring shall be permitted using any of the wiring methods permitted for unclassified locations.

Nonincendive field wiring systems shall be installed in accordance with the control drawing(s). Simple apparatus, notshown on the control drawing, shall be permitted in a nonincendive field wiring circuit, provided the simple apparatusdoes not interconnect the nonincendive field wiring circuit to any other circuit.Informational Note 1: is defined in 504.2. Separation of nonincendive field wiring circuits shall be in

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Report on Proposals – June 2013 NFPA 70accordance with one of the following:a. Be in separate cablesb. Be in multiconductor cables where the conductors of each circuit are within a grounded metal shieldc. Be in multiconductor cables where the conductors have insulation with a minimum thickness of 0.25 mm (0.01 in.)Informational Note 2: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .(8) Boxes and fittings shall be dusttight.

Where necessary to protect the ingress of combustible dust or ignitible fibers/flyings, or to maintainthe type of protection, seals shall be provided. The seal shall be identified as capable of preventing the ingress ofcombustible dust or ignitible fibers/flyings and maintaining the type of protection but need not be explosionproof orflameproof.

Flexible cords used in Zone 20, Zone 21, and Zone 22 locations shall comply with all of thefollowing:(1) Be of a type listed for extra-hard usage(2) Contain, in addition to the conductors of the circuit, an equipment grounding conductor complying with 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 to minimize tension on the terminal

connections(5) Be terminated with a listed cord connector that maintains the protection technique of the terminal compartmentInformational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see UL 2225, .Revise to add an Informational Note regarding the requirements for cables, cable fittings and cord

connectors. There have been several instances of confusion regarding these Code requirements with respect totermination of cables with cable fittings.

Revise 506.15 to read as follows:506.15 Wiring Methods. Wiring methods shall maintain the integrity of the protection techniques and shall comply with

506.15(A), (B), or (C).(A) Zone 20. In Zone 20 locations, the following wiring methods shall be permitted.(1) Threaded rigid metal conduit or threaded steel intermediate metal conduit.(2) Type MI cable terminated with fittings listed for the location. Type MI cable shall be installed and supported in a

manner to avoid tensile stress at the termination fittings.Exception: MI cable and fittings listed for Class II, Division 1 locations shall be permitted to be used.(3) In industrial establishments with limited public access, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation, Type MC-HL cable, listed for use in Zone 20 locations, with acontinuous corrugated metallic sheath and overall jacket of suitable polymeric material, a separate equipment groundingconductor(s) in accordance with 250.122, and terminated with fittings listed for the application, shall be permitted. TypeMC-HL cable shall be installed in accordance with the provisions of Article 330, Part II.Exception: Type MC-HL cable and fittings listed for Class II, Division 1 locations shall be permitted to be used.(4) In industrial establishments with restricted public access, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation, and where the cable is not subject to physical damage, TypeITC-HL cable listed for use in Zone 1 or Class I, Division 1 locations, with a gas/vaportight continuous corrugatedmetallic sheath and an overall jacket of suitable polymeric material, and terminated with fittings listed for the application.Type ITC-HL cable shall be installed in accordance with the provisions of Article 727.(5) Fittings and boxes shall be identified for use in Zone 20 locations.Exception: Boxes and fittings listed for Class II, Division 1 locations shall be permitted to be used.(6) Where necessary to employ flexible connections, liquidtight flexible metal conduit with listed fittings, liquidtight

flexible nonmetallic conduit with listed fittings, or flexible cord listed for extra-hard usage and provided with listed fittingsshall be used. Where flexible cords are used, they shall also comply with 506.17 and shall be terminated with a listedcord connector that maintains the type of protection of the terminal compartment. Where flexible connections are subjectto oil or other corrosive conditions, the insulation of the conductors shall be of a type listed for the condition or shall beprotected by means of a suitable sheath.Exception: Flexible conduit and flexible conduit and cord fittings listed for Class II, Division 1 locations shall be

permitted to be used.Informational Note 1: See 506.25 for grounding requirements where flexible conduit is used.Informational Note 2: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see ANSI/UL 2225-2011, Cables and Cable-Fittings for Use in Hazardous (Classified) Locations.

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Report on Proposals – June 2013 NFPA 70(B) Zone 21. In Zone 21 locations, the wiring methods in (B)(1) and (B)(2) shall be permitted.(1) All wiring methods permitted in 506.15(A).(2) Fittings and boxes that are dusttight, provided with threaded bosses for connection to conduit, in which taps, joints,

or terminal connections are not made, and are not used in locations where metal dust is present, may be used.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see ANSI/UL 2225-2011, Cables and Cable-Fittings for Use in Hazardous (Classified) Locations.(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.(4) Type PLTC and Type PLTC-ER cable in accordance with the provisions of Article 725, including installation 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, MI, MV, or TC cable installed in ladder, ventilated trough, or ventilated channel cable trays in a single

layer, with a space not less than the larger cable diameter between two adjacent cables, shall be the wiring methodemployed. Single-conductor Type MV cables shall be shielded or metallic armored.(7) Nonincendive field wiring shall be permitted using any of the wiring methods permitted for unclassified locations.

Nonincendive field wiring systems shall be installed in accordance with the control drawing(s). Simple apparatus, notshown on the control drawing, shall be permitted in a nonincendive field wiring circuit, provided the simple apparatusdoes not interconnect the nonincendive field wiring circuit to any other circuit.Informational Note: Simple apparatus is defined in 504.2.Separation of nonincendive field wiring circuits shall be in accordance with one of the following:a. Be in separate cablesb. Be in multiconductor cables where the conductors of each circuit are within a grounded metal shieldc. Be in multiconductor cables where the conductors have insulation with a minimum thickness of 0.25 mm (0.01 in.)(8) Boxes and fittings shall be dusttight.506.16 Sealing. Where necessary to protect the ingress of combustible dust or ignitible fibers/flyings, or to maintain the

type of protection, seals shall be provided. The seal shall be identified as capable of preventing the ingress ofcombustible dust or ignitible fibers/flyings and maintaining the type of protection but need not be explosionproof orflameproof.506.17 Flexible Cords. Flexible cords used in Zone 20, Zone 21, and Zone 22 locations shall comply with all of 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 complying with 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 to minimize tension on the terminal

connections(5) Be terminated with a listed cord connector that maintains the protection technique of the terminal compartment.Informational Note: For further information on construction, testing and marking of cables, cable fittings, and cord

connectors, see ANSI/UL 2225-2011, Cables and Cable-Fittings for Use in Hazardous (Classified) Locations.The date of the publication has been added in accordance with 3.3.7.4 of the Rules Governing

Committee Projects. Location of the text was moved to the relevant sections.The panel action meets the intent of the proposal.

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

(2) Rigid metal conduit (RMC), intermediate metal conduit, electrical metallic tubing, dusttight wireways."Rigid Metal Conduit" is also referred to as “RMC” “Metallic Conduit”

Suggest that "RMC" be added to all references. This will make finding all references to "Rigid Metal Conduit" easierand more reliable.


_______________________________________________________________________________________________14-215 Log #2402 NEC-P14



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

(2) Rigid metal conduit, intermediate metal conduit (IMC), electrical metallic tubing, dusttight wireways."Intermediate Metal Conduit" is also referred to as “IMC” “Metallic Conduit”

Suggest that "IMC" be added to all references. This will make finding all references to “Intermediate Metal Conduit"easier and more reliable.


_______________________________________________________________________________________________14-215a Log #CP1406 NEC-P14


In 506.15(A)(6), designate the existing exception as "Exception No. 1" and add a new ExceptionNo. 2 to read:Exception #2: For elevator use, an identified elevator cable, type EO, ETP, or ETT, and as shown under the “use”

column in Table 400.4 for “Hazardous (classified) locations” and terminated with listed connectors that maintain the typeof protection of the terminal compartment shall be permitted.

Proposal 6-88 correctly identifies a situation where elevator cables are shown in Table 400.4 for“hazardous (classified) locations”, but the wiring method is not currently permitted in Chapter 5. The Panel agrees withthe submitter's substantiation in Proposal 6-88, however the Panel disagrees that it justifies removal of their use inhazardous (classified) locations. This proposal addresses the submitter’s substantiation and corrects this correlationproblem in Chapter 5.

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(6) Where necessary to employ flexible connections, liquidtight flexible metal conduit (LFMC) with listed fittings,liquidtight flexible nonmetallic conduit with listed fittings, or flexible cord listed for extra-hard usage and provided withlisted fittings shall be used. Where flexible cords are used, they shall also comply with 506.17 and shall be terminatedwith a listed cord connector that maintains the type of protection of the terminal compartment. Where flexibleconnections are subject to oil or other corrosive conditions, the insulation of the conductors shall be of a type listed forthe condition or shall be protected by means of a suitable sheath.

Informational Note: See 506.25 for grounding requirements where flexible conduit (LFMC) is used.

Liquidtight flexible metal conduit (LFMC) shall include an equipmentbonding jumper of the wire type in compliance with 250.102.




_______________________________________________________________________________________________14-217 Log #2857 NEC-P14



(6) Where necessary to employ flexible connections, liquidtight flexible metal conduit with listed fittings, liquidtightflexible nonmetallic conduit (LFNC) with listed fittings, or flexible cord listed for extra-hard usage and provided with listedfittings shall be used. Where flexible cords are used, they shall also comply with 506.17 and shall be terminated with alisted cord connector that maintains the type of protection of the terminal compartment. Where flexible connections aresubject to oil or other corrosive conditions, the insulation of the conductors shall be of a type listed for the condition orshall be protected by means of a suitable sheath.

Informational Note: See 506.25 for grounding requirements where flexible conduit (LFNC) is used."Liquidtight Flexible Nonmetallic Conduit" is also referred to as “LFNC”



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Revise text to read as follows:6)

Informational Note: See 506.25 for grounding requirements where flexible conduit (FMC) is used."Flexible Metal Conduit" is also referred to as “FMC”



_______________________________________________________________________________________________14-219 Log #2617 NEC-P14






_______________________________________________________________________________________________14-220 Log #1817 NEC-P14


Revise text to read as follows:(2) Rigid metal conduit, intermediate metal conduit, electrical metallic tubing (EMT), dusttight wireways.

"electrical metallic tubing" is also referred to as “EMT”Suggest that "EMT" be added to all references. This will make finding all references to "electrical metallic tubing" easier

and more reliable.[The following files are related: 100_EMT, 225_EMT, 230_EMT, 250_EMT, 300_EMT, 334_EMT, 374_EMT, 392_EMT,



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Revise text to read as follows:(6) Type MC, MI, MV, TC or TC-ER cable installed in ladder, ventilated trough, or ventilated channel cable trays in a

single layer, with a space not less than the larger cablediameter between two adjacent 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.

Add Type TC-ER cable terminated with listed fittings. Other Extended Run cable constructions arecurrently permitted. Type PLTC-ER, Type ITC-ER and Type TC-ER are all built to the same requirements. Add therequirement for termination with listed fittings as is required for these types of cables in 501.10(B), 50210(B), 503.10(A),and 505.15(C).

_______________________________________________________________________________________________14-222 Log #1444 NEC-P14


Revise text to read as follows:(7) Nonincendive field wiring Intrinsic safety type of protection “ic” shall be permitted using any of the wiring methods

permitted for unclassified locations. Nonincendive field wiring Intrinsic safety type of protection “ic” systems shall beinstalled in accordance with the control drawing(s). Simple apparatus, not shown on the control drawing, shall bepermitted in a nonincendive field wiring Intrinsic safety type of protection “ic” circuit, provided the simple apparatus doesnot interconnect the nonincendive field wiring Intrinsic safety type of protection “ic” circuit to any other circuit.Informational Note: is defined in 504.2.Separation of nonincendive field wiring Intrinsic safety type of protection “ic” circuits shall be in accordance with one of

the following:a. Be in separate cablesb. Be in multiconductor cables where the conductors of each circuit are within a grounded metal shieldc. Be in multiconductor cables where the conductors have insulation with a minimum thickness of 0.25 mm (0.01 in.).

The new edition of ISA 60079-11 (12.02.01) now includes the requirements for intrinsically safeequipment for combustible dust atmospheres. This includes a third category “ic” which would be suitable for Zone 22.This would then align with 505.15(C)(1)(g).

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be installed in cable trays or any raceway as stated in 506.15(C). Fiber Optic cables shall be sealed in accordance with506.16.



_______________________________________________________________________________________________14-224 Log #2486 NEC-P14


Revise text to read as follows:Flexible cords used in Zone 20,

Zone 21, and Zone 22 locations shall comply with all of 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 complying with 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 to minimize tension on the terminal


connectors, see UL 2225, .Revise to add an Informational Note regarding the requirements for cables, cable fittings and cord

connectors. There have been several instances of confusion regarding these Code requirements with respect totermination of cables with cable fittings.

Revise text to read as follows:Flexible cords used in Zone 20,

Zone 21, and Zone 22 locations shall comply with all of 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 complying with 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 to minimize tension on the terminal


connectors, see ANSI/UL 2225-2011, .The date of the publication has been added in accordance with 3.3.7.4 of the Rules Governing

Committee Projects. The panel recognizes that this proposal is contained in the submitter’s proposal 14-213. Seepanel action on Proposal 14-213.

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Add a new paragraph to read as follows:

Equipment marked with Group “IIIC” is suitable for applications requiring IIIA or IIIB equipment. Similarly, Similarly,equipment marked with Group “IIIB” is suitable for applications requiring IIIA equipment.renumber existing (D) to (E).renumber existing (E) to (F).

Although clear in the product standards, it is not clear in Article 506 that Group IIIC equipment issuitable for applications requiring Group IIIA or Group IIIB equipment. Similarly, it is not clear that Group IIIB equipmentis suitable for applications requiring Group IIIA equipment.

Add a new paragraph to read as follows:

Equipment marked with Group “IIIC” shall be permitted for applications requiring IIIA or IIIB equipment. Similarly,equipment marked with Group “IIIB” shall be permitted for applications requiring IIIA equipment.renumber existing (D) to (E).renumber existing (E) to (F).

The proposed text has been revised to replace the unenforceable phrase "is suitable".

_______________________________________________________________________________________________14-225a Log #CP1408 NEC-P14


Delete 506.21 entirely.The Code provision in 506.21 is covered in Chapter 2 [see 210.4(B)] and Chapters 1 through 4 apply

to Chapter 5 except where the latter supersedes them.

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Revise text to read as follows:Grounding and Bonding. Grounding and bonding shall comply with Article 250 and the requirements in

506.25(A) and (B).(A) Bonding. The locknut-bushing and double-locknut types of contacts shall not be depended on for bonding

purposes, but bonding jumpers with proper fittings or other approved means of bonding shall be used. Such means ofbonding shall apply to all intervening raceways, fittings, boxes, enclosures, and so forth, between Zone 20, Zone 21,and Zone 22 locations and the point of grounding for service equipment or point of grounding of a separately derivedsystem.Exception: The specific bonding means shall be required only to the nearest point where the grounded circuit

conductor and the grounding electrode conductor are connected together on the line side of the building or structuredisconnecting means as specified in 250.32(B) if the branch side overcurrent protection is located on the load side of thedisconnecting means.


jumper of the wire type in compliance with 250.102.Exception: In Zone 22 locations, the bonding jumper shall be permitted to be deleted where all of the following

conditions are met:(1) Listed liquidtight flexible metal conduit 1.8 m (6 ft) or less in length, with fittings listed for grounding, is used.(2) Overcurrent protection in the circuit is limited to 10 amperes or less.(3) The load is not a power utilization load.Grounding and Bonding. Grounding and bonding shall comply with Article 250.Informational Note: See 250.100 for additional bonding requirements in hazardous (classified) locations.

Duplication of text exists in five sections at 501.30, 502.30, 503.30, 505.25, and 506.25. This changewould move the requirements to Section 250.100 and eliminate duplication. The new text follows that already used insection 504.60.Companion proposals have been submitted for sections 250.100, 501.30, 502.30, 503.30 and 505.25.


_______________________________________________________________________________________________14-227 Log #2696 NEC-P14





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Revise text to read as follows:All fixed wiring above Class I locations shall be in metal raceways,

rigid nonmetallic conduit, electrical nonmetallic tubing (ENT), flexible metal conduit, liquidtight flexible metal conduit, orliquidtight flexible nonmetallic conduit, or shall be Type MC, AC, MI, manufactured wiring systems, or PLTC cable inaccordance with Article 725, or Type TC cable or Type ITC cable in accordance with Article 727. Cellular metal floorraceways or cellular concrete floor raceways shall be permitted to be used only for supplying ceiling outlets orextensions to the area below the floor, but such raceways shall have no connections leading into or through any Class Ilocation above the floor.

"Electrical Nonmetallic Tubing" is also referred to as “ENT”.Suggest that "ENT" be added to all references. This will make finding all references to "electrical nonmetallic tubing"



_______________________________________________________________________________________________14-229 Log #2041 NEC-P14



All fixed wiring above Class I locations shall be in metal raceways, rigidnonmetallic conduit (PVC), electrical nonmetallic tubing, flexible metal conduit, liquidtight flexible metal conduit, orliquidtight flexible nonmetallic conduit, or shall be Type MC, AC, MI, manufactured wiring systems, or PLTC cable inaccordance with Article 725, or Type TC cable or Type ITC cable in accordance with Article 727. Cellular metal floorraceways or cellular concrete floor raceways shall be permitted to be used only for supplying ceiling outlets orextensions to the area below the floor, but such raceways shallhave no connections leading into or through any Class I location above the floor.

"Rigid Polyvinyl Chloride Conduit" is also referred to as “PVC” and sometimes as “rigid nonmetallicconduit”Suggest that "PVC" be added to all references. This will make finding all references to easier and more reliable.


144Printed on 1/23/2012




All fixed wiring above Class I locations shall be in metal raceways (IMC),rigid nonmetallic conduit, electrical nonmetallic tubing, flexible metal conduit, liquidtight flexible metal conduit, orliquidtight flexible nonmetallic conduit, or shall be Type MC, AC, MI, manufactured wiring systems, or PLTC cable inaccordance with Article 725, or Type TC cable or Type ITC cable in accordance with Article 727. Cellular metal floorraceways or cellular concrete floor raceways shall be permitted to be used only for supplying ceiling outlets orextensions to the area below the floor, but such raceways shall have no connections leading into or through any Class Ilocation above the floor..




_______________________________________________________________________________________________14-231 Log #2799 NEC-P14



All fixed wiring above Class I locations shall be in metal raceways, rigidnonmetallic conduit, electrical nonmetallic tubing, flexible metal conduit (FMC), liquidtight flexible metal conduit, orliquidtight flexible nonmetallic conduit, or shall be Type MC, AC, MI, manufactured wiring systems, or PLTC cable inaccordance with Article 725, or Type TC cable or Type ITC cable in accordance with Article 727. Cellular metal floorraceways or cellular concrete floor raceways shall be permitted to be used only for supplying ceiling outlets orextensions to the area below the floor, but such raceways shall have no connections leading into or through any Class Ilocation above the floor.




145Printed on 1/23/2012



Revise text to read as follows:All fixed wiring above Class I locations shall be in metal

raceways, rigid nonmetallic conduit, electrical nonmetallic tubing, flexible metal conduit, liquidtight flexible metal conduit(LFMC), or liquidtight flexible nonmetallic conduit, or shall be Type MC, AC, MI, manufactured wiring systems, or PLTCcable in accordance with Article 725, or Type TC cable or Type ITC cable in accordance with Article 727. Cellular metalfloor raceways or cellular concrete floor raceways shall be permitted to be used only for supplying ceiling outlets orextensions to the area below the floor, but such raceways shall have no connections leading into or through any Class Ilocation above the floor.




_______________________________________________________________________________________________14-233 Log #2858 NEC-P14



All fixed wiring above Class I locations shall be in metal raceways, rigidnonmetallic conduit, electrical nonmetallic tubing, flexible metal conduit, liquidtight flexible metal conduit, or liquidtightflexible nonmetallic conduit (LFNC), or shall be Type MC, AC, MI, manufactured wiring systems, or PLTC cable inaccordance with Article 725, or Type TC cable or Type ITC cable in accordance with Article 727. Cellular metal floorraceways or cellular concrete floor raceways shall be permitted to be used only for supplying ceiling outlets orextensions to the area below the floor, but such raceways shall have no connections leading into or through any Class Ilocation above the floor.

"Liquidtight Flexible Nonmetallic Conduit" is also referred to as “LFNC”Suggest that “(LFNC)” be added to all references. This will make finding all references to "Liquidtight Flexible

Nonmetallic Conduit" easier and more reliable.


_______________________________________________________________________________________________14-234 Log #873 NEC-P14


Add a new last sentence after the warning text as follows:The warning sign(s) or label(s) shall comply with 110.21(B).

This proposal is one of several coordinated companion proposals to provide consistency of danger,caution, and warning sign or markings as required in the NEC. The proposed revision will correlate this warning markingrequirement with proposed 110.21(B) and the requirements in ANSI Z 535.4.


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_______________________________________________________________________________________________14-236 Log #875 NEC-P14





_______________________________________________________________________________________________14-237 Log #2061 NEC-P14

_______________________________________________________________________________________________Donald R. Offerdahl, Bismarck, ND

2Refer to Figure 514.3 (A) and 514.3 (B) for an illustration of classified location around dispensing devices

***InsertHere***

should be updated to NFPA 30A Figures 8.3.2(a) and 8.3.2(b) for illustrations ofclassified locations around dispensing devices. Above ground tanks were added because of the number of sites theseinstallation are commonly used.Note: Supporting material is available for review at NFPA Headquarters.

Accept the amended text for Footnote 2 of Table 514.3(B)(1) as proposed by the submitter.Revise the legends for the two diagrams to read as follows:Figure 514.3(a) Classified Areas Adjacent to Dispensers [30A: Figure 8.3.2(a)]

Figure 514.3(b) Classified Areas Adjacent to Dispenser Mounted on Aboveground Storage Tank [30A: Figure 8.3.2(b)]Repeat the legend from Figure 514.3(a) in Figure 514.3(b).

The legends for the figures need to be editorially revised to incorporate the correct figure numbersand the extract citations.

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Electrical wiring and equipment located at or serving motor fuel dispensing locations shall comply withArticle 514 in addition to the requirements of this article. All electrical wiring for power and lighting shall be installed onthe side of the wharf, pier, or dock opposite from the liquid piping system.Informational Note: For additional information, see NFPA 303-2011,

, and NFPA 30A-2008, .The following criteria shall be used for the purposes of applying

Table 514.3(B)(1) and Table 514.3(B)(2) to motor fuel dispensing equipment on floating or fixed piers, wharfs, or docks.Where the construction of floating docks, piers, or wharfs is closed so that there is no space

between the bottom of the dock, pier, or wharf and the water, such as concrete enclosed expanded foam or similarconstruction, and having integral service boxes with supply chases, the following shall apply:(1) The space above the surface of the floating dock, pier, or wharf shall be a Class I, Division 2 location with distances

as identified in Table 514.3(B)(1), Dispenser and Outdoor.(2) The space below the surface of the floating dock, pier, or wharf, having areas or enclosures such as tubs, voids,

pits, vaults, boxes, depressions, fuel piping chases, or similar spaces where flammable liquid or vapor can accumulate,shall be a Class I, Division 1 location.

Where the construction of piers, wharfs, or docks is open, such as decks built on stringerssupported by pilings, floats, pontoons, or similar construction, the following shall apply:(1) The area 450 mm (18 in) above the surface of the dock, pier, or wharf and extending 6.0 m (20 ft) horizontally in all

directions from the outside edge of the dispenser and down to the water level shall be Class 1, Division 2.(2) Enclosures such as tubs, voids, pits, vaults, boxes, depressions, piping chases, or similar spaces where flammable

liquids or vapors can accumulate within 6.0 m (20 ft) of the dispenser shall be a Class I, Division 1 location.Relocate the area classification requirements from 555.21(B) into a new 514.3(C ). Area classification

requirements for motor fuel dispensing are not appropriate to be located in Section 555.21.See the separate proposal to delete this material from 555.21(B).Though all of the proposed text from 555.21 is new to 514.3(C), the proposal is shown with underline and strike outs to

show the differences from the existing 555.21 text.

Panel 14 notes that motor fuel dispensing at marine facilities is under the scope of Article 514.This text is currently found in 555.21. Panel 14 recommends correlation with Article 555.

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Add text to read as follows:Underground wiring shall be installed in threaded rigid metal conduit or threaded steel

intermediate metal conduit (IMC). Any portion of electrical wiring that is below the surface of a Class I, Division 1, or aClass I, Division 2, location [as classified in Table 514.3(B)(1) and Table 514.3(B)(2)] shall be sealed within 3.05 m (10ft) of the point of emergence above grade. Except for listed explosionproof reducers at the conduit seal, there shall beno union, coupling, box, or fitting between the conduit seal and the point of emergence above grade. Refer to Table300.5.

.




_______________________________________________________________________________________________14-240 Log #2428 NEC-P14


Revise text to read as follows:Underground wiring shall be installed in threaded rigid metal conduit (RMC) or threaded

steel intermediate metal conduit. Any portion of electrical wiring that is below the surface of a Class I, Division 1, or aClass I, Division 2, location [as classified in Table 514.3(B)(1) and Table 514.3(B)(2)] shall be sealed within 3.05 m (10ft) of the point of emergence above grade. Except for listed explosionproof reducers at the conduit seal, there shall beno union, coupling, box, or fitting between the conduit seal and the point of emergence above grade. Refer to Table300.5.


and more reliable.


149Printed on 1/23/2012


_______________________________________________________________________________________________Stanley J. Folz, Morse Electric Company

Revise text to read as follows:Each dispensing device shall be

provided with a means to remove all external voltage sources, including power, communications, data, and video circuitsand including feedback, during periods of maintenance and service of the dispensing equipment. The location of thismeans shall be permitted to be other than inside or adjacent to the dispensing device. The means shall be capable ofbeing locked in the open position. The provision for locking or adding a lock to the disconnecting means shall beinstalled on or at the switch, circuit breaker or other device used as the disconnecting means and shall remain in placewith or without the lock installed.

This proposal has been developed by the Usability Task Group assigned by the Technical CorrelatingCommittee. The committee members were Stanley Folz, James Dollard, William Fiske, David Hittinger, Andy Juhasz,Amos Lowrance, Susan Newman-Scearce, Marc Bernsen and Vincent Zinnante. Requirements for a disconnectingmeans to be lockable in the open position exist in numerous locations in the NEC. A new section has been proposed inArticle 110 to consolidate the requirements for a disconnecting means required to be “capable of being locked in theopen position” in a single section for clarity. It is understood that this requirement includes more than disconnecting andlocking electrical power sources.This proposal is intended to facilitate a lockout/tagout scenario. It is equally important to ensure that the means for

placing the lock remain in place. The concept suggested by this proposal is necessary to provide correlation throughoutthe NEC with respect to the capability of placing a lock on a disconnecting means to secure it in the open position.

Revise text to read as follows:Each dispensing device shall be

provided with a means to remove all external voltage sources, including power, communications, data, and video circuitsand including feedback, during periods of maintenance and service of the dispensing equipment. The location of thismeans shall be permitted to be other than inside or adjacent to the dispensing device. The means shall be capable ofbeing locked in the open position, in accordance with 110.25.

The proposed additional language is contained in Proposal No. 1-130, and if accepted will becontained in 110.25. It is thus redundant in Article 514.

_______________________________________________________________________________________________14-241a Log #CP1400 NEC-P14


Delete 515.2 entirely.The one definition in 515.2 is redundant with the scope statement in 515.1.

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Underground wiring shall be installed in threaded rigid metal conduit (RMC) or threaded steelintermediate metal conduit or, where buried under not less than 600 mm (2 ft) of cover, shall be permitted in Type PVCconduit, Type RTRC conduit, or a listed cable. Where Type PVC conduit or Type RTRC conduit is used, threaded rigidmetal conduit (RMC) or threaded steel intermediate metal conduit shall be used for not less than the last 600 mm (2 ft)of the conduit run to the conduit point of emergence from the underground location or to the point of connection to anaboveground raceway. Where cable is used, it shall be enclosed in threaded rigid metal conduit (RMC) or threadedsteel intermediate metal conduit from the point of lowest buried cable level to the point of connection to the abovegroundraceway.


and more reliable.


_______________________________________________________________________________________________14-243 Log #2488 NEC-P14


Revise the Informational Note for 516, 516.1, 516.3(A)(2), 516.10(A)(6) and 516.10(C)(4)(b) toreflect the 2007 edition of NFPA 33 and NFPA 34.

Revise the referenced Informational Notes in Article 516 to reflect the 2007 editions of NFPA 33 andNFPA 34 from which the extracted text in Article 516 is derived. The 2011 edition of NFPA 33 contains requirementsthat are incongruous with the requirements in Article 516. The 2011 edition of NFPA 34 Scope is expanded to includeprocesses not covered by Article 516, and furthermore contains requirements that are incongruous with therequirements in Article 516.

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_______________________________________________________________________________________________Geoffrey A. Raifsnider, Global Finishing Solutions

Revise text to read as follows:For the purpose of this article, the following definitions shall apply.

Any fully enclosed, partly enclosed, or unenclosed area in which dangerous quantities offlammable or combustible 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 a spray booth orspray room or limited finishing workstation, as herein defined; (3) the interior of any exhaust plenum, eliminator section,or scrubber section; (4) the interior of any exhaust duct or exhaust stack leading from a spray application process; (5)the interior of any air recirculation filter house or enclosure, including secondary recirculation particulate filters; (6) anysolvent concentrator (pollution abatement) unit or solvent recovery (distillation) unit. The following shall not beconsidered part of the spray area: (1) Fresh air make-up units; (2) Air supply ducts and air supply plenums; (3)Recirculation air supply ducts downstream of secondary filters; (4) Exhaust ducts from solvent concentrator (pollutionabatement) units

May beNormally, locations outside of building or localized operations within a larger room orspace. Such are normally provided with some local vapor extraction/ventilation system. In automated operations, thearea limits shall be the maximum area in the direct path of spray operations. In manual operations, the area limits shallbe the maximum area of spray when aimed at 180 degrees to the application surface.

A power-ventilated enclosure for a spray application operation or process that confines andlimits the escape of the material being sprayed, including vapors, mists, dusts, and residues that are produced by thespraying operation and conducts or directs these materials to an exhaust system.

An is an enclosure or insert within a larger room used for spray/coating/dipping applications.A spray booth may be fully enclosed or have open front or face and may include separate conveyor entrance and exit.The spray booth is provided with a dedicated ventilation exhaust but may draw supply air from the larger room or have adedicated air supply.

A power-ventilated fully enclosed room used exclusively for open spraying of flammable orcombustible materials.

A is a purposefully enclosed room for spray/coating/dipping applications provided withdedicated ventilation supply and exhaust. Normally the room is configured to house the item to be painted, providingreasonable access around the item/process. Depending on the size of the item being painted, such rooms may actuallybe the entire building or the major portion thereof.

Per the informational note in Article 516, it was the intent of this section to contain text extracted fromNFPA 33 2011 Edition. It appears revisions to NFPA 70 were complete before the changes to NFPA 33 were publishedand there are discrepancies between the two editions. The proposed changes incorporate definitions from the 2011Edition of NFPA 33.

The proposed changes have potentially significant impact on electrical installations in finishingprocess operations without substantiation. Panel 14 suggests that a task group be formed consisting of Panel 14members and members of the Technical Committee on Finishing Processes to harmonize the requirements amongArticle 516 and NFPA 33, , and NFPA 34,

.

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Revise text to read as follows: Normally, locations outside of buildings or localized operations within a larger room or space. Such are

normally provided with some local vapor extraction/ventilation system. In automated operations, the area limits shall bethe maximum area in the direct path of spray operations. In manual operations, the area limits shall be the maximumarea of spray when aimed at 180 degrees to the application surface.

Such are normally provided with some local vapor extraction/ventilation system. In automatedoperations, the area limits shall be the maximum area in the direct path of spray operations. In manual operations, thearea limits shall be the maximum area of spray when aimed at 180 degrees to the application surface.


A spray booth may be fully enclosed or have open front or face and may include separateconveyor entrance and exit. The spray booth is provided with a dedicated ventilation exhaust but may draw supply airfrom the larger room or have a dedicated air supply.

A purposefully enclosed room built for spray/coating/dipping applications provided with dedicatedventilation supply and exhaust. Normally the room is configured to house the item to be painted, providing reasonableaccess around the item/process. Depending on the size of the item being painted, such rooms may actually be theentire building or the major portion thereof.

: Normally the room is configured to house the item to be painted, providing reasonable accessaround the item/process. Depending on the size of the item being painted, such rooms may actually be the entirebuilding or the major portion thereof.



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Revise text to read as follows:Classification is based on dangerous quantities of flammable vapors, combustible

mists, residues, dusts, or deposits.(A) 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:(1) The interior of any open or closed container of a flammable liquid(2) The interior of any dip tank or coating tank Informational Note: For additional guidance and explanatory diagrams,

see 4.3.5 of NFPA 33-2011, , and Sections4.2, 4.3, and 4.4 of NFPA 34-2011,

The following spaces shall be considered Class I, Division 1, or Class I,Zone 1, or Class II, Division 1 locations, as applicable:(1) The interior of spray booths and rooms except as specifically provided in 516.3(D).(2) The interior of exhaust ducts.(3) Any area in the direct path of spray operations.(4) For open dipping and coating operations, all space within a 1.5-m (5-ft) radial distance from the vapor sources

extending from these surfaces to the floor. The vapor source shall be the liquid exposed in the process and thedrainboard, and any dipped or coated object from which it is possible to measure vapor concentrations exceeding 25percent of the lower flammable limit at a distance of 300 mm (1 ft), in any direction, from the object.(5) Sumps, pits, or belowgrade channels within 7.5 m (25 ft) horizontally of a vapor source. If the sump, pit, or channel

extends beyond 7.5 m (25 ft) from the vapor source, it shall be provided with a vapor stop or it shall be classified asClass I, Division 1 for its entire length.(6) All space in all directions outside of but within 900 mm (3 ft) of open containers,supply containers, spray gun

cleaners, and solvent distillation units containing flammable liquids.. The following spaces shall be considered Class I, Division 2, or Class I,

Zone 2, or Class II, Division 2 as applicable.For open spraying, all space outside of but within 6 m (20 ft) horizontally and 3 m (10 ft) vertically

of the Class I, Division 1 or Class I, Zone 1 location as defined in 516.3(A), and not separated from it by partitions. SeeFigure 516.3(C)(1). [33:6.5.1]

If spray application operations are conducted within aclosed-top, open-face, or open-front booth or room, as shown in Figure 6.5.2, any electrical wiring or utilizationequipment located outside the booth or room but within 915 mm (3 ft) of any opening shall be suitable for Class I,Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 locations, whichever is applicable any electrical wiring orutilization equipment located outside of the booth or room but within the boundaries designated as Division 2 of Zone 2in Figure 516.3(C)(2) shall be suitable for Class I, Division 2, Class I, Zone 2, or Class II, Division 2 locations, whicheveris applicable. The Class I, Division 2, Class I, Zone 2, or Class II, Division 2 locations shown in Figure 516.3(C)(2) shallextend from the edges of the open face or open front of the booth or room in accordance with the following:(a) If the exhaust ventilation system is interlocked with the spray application equipment, the Division 2 or Zone 2

location shall extend 1.5 m (5 ft) horizontally and 900 mm (3 ft) vertically from the open face or open front of the booth orroom, as shown in Figure 516.3(C)(2), top.(b) If the exhaust ventilation system is not interlocked with the spray application equipment, the Division 2 or Zone 2

location shall extend 3 m (10 ft) horizontally and 900 mm (3 ft) vertically from the open face or open front of the booth orroom, as shown in Figure 516.3(C)(2), bottom.For the purposes of this subsection, interlocked shall mean that the spray application equipment cannot be operated

unless the exhaust ventilation system is operating and functioning properly and spray application is automaticallystopped if the exhaust ventilation system fails. [33:6.5.2.26.5.2]

[INSERT FIGURE 6.5.2 FROM NFPA 33 HERE]

For spraying operations conducted within an open top spray booth, the space 900 mm (3 ft)vertically above the booth and within 900 mm (3 ft) of other booth openings shall be considered Class I, Division 2;

154Printed on 1/23/2012

Report on Proposals – June 2013 NFPA 70Class I, Zone 2; or Class II, Division 2. [33:6.5.3](4) Enclosed Booths and Rooms. For spraying operations confined to an enclosed spray booth or room, electrical area

classification shall be as follows:(a) 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 Figure 6.5.4.(b) Where exhaust air is recirculated and all requirements of Section 7.5 are met, both of the following shall apply:(1) The interior of any recirculation path from the secondary particulate filters up to and including 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 isapplicable.(2) The interior of fresh air supply ducts shall be unclassified.(c) Where exhaust air is not recirculated, the interior of fresh air supply ducts and fresh air supply plenums shall be

unclassified the space within 900 mm (3 ft) in all directions from any openings shall be considered Class I, Division 2; ofClass I, Zone 2; or Class I, Division 2 as shown in Figure 516.3(C)(4). [33:6.5.4]

[INSERT FIGURE 6.5.4 FROM NFPA 33 HERE]

Per the informational note in Article 516, it was the intent of this section to contain text extracted fromNFPA 33 2011 Edition. It appears revisions to NFPA 70 were complete before the changes to NFPA 33 were publishedand there are discrepancies between the two additions. The proposed changes incorporate definitions from the 2011Edition of NFPA 33.


_______________________________________________________________________________________________14-247 Log #1966 NEC-P14


At the end of paragraph (a), delete the reference to Figure 516.3(C)(2), and top, and insert thereference Figure 516.3(C)(2)(a) so that the paragraph will read as follows:(a) If the exhaust ventilation system is interlocked with the spray application equipment, the Division 2 or Zone 2

location shall extend 1.5 m (5 ft) horizontally and 900 mm (3 ft) vertically from the open face or open front of the booth orroom, as shown in Figure 516.3(C)(2), top Figure 516.3(C)(2)(a).

If the proposal to separate the top and bottom diagrams of Fiugre 516.3(C)(2) is approved, then thischange is necessary to make the proper reference to the Figures in the text. Without a reference to the status of theexhaust ventilation in the Figure, there is some confusion that can lead to an error in the field.


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At the end of paragraph (b), delete the reference to Figure 516.3(C)(2), and bottom, and insert thereference Figure 516.3(C)(2)(b) so that the paragraph will read as follows:(b) If the exhaust ventilation system is not interlocked with the spray application equipment, the Division 2 or Zone 2

location shall extend 3 m (10 ft) horizontally and 900 mm (3 ft) vertically from the open face or open front of the booth orroom, as shown in Figure 516.3(C)(2), bottom Figure 516.3(C)(2)(b).

If the proposal to separate the top and bottom diagrams of Fiugre 516.3(C)(2) is approved, then thischange is necessary to make the proper reference to the Figures in the text. Without a reference to the status of theexhaust ventilation in the Figure, there is some confusion that can lead to an error in the field.


_______________________________________________________________________________________________14-249 Log #1968 NEC-P14


Separate the top diagram and the bottom diagram and place each into a separate figure with wordsadded to the caption to indicate the status of the exhaust ventilation with respect to the spray application equipment.The top diagram will then become Figure 516.3(C)(2)(a) with a caption that reads as follows:

It is confusing to follow the text in 516.3(C)(2) and compare it to the Figure since there is no indicationin the figure which diagram has exhaust ventilation interlocked with the spray application equipment and which does not.This confusion can lead to an expensive mistake in the field. Since the figures were separate in the original NFPA 33,they should also be kept separate in NFPA 70. The words added to the caption should eliminate any confusion as towhich diagram applies to a particular installation.


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Separate the top diagram and the bottom diagram and place each into a separate figure with wordsadded to the caption to indicate the status of the exhaust ventilation with respect to the spray application equipment.The bottom diagram will then become Figure 516.3(C)(2)(b) with a caption that reads as follows:

It is confusing to follow the text in 516.3(C)(2) and compare it to the Figure since there is no indicationin the figure which diagram has exhaust ventilation interlocked with the spray application equipment and which does not.This confusion can lead to an expensive mistake in the field. Since the figures were separate in the original NFPA 33,they should also be kept separate in NFPA 70. The words added to the caption should eliminate any confusion as towhich diagram applies to a particular installation.


_______________________________________________________________________________________________14-251 Log #2405 NEC-P14



Unless specifically listed for locations containing deposits ofdangerous quantities of flammable or combustible vapors, mists, residues, dusts, or deposits (as applicable), there shallbe no electrical equipment in any spray area as herein defined whereon deposits of combustible residue may readilyaccumulate, except wiring in rigid metal conduit, intermediate metal conduit (IMC), Type MI cable, or in metal boxes orfittings containing no taps, splices, or terminal connections. [ 6.4.2]




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Unless specifically listed for locations containing deposits ofdangerous quantities of flammable or combustible vapors, mists, residues, dusts, or deposits (as applicable), there shallbe no electrical equipment in any spray area as herein defined whereon deposits of combustible residue may readilyaccumulate, except wiring in rigid metal conduit (RMC), intermediate metal conduit, Type MI cable, or in metal boxes orfittings containing no taps, splices, or terminal connections. [ 6.4.2]


and more reliable.


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(A) Wiring and Equipment—Vapors. All electrical wiring and equipment within the Class I location (containing vaporonly — not residues) defined in 516.3 shall comply with the applicable provisions of Article 501 or Article 505, asapplicable.

Unless specifically listed for locations containing deposits of dangerous quantities of flammable or combustible vapors,mists, residues, dusts, or deposits (as applicable), there shall be no electrical equipment in any spray area as hereindefined whereon deposits of combustible residue may readily accumulate, except wiring in rigid metal conduit,intermediate metal conduit, Type MI cable, or in metal boxes or fittings containing no taps, splices, or terminalconnections. [ 6.4.2]

(1) Light fixtures, like that shown in Figure 6.6.1, that are attached to the walls or ceiling of a spray area but that areoutside any classified area and are separated from the spray area by glass panels that meet the requirements ofSection 5.5 shall be suitable for use in unclassified locations. Such fixtures shall be serviced from outside the sprayarea. [ 6.6.1](2) Light fixtures, like that shown in Figure 6.6.1, that are attached to the walls or ceiling of a spray area, that are

separated from the spray area by glass panels that meet the requirements of Section 5.5; 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 suitable for such location.Such fixtures shall be serviced from outside the spray area. [ 6.6.2]

[INSERT FIGURE 6.6.1 FROM NFPA 33]

(3) Light fixtures, like that shown in Figure 6.6.3, that are an integral part of the walls or ceiling of a spray area shall bepermitted to be separated from the spray area by glass panels that are an integral part of the fixture. Such fixtures shallbe listed for use in Class I, Division 2; Class I, Zone 2; Class II, Division 2, or Zone 22 locations, whichever is applicable,and also shall be listed for accumulations of deposits of combustible residues. Such fixtures shall be permitted to beserviced from inside the spray area. [ 6.6.3]

[INSERT FIGURE 6.6.3 FROM NFPA 33]

Illumination, Illumination of readily ignitable areas through panels of glass or other transparent or translucent materialshall be permitted only if it complies with the following:(1) Fixed lighting units are used as the source of illumination.(2) The panel effectively isolates the Class I location from the area in which the lighting unit is located.(3) The lighting unit is identified for its specific location.(4) The panel is of a material or is protected so that breakage is unlikely.(5) The arrangement is such that normal accumulations of hazardous residue on the surface of the panel will not be

raised to a dangerous temperature by radiation or conduction from the source of illumination.Per the informational note in Article 516, it was the intent of this section to contain text extracted from

NFPA 33 2011 Edition. This proposal seeks to bring the two documents closer together by including the wording andfigures from NFPA 33 covering the types and locations of light fixtures. Light fixtures defined as acceptable for use inand around spray booths in NFPA 33 where not seen as acceptable by those using NFPA 70. The proposed changesshould eliminate conflicting interpretations regarding suitable light fixtures.


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Add a new last sentence as follows:"…The equipment shall carry a prominent, permanently installed warning regarding the necessity for this grounding

feature. The warning sign(s) or label(s) shall comply with 110.21(B).This proposal is one of several coordinated companion proposals to provide consistency of danger,

caution, and warning sign or markings as required in the NEC. The proposed revision will correlate this warning markingrequirement with proposed 110.21(B) and the requirements in ANSI Z 535.4.


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report on proposals – june 2013 nfpa 70 … · ansi/isa–tr12.21.01, ... report on proposals –...

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