EFCOG Best Practice #178

EFCOG Best Practice #178

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Best Practice Title: Adoption of NFPA 70 2014 in place of NFPA 70 2011

Facility: DOE Complex

Point of Contact: Andrew Drutel, PE, Savannah River Site, 803-952-9380,

[email protected] (Primary contact)

Michael Hicks NE-Idaho, 208-526-3724, [email protected]

John McAlhaney, PE, Savannah River Site, 803-557-9002, [email protected]

Brief Description of Best Practice: NFPA 70 2014 is recommended for approval across the

DOE Complex as an upgrade to NFPA 70 2011 in 10 CFR 851 Worker Safety and Health Plans

(WSHP).

Why the best practice was used: 10 CFR 851 lists safety and health consensus standards with

which the contractor must comply when applicable with site hazards (851.23). Only the versions

of consensus standards that were in effect on February 9, 2006 were promulgated pursuant to

rulemaking therefore only those specifically cited versions are required by the Rule. Contractors

may include successor versions of the consensus standards that provide equal or greater worker

protection if included in their DOE-approved worker safety and health program.

What are the benefits of the best practice: The use of NFPA 70 2014 is at least as protective

as the 2011 edition, and even more protective in some areas, such that the new edition should be

considered for DOE Complex wide acceptance. NFPA 70 2014 is recommended for approval

across the DOE Complex as an upgrade to NFPA 70 2011.

What problems/issues were associated with the best practice: There were no issues associated

with this gap analysis. Adoption of the 2014 Edition of NFPA 70 provides a level of protection

“As Safe or Safer” than the 2011 version.

How the success of the Best Practice was measured: N/A

Description of process experience using the Best Practice: At the time this analysis was

performed, process experience did not exist. .

mailto:[email protected]



Attachment to EFCOG Best Practice #178 Technical Evaluation of the Changes in NFPA 70 between 2011 and 2014 Editions

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Date 08/18/2014

Code/Standard Title: NFPA 70® – National Electrical Code

®

10CFR851 UPGRADE EVALUATION

TITLE: Technical Evaluation of the Changes in NFPA 70 between 2011 and 2014 Editions

Note:

National Fire Protection Association ®, NFPA ®, NFPA 70®, National Electrical Code ®, NEC ®, National Electrical

Safety Code®, NESC® are registered trademarks of the National Fire Protection Association, Quincy, MA.


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1. DESCRIPTION

10 CFR 851 - “DOE Worker Health and Safety Program” requires that the 2005 edition of NFPA

70 - “National Electrical Code” (NEC) be utilized. The purpose of this evaluation is to

document the acceptability of the changes introduced in 2014 edition of NFPA 70 as compared

to the 2011 edition and to identify and evaluate the impact of the changes to the safety and health

of workers. 2008 and 2011 editions of NFPA 70 were reviewed separately.

The sections of the NEC that deal strictly with residential systems or systems not in use at in

industrial applications are not included in this evaluation. Furthermore, a majority of editorial

changes, clarifications, additions of definitions, rearrangement of sections and related cross-

reference revisions, or changes related to bringing the code in alignment with the NEC Style

Manual are not considered to have an impact on safety and, therefore, are in most cases not

included in this evaluation. No Informational Notes and no Informative Annexes were evaluated

as they are not part of the Code text and have no enforceable meaning.

2. TECHNICAL JUSTIFICATION

The attached comparison was prepared by Andrew Drutel and reviewed by Jackie McAlhaney.

The review identified no detrimental impacts to worker safety and health and concluded that the

use of the 2014 edition of NFPA 70 is as protective to the worker as the 2008 and 2011 editions.

Attachment #4 provides comparisons of changes that were made to 2011 Edition of NEC in 2014

Edition of the code. Each line item listed in the “Comparison Table” has been reviewed and rated

for the impact on worker safety. A rating of “1” (editorial), “2” (technical improvement), or “3”

(potential safety consequence) has been assigned for each item. Any item with a ranking of “3”

requires additional justification. Examples of the three ratings are provided below.

1. Editorial Change – No impact to worker health or safety

Example: Adding a metrication reference.

2. Technical Improvement – Addition, enhancement, or change in methodology or

acceptance criteria that does not degrade worker safety when compared to the previous

edition.

Example: Adding requirements for equipment grounding for lighting switches supplied

by a general purpose branch circuit.

3. Potential Safety Consequence – Changes or revisions that potentially make the electrical

installation less robust and could affect personnel safety. A ranking of “3” requires

additional justification or further action.

Example: Change in an overcurrent protection of a conductor or equipment which could

result in reduced margin of safety.

In some cases text of a particular revised section was truncated, capturing only portion of the text

relevant to a particular change.

The changes are depicted as follows:

Text shown in strikethrough font represents portions of the code which were deleted,


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Underlined font represents new text being added to the code.

3. CONCLUSION

As demonstrated in Attachment #4, there have been no changes made to the NFPA 70, National

Electrical Code in the 2014 Edition that could present adverse impact to worker health or safety

(rated “3”, as described above). Furthermore, the provisions of the 2014 edition are at least as

protective as the edition specified in 10 CFR 851 (NFPA 70-2005) , NFPA 70-2008, and NFPA

70-2011.

4. COST IMPACT

The provisions of the NFPA 70, National Electrical Code are not retroactive; therefore, no cost

impact related to implementation of the new editions of the code is anticipated. Some of the

changes may affect future installations; however, the costs of design, construction, and startup

testing will be factored in during the project development stage.

Cost of implementing the requirement for sealing certain types of engineering documents by a

Professional Engineer, addressed in 5. Notes, Items 1 and 2, below, is considered to be

negligible.

5. NOTES

1. Additional code sections now require that the design documentation be prepared by a

qualified licensed professional engineer engaged primarily in the subject design (e.g.

Article 490, Equipment Over 1000 V, Nominal, Section 490.48).

2. In Sections 620.62, 700.28, 701.27, and 708.54 a new requirement was added for

selective coordination studies of overcurrent-protection devices to be prepared by a

licensed professional engineer or other qualified persons.

3. Article 590, Temporary Installations, Section 590.4(J) no longer allows cable assemblies

and flexible cords and cables used as branch circuits or feeders to be installed on the floor

or on the ground (this restriction does not apply to extension cables). Procedures

applicable to temporary installations will need to be reviewed to ensure compliance with

this requirement.

4. This document, along with NFPA 70-2011 evaluation, shall be considered when adopting

2014 edition of the National Electrical Code.

6. REFERENCES

1. 10 CFR 851, Worker Safety and Health Program


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2. ANSI/ISA 12.27.01 – 2011, Requirements for Process Sealing Between Electrical

Systems and Flammable or Combustible Process Fluids

3. ANSI/ISA 60079-31– 2013, Explosive Atmospheres – Part 31: Equipment Dust Ignition

Protection by Enclosure “t”

4. ANSI/ISA 61241-1 – 2006, Electrical Apparatus for Use in Zone 21 and Zone 22

Hazardous (Classified) Locations − Protection by Enclosures “tD”

5. ANSI/UL 508 – 1999, UL Standard for Safety Industrial Control Equipment

6. ANSI/UL 2225 – 2013, UL Standard for Safety Cables and Cable-Fittings For Use In

Hazardous (Classified) Locations

7. ASTM E 11 – 2009, Standard Specification for Wire Cloth and Sieves for Testing

Purposes

8. IEEE 80 – 2000, Guide for Safety In AC Substation Grounding.

9. NFPA 20 – 2013, Standard for Installation of Stationary Pumps for Fire Protection

10. NFPA 33 – 2011, Standard for Spray Application Using Flammable or Combustible

Materials

11. NFPA 34 – 2011, Standard for Dipping, Coating, and Printing Processes Using

Flammable or Combustible Liquids

12. NFPA 70, National Electrical Code (2005, 2008, 2011, and 2014 editions)

13. NFPA 70E – 2004, Standard for Electrical Safety in the Workplace

14. NFPA 72 – 2013, National Fire Alarm and Signaling Code

15. NFPA 79 – 2015, Electrical Standard for Industrial Machinery

16. NFPA 90A – 2015, Standard for the Installation of Air-Conditioning and Ventilating

Systems

17. NFPA 499 – 2013 Recommended Practice for the Classification of Combustible Dusts

and of Hazardous (Classified) Locations for Electrical Installations in Chemical Process

Areas

7. ATTACHMENTS

1. Email, Drutel to NFPA Licensing, dated March 13, 2014

2. Letter, Berry (NFPA) to Drutel, dated March 21, 2014

3. Evaluation Sample

4. Comparison Table


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Attachment #1


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Attachment #2


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Attachment #3

Technical Evaluation of the Changes in NFPA 70 between 2011 and 2014 Editions

Attachment #4 - Comparison Table

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Note: Reprinted with permission from NFPA 70®-2014 Redline, National Electrical Code

®, Copyright © 2013, National Fire Protection

Association, Quincy, MA. The reprinted material is not the complete and official position of the NFPA on the referenced subject, which is represented only by the standard in its entirety.

CODE-WIDE CHANGES Note: Changes listed under this heading are common to one or more articles and multiple sections of the NEC, and are addressed here in lieu of

specific articles/sections they appear in. 2014 NEC (with changes) Change Description and

Impact Rank

110.21 Marking.

(B) Field-Applied Hazard Markings. Where caution,

warning, or danger signs or labels are required by this

Code, the labels shall meet the following requirements:

(1) The marking shall adequately warn of the hazard using

effective words and/or colors and/or symbols.

(2) The label shall be permanently affixed to the equipment or

wiring method and shall not be hand written.

Exception to (2): Portions of labels or markings that are

variable, or that could be subject to changes, shall be per-

mitted to be hand written and shall be legible.

(3) The label shall be of sufficient durability to withstand the

environment involved.

Change Description: Removed hazard marking requirements repeated throughout the code and replaced with a reference to Section 110.21(B), covering hazard marking requirements generically. Editorial change, simplifying use of the NEC.

Impact(s) : No negative impact.

1

110.25 Lockable Disconnecting Means. Where a discon-

necting means is required to be lockable open elsewhere in

this Code, it shall be capable of being locked in the open

position. The provisions for locking shall remain in place

with or without the lock installed.

Exception: Cord-and-plug connection locking provisions

shall not be required to remain in place without the lock

installed.

Change Description: Removed lockable disconnecting means requirements repeated throughout the code and replaced with a reference to Section 110.25, covering these requirements generically. Editorial change, simplifying use of the NEC. Impact(s) : No negative impact.

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200.6 Means of Identifying Grounded

Conductors.

(A) Sizes 6 AWG or Smaller. An insulated grounded con-

Change Description: This change offers more choices to the installer and allows identification of grounded conductor by system if multiple systems

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ductor of 6 AWG or smaller shall be identified by one of

the following means:

(3) Three continuous white or gray stripes along the con-

ductor’s entire length on other than green insulation.

are installed. Impact(s) : No negative impact.

Raised the 600V threshold in the NEC to 1000 V, based on the proposals submitted by the High Voltage Task Group appointed by the

NEC Correlating Committee. Previously used reference to the National Electrical Safety Code (NESC) for voltages above 600V created confusion for personnel responsible for design of such systems.

Change Description: The change is related to introduction of emerging technologies (e.g., wind power generating systems, photovoltaic systems) operating over 600V. To ensure safety the equipment must first be tested and found acceptable for use at the higher voltage. In addition, NEC must include prescriptive requirements to permit installations at these higher operating voltages. This change was made in majority cases where the previous code limited the installation voltage to 600V. Also, as a consequence of this change, the articles and sections referring to installations “over 600V” in the previous edition of the code were revised accordingly to “over 1000V”. Impact(s) : This change is deemed to be acceptable and safe as long as the above criteria are applied (i.e. equipment tested/approved and NEC requirements exist for installation at up to 1000V).

2

Revised text of several sections to expand applicability from “Buildings” to “Buildings and Other Structures”.

Change Description: This change clarifies the intent of the NEC addressing applicability of the code to structures which cannot be classified as “buildings”. Impact(s) : No negative impact.

2

The title of the definition of the term “metal-enclosed switchgear” has been changed to

Change Description: As revised, the definition now applies to all switchgear types,

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simply “switchgear,” resulting in more expanded application of this term. The revised definition also allows for inclusion of the term “switchgear” in existing rules that only include the term “switchboards,” but that requirement covers both types of equipment. The last sentence of the existing definition is more informative than descriptive and, accordingly, has been crafted into an informational note to this definition. All switchgear covered by the NEC rules are intended to be metal-enclosed types. As revised, the definition now applies to all switchgear types, such as metal-clad switchgear, metal-enclosed switchgear and low-voltage power circuit breaker switchgear as indicated in the new informational note. Action by Code-Making Panel 9 on Proposal 9-104a results in a change in the title of Article 408 from “Switchboards and Panelboards” to “Switchboards, Switchgear, and Panelboards,” and the scope was revised to include switchgear. Article 490 was also revised to incorporate the term “switchgear” in place of the term “metal-enclosed switchgear.” Other NEC revisions have been made to replace the term “metal-enclosed switchgear” with “switchgear.”

such as metal-clad switchgear, metal-enclosed switchgear and low-voltage power circuit breaker switchgear as indicated in the new informational note. Action by Code-Making Panel 9 on Proposal 9-104a results in a change in the title of Article 408 from “Switchboards and Panelboards” to “Switchboards, Switchgear, and Panelboards,” and the scope was revised to include switchgear. Article 490 was also revised to incorporate the term “switchgear” in place of the term “metal-enclosed switchgear.” Other NEC revisions have been made to replace the term “metal-enclosed switchgear” with “switchgear.” Impact(s) No negative impact.

Multiple definitions moved to Article 100 Change Description: This change is consistent with the NEC Style Manual which requires that definitions appearing in two or more articles be located in Article 100.

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2011 NEC added definitions for Overhead Service Conductors and Underground Service Conductors in Article 100, but these additional terms were not added to Article 250 and other applicable articles of the code discussing services.

Change Description: The terms Overhead Service Conductors and/or Underground Service Conductors were added in Article 250 for clarity and to reflect changes to service definitions and terminology made in the 2011 NEC. Impact(s) : No negative impact.

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ARTICLE 100 Definitions

I. General Accessible, Readily (Readily Accessible). Capable of being

reached quickly for operation, renewal, or inspections without

requiring those to whom ready access is requisite to actions

such as to use tools, to climb over or remove obstacles, or to

resort to portable ladders, and so forth.

Change Description: This change is further clarifying the intent of the code regarding accessibility by ensuring that for an equipment to be considered readily accessible no actions such as use of tools shall be necessary to access it. Impact(s) Improves safety - no negative impact.

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ARTICLE 110 Requirements for Electrical Installations

110.16 Arc-Flash Hazard Warning. Electrical equipment,

such as switchboards, switchgear, panelboards, industrial

control panels, meter socket enclosures, and motor control

centers, that are in other than dwelling units, and are likely

to require examination, adjustment, servicing, or mainte-

nance while energized, shall be field or factory marked to

warn qualified persons of potential electric arc flash haz-

ards. The marking shall meet the requirements in 110.21(B)

and shall be located so as to be clearly visible to qualified

persons before examination, adjustment, servicing, or

Change Description: Included factory marking as an acceptable method for warning about a potential arc-flash hazard. This change eliminates a need for adding a redundant arc-flash hazard warning label in the field for equipment already marked by the manufacturer. Impact(s) : No negative impact.

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maintenance of the equipment.

110.26 Spaces About Electrical Equipment.

(3) Personnel Doors. Where equipment rated 1200800 A or more that contains overcurrent devices, switching devices, or control devices is installed and there is a personnel door(s) intended for entrance to and egress from the working space less than 7.6 m (25 ft) from the nearest edge of the working space, the door(s) shall open in the direction of egress and be equipped with listed panic

bars, pressure plates, or other devices that are normally latched but open under simple pressure.hardware.

(E) Dedicated Equipment Space.

(2) Outdoor.

(b) Dedicated Equipment Space. The space equal to

the width and depth of the equipment, and extending from

grade to a height of 1.8 m (6 ft) above the equipment, shall be

dedicated to the electrical installation. No piping or other

equipment foreign to the electrical installation shall be

located in this zone.

Change Description: Lowered the ampacity of equipment from 1200A to 800A for which the specific requirements for the personnel door apply. This lowers the exposure of a worker in case of an arc flash in the equipment. Also, added requirements for dedicated equipment space in outdoor applications, which was missing from the code. This change allows enforcement of safe installation of equipment, regardless of its location. Impact(s) : Improves safety - no negative impact.

2

110.27 Guarding of Live Parts.

(A) Live Parts Guarded Against Accidental Contact.

(4) By elevation above the floor or other working surface as

shown in 110.27(A)(4)(a) or (b) below:

a. A minimum of 2.5 m (8 ft) or more above the floor or

other working surface.for 50 to 300 volts

b. A minimum of 2.6 m (81⁄2 ft) for 301 to 600 volts

Change Description: Increased elevation of live parts of equipment operating at voltages between 301 V and 600V. This coordinates the clearance requirements with the National Electrical Safety Code, 124A3 and Table 124-1. Impact(s) : Improves safety - no negative impact.

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ARTICLE 200 Use and Identification of Grounded Conductors



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200.4 Neutral Conductors. Neutral conductors shall be

installed in accordance with 200.4(A) and (B)

(A) Installation. Neutral conductors shall not be used for

more than one branch circuit, for more than one multiwire

branch circuit, or for more than one set of ungrounded feeder

conductors unless specifically permitted elsewhere in this

Code.

(B) Multiple Circuits. Where more than one neutral con-

ductor associated with different circuits is in an enclosure,

grounded circuit conductors of each circuit shall be identi-

fied or grouped to correspond with the ungrounded circuit

conductor(s) by wire markers, cable ties, or similar means

in at least one location within the enclosure.

Exception No. 1: The requirement for grouping or identi-

fying shall not apply if the branch-circuit or feeder conduc-

tors enter from a cable or a raceway unique to the circuit

that makes the grouping obvious.

Exception No. 2: The requirement for grouping or identi-

fying shall not apply where branch-circuit conductors pass

though a box or conduit body without a loop as described

in 314.16(B)(1) or without a splice or termination.

Change Description: This new provision in the code requires identification and grouping of the neutral conductor with ungrounded conductor of each circuit in an enclosure, following similar requirement in Section 210.4(D), but expanding it to all enclosures. Impact(s) : Improves safety – no negative impact.

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ARTICLE 210 Branch Circuits

210.4 Multiwire Branch Circuits.

(A) General.

(D) Grouping. The ungrounded and grounded circuit con-

ductors of each multiwire branch circuit shall be grouped

by cable ties or similar means in at least one location within

the panelboard or other point of origination.

Exception: The requirement for grouping shall not apply if

the circuit enters from a cable or raceway unique to the

circuit that makes the grouping obvious or if the conductors

are identified at their terminations with numbered wire

Change Description: This change further clarifies the intent that the grounded and ungrounded conductors shall be identifiable and allows an exception to the grouping rule for conductors identified at the terminations. Impact(s) : No negative impact.

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markers corresponding to the appropriate circuit number .

210.5 Identification for Branch Circuits

(C) Identification of Ungrounded Conductors.

(2) Branch Circuits Supplied From Direct-Current Sys-

tems. Where a branch circuit is supplied from a dc system

operating at more than 50 volts, each ungrounded conduc-

tor of 4 AWG or larger shall be identified by polarity at all

termination, connection, and splice points by marking tape,

tagging, or other approved means; each ungrounded con-

ductor of 6 AWG or smaller shall be identified by polarity

at all termination, connection, and splice points in compli-

ance with 210.5(C)(2)(a) and (b). The identification meth-

ods utilized for conductors originating within each branch-

circuit panelboard or similar branch-circuit distribution

equipment shall be documented in a manner that is readily

available or shall be permanently posted at each branch-

circuit panelboard or similar branch-circuit distribution

equipment.

(a) Positive Polarity, Sizes 6 AWG or Smaller. Where the

positive polarity of a dc system does not serve as the

connection point for the grounded conductor, each positive

ungrounded conductor shall be identified by one of the

following means:

(1) A continuous red outer finish

(2) A continuous red stripe durably marked along the con-

ductor’s entire length on insulation of a color other than

green, white, gray, or black

(3) Imprinted plus signs (+) or the word POSITIVE or

POS durably marked on insulation of a color other than green,

white, gray, or black, and repeated at intervals not exceeding

610 mm (24 in.) in accordance with 310.120(B)

(b) Negative Polarity, Sizes 6 AWG or Smaller. Where the

negative polarity of a dc system does not serve as the

connection point for the grounded conductor, each negative

ungrounded conductor shall be identified by one of the

following means:

Change Description: This change was triggered by the re-emergence of direct current (DC) applications. This new section provides criteria for identification of conductors in DC applications. Impact(s) : No negative impact.

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(1) A continuous black outer finish

(2) A continuous black stripe durably marked along the

conductor’s entire length on insulation of a color other than

green, white, gray, or red

(3) Imprinted minus signs (–) or the word NEGATIVE or

NEG durably marked on insulation of a color other

than green, white, gray, or red, and repeated at intervals not

exceeding 610 mm (24 in.) in accordance with

310.120(B)

210.8 Ground-Fault Circuit-Interrupter Protection for

Personnel.

(B) Other Than Dwelling Units.

(3) Rooftops

Exception No. 1 to (3):Receptacles on rooftops shall not be

required to be readily accessible other than from the rooftop.

Change Description: Clarifies the intent that ground-fault circuit-interrupter type receptacles installed on rooftops need to be readily accessible only from the roof top. Impact(s) : No negative impact.

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210.13 Ground-Fault Protection of Equipment. Each

branch-circuit disconnect rated 1000 A or more and in-

stalled on solidly grounded wye electrical systems of more

than 150 volts to ground, but not exceeding 600 volts

phase-to-phase, shall be provided with ground-fault protec-

tion of equipment in accordance with the provisions of

230.95.

Change Description: This change expands the ground-fault protection (GFP) for equipment for branch circuits meeting the criteria of Section 230.95. This change is similar to an earlier change which introduced GFP for feeders (Section 215.10). Impact(s) : Improves safety – no negative impact.

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210.17 Electric Vehicle Branch Circuit. An outlet(s) in-

stalled for the purpose of charging electric vehicles shall be

supplied by a separate branch circuit. This circuit shall have

no other outlets.

Change Description: New provision requiring vehicle charging station to be fed from a dedicated circuit, with no other outlets on it. Impact(s) : No negative impact.

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II. Branch-Circuit Ratings

210.19 Conductors — Minimum Ampacity and Size.

(A) Branch Circuits Not More Than 600 Volts.

(1) General. Branch-circuit conductors shall have an am-

pacity not less than the maximum load to be served. Con-

ductors shall be sized to carry not less than the larger of

210.19(A)(1)(a) or (b).

(a) Where a branch circuit supplies continuous loads or

any combination of continuous and noncontinuous loads, the

minimum branch-circuit conductor size, before the ap-

plication of any adjustment or correction factors,size shall

have an allowable ampacity not less than the noncontinuous

load plus 125 percent of the continuous load.

(b) The minimum branch-circuit conductor size shall have an

allowable ampacity not less than the maximum load to be

served after the application of any adjustment or correction

factors.

Change Description: The new wording clarifies that there are two conditions for determining the minimum conductor size and that the conductor is selected to carry not less than the larger of both conditions. Impact(s) : Improves clarity of the code – no negative impact.

1

210.22 Permissible Loads, Individual Branch Circuits.

An individual branch circuit shall be permitted to supply

any load for which it is rated, but in no case shall the load

exceed the branch-circuit ampere rating.

Change Description: Separated Section 210.23 into two sections by adding Section 210.22, covering individual branch circuits. Impact(s) : No negative impact.

1

210.64 Electrical Service Areas. At least one 125-volt,

single-phase, 15- or 20-ampere-rated receptacle outlet shall be

installed within 15 m (50 ft) of the electrical service

equipment.

Change Description: New section added, requiring a receptacle (120V, 15A or 20A) outlet within 50’ of the service area. Impact(s) : Improves safety – no negative impact.

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ARTICLE 215 Feeders



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215.2 Minimum Rating and Size.

(A) Feeders Not More Than 600 Volts.

(1) General. Feeder conductors shall have an ampacity not

less than required to supply the load as calculated in Parts

III, IV, and V of Article 220. Conductors shall be sized to

carry not less than the larger of 215.2(A)(1)(a) or (b).

(a) Where a feeder supplies continuous loads or any

combination of continuous and noncontinuous loads, The

minimum feeder circuit conductor size, before the applica-

tion of any adjustment or correction factors, the minimum

feeder conductor size shall have an allowable ampacity not

less than the noncontinuous load plus 125 percent of the

continuous load.

(b) The minimum feeder conductor size shall have an

allowable ampacity not less than the maximum load to be

served after the application of any adjustment or correction

factors.

Change Description: The new wording clarifies that there are two conditions for determining the minimum conductor size and that the conductor is selected to carry not less than the larger of both conditions. Impact(s) : Improves clarity of the code – no negative impact.

1

215.12 Identification for Feeders.

(C) Identification of Ungrounded Conductors. Un-

grounded conductors shall be identified in accordance with

215.12(C)(1) or (C)(2), as applicable.

2) Feeders Supplied from Direct-Current Systems.

Where a feeder is supplied from a dc system operating at

more than 50 volts, each ungrounded conductor of 4 AWG

or larger shall be identified by polarity at all termination,

connection, and splice points by marking tape, tagging, or

other approved means; each ungrounded conductor of

6 AWG or smaller shall be identified by polarity at all

termination, connection, and splice points in compliance

with 215.12(C)(2)(a) and (b). The identification methods

utilized for conductors originating within each feeder pan-

elboard or similar feeder distribution equipment shall be

documented in a manner that is readily available or shall be

Change Description: This change was triggered by the re-emergence of direct current (DC) applications. This new section provides criteria for identification of conductors in DC applications. Impact(s) : No negative impact.

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permanently posted at each feeder panelboard or similar

feeder distribution equipment.

(a) Positive Polarity, Sizes 6 AWG or Smaller. Where

the positive polarity of a dc system does not serve as the

connection for the grounded conductor, each positive un-

grounded conductor shall be identified by one of the fol-

lowing means:

(1) A continuous red outer finish

(2) A continuous red stripe durably marked along the con-

ductor’s entire length on insulation of a color other than

green, white, gray, or black

(3) Imprinted plus signs (+) or the word POSITIVE or

POS durably marked on insulation of a color other than

green, white, gray, or black, and repeated at intervals not

exceeding 610 mm (24 in.) in accordance with 310.120(B)

(b) Negative Polarity, Sizes 6 AWG or Smaller. Where

the negative polarity of a dc system does not serve as the

connection for the grounded conductor, each negative un-

grounded conductor shall be identified by one of the fol-

lowing means:

(1) A continuous black outer finish

(2) A continuous black stripe durably marked along the

conductor’s entire length on insulation of a color other

than green, white, gray, or red

(3) Imprinted minus signs (–) or the word NEGATIVE or

NEG durably marked on insulation of a color other than

green, white, gray, or red, and repeated at intervals not

exceeding 610 mm (24 in.) in accordance with 310.120(B)

ARTICLE 220 Branch-Circuit, Feeder, and Service Calculations

220.12 Lighting Load for Specified Occupancies. A unit

load of not less than that specified in Table 220.12 for

occupancies specified therein shall constitute the minimum

lighting load. The floor area for each floor shall be calcu-

lated from the outside dimensions of the building, dwelling

unit, or other area involved. For dwelling units, the calcu-

Change Description: The new exception to calculating lighting loads was added to allow lighting loads to be calculated in accordance with local codes where power monitoring systems are in place.

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lated floor area shall not include open porches, garages, or

unused or unfinished spaces not adaptable for future use.

Exception: Where the building is designed and constructed

to comply with an energy code adopted by the local

authority, the lighting load shall be permitted to be

calculated at the values specified in the energy code where

the following conditions are met:

(1) A power monitoring system is installed that will pro-

vide continuous information regarding the total general

lighting load of the building.

(2) The power monitoring system will be set with alarm

values to alert the building owner or manager if the

lighting load exceeds the values set by the energy code.

(3) The demand factors specified in 220.42 are not applied

to the general lighting load.


ARTICLE 225 Outside Branch Circuits and Feeders

225.4 Conductor Covering. Where within 3.0 m (10 ft) of

any building or structure other than supporting poles or towers,

open individual (aerial) overhead conductors shall be insulated

or covered. for the nominal voltage.

Change Description: This change prohibits the use of bare conductors within 10’ from any building or structure, except poles or towers. Impact(s) : Improves safety – no negative impact.

2

225.11 Circuit Exits and Entrances. Where outside

branch and feeder circuits leave or enter a building, the

requirements of 230.52 and 230.54 shall apply.

225.11 Feeder and Branch-Circuit Conductors Enter-

ing, Exiting, or Attached to Buildings or Structures.

Feeder and branch-circuit conductors entering or exiting

buildings or structures shall be in installed in accordance

with the requirements of 230.52. Overhead branch circuits

and feeders attached to buildings or structures shall be in-

Change Description: Change the title and the text of this section to improve the clarity. Also, expanded this requirement to include other structures. Impact(s) : No negative impact.

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stalled in accordance with the requirements of 230.54.

225.17 Masts as Supports. Where a mast is Only feeder or

branch-circuit conductors specified within this section shall

be permitted to be attached to the feeder and/or branch-

circuit mast. Masts used for the support of final spans of

feeders or branch circuits, circuits shall be installed in

accordance with 225.17(A) and (B).

A) Strength. itThe mast shall be of adequate strength or be

supported by braces or guys to withstand safely the strain

imposed by the overhead drop. Where raceway-type masts

are used, all raceway fittings shall be identified for use with

masts. Only the feeder or branch-circuit conductors. Hubs

intended for use with a conduit that serves as a mast for

support of feeder or branch-circuit conductors specified within

this section shall be permitted to be attached to the feeder

and/or branch-circuit identified for use with a mast. (B) Attachment. Feeder and/or branch-circuit conductors

shall not be attached to a mast between a weatherhead or the

end of the conduit and a coupling where the coupling is

located above the last point of securement to the building or

other structure or is located above the building or other

structure.

Change Description: Text revised for clarity. Also, included a requirement for all components of a mast to be identified for use with a mast. In addition, put some restrictions on attaching conductors to a mast to ensure its structural integrity. Impact(s) : Improves safety – no negative impact.

2

225.27 Raceway Seal. Where a raceway enters a building

or structure from an underground distribution system, it

shall be sealed in accordance with 300.5(G). Spare or un-

used raceways shall also be sealed. Sealants shall be iden-

tified for use with the cable insulation, conductor insula-

tion, bare conductor, shield, or other components.

Change Description: Expanded the scope of this section to require compatibility of sealants with conductor insulation and with bare conductor material. Impact(s) : No negative impact.

2

225.36 Suitable for Service Equipment. Type. The dis-

connecting means specified in 225.31 shall be comprised of a Change Description: Revised to specifically identify acceptable disconnecting means

2



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circuit breaker, molded case switch, general-use switch, snap

switch, or other approved means. Where applied in

accordance with 250.32(B), Exception No. 1, the

disconnecting means shall be suitable for use as service

equipment.

and to clarify when a disconnecting means must be suitable for use as a service equipment. Also, eliminated exception allowing 3- and 4-way switches as disconnecting means because they would not provide a positive indication that a circuit was disconnected. Impact(s) : Improves safety - no negative impact.

II. Over 6001000 Volts.

225.52 Disconnecting Means.

(A) Location. A building or structure disconnecting means

shall be located in accordance with 225.32, or, if not readily

accessible, it shall be operable by mechanical linkage from a

readily accessible point. For multibuilding industrial installa-

tions under single management, it shall be permitted to be

electrically operated by a similarly locatedreadily accessible,

remote-control device in a separate building or structure.

(B) Type. Each building or structure disconnect shall si-

multaneously disconnect all ungrounded supply conductors

it controls and shall have a fault-closing rating not less than

the maximum available short-circuit current available at its

supply terminals.

Exception: Where the individual disconnecting means con-

sists of fused cutouts, the simultaneous disconnection of all

ungrounded supply conductors shall not be required if there is

a means to disconnect the load before opening the cutouts. A

permanent legible sign shall be installed adjacent to the fused

cutouts indicating the above requirement. and shall read DIS-

CONNECT LOAD BEFORE OPENING CUTOUTS.

Change Description: This change allows operation of disconnecting means over 1000V using remote-control device from a readily accessible location. Impact(s) : No negative impact.

2

225.56 Inspections and Tests.

(A) Pre-Energization and Operating Tests. The com-

plete electrical system design, including settings for protec-

Change Description: Defined in more detail the required pre-energization and

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tive, switching, and control circuits, shall be prepared in

advance and made available on request to the authority

having jurisdiction and shall be performance tested when

first installed on-site. Each protective, switching, and con-

trol circuit shall be adjusted in accordance with the recom-

mendations of the protective device studysystem design

and tested by actual operation using current injection or

equivalent methods as necessary to ensure that each and

every such circuit operates correctly to the satisfaction of

the authority having jurisdiction.

(B) Type. Each building or structure disconnect shall si-

multaneously disconnect all ungrounded supply conductors

it controls and shall have a fault-closing rating not less than

the maximum available short-circuit current available at its

supply terminals.

Exception: Where the individual disconnecting means con-

sists of fused cutouts, the simultaneous disconnection of all

ungrounded supply conductors shall not be required if there is a

means to disconnect the load before opening the cutouts. A

permanent legible sign shall be installed adjacent to the fused

cutouts indicating the above requirement. and shall read DIS-

CONNECT LOAD BEFORE OPENING CUTOUTS.

operating tests for systems over 1000 V. Also, clarified what wording is to be provided for the warning sign to be located adjacent to a fuse cutout. Impact(s) : No negative impact.

225.70 Substations. Change Description: Relocated requirements to Article 490, covering equipment over 1000 V. Impact(s) : No negative impact.

1

ARTICLE 230 Services



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230.6 Conductors Considered Outside the Building.

Conductors shall be considered outside of a building or

other structure under any of the following conditions:

(5) Where installed in overhead service masts on the out-

side surface of the building traveling through the cave of

that building within rigid metal conduit (Type RMC) or

intermediate metal conduit (Type IMC) to meet the

requirements of 230.24. used to accommodate the clearance

requirements in 230.24 and routed directly through an eave

but not a wall of a building.

Change Description: The change defines as outside the building RMC or IMC raceways passing through an eave but not a wall of a building. This limits this provision of the code to heavy wall steel raceways. Impact(s) : Improves safety - no negative impact.

2

230.28 Service Masts as Supports. Where a service mast

is used for the support of service-drop conductors, it shall

be of adequate strength or be supported by braces or guys

to withstand safely the strain imposed by the service drop.

Where raceway-type service masts are used, all raceway

fittings shall be identified for use with service masts. Only

power service-drop conductors shall be permitted to be at-

tached to a service mast. Only power service-drop or over-

head service conductors shall be permitted to be attached to

a service mast. Service masts used for the support of

service-drop or overhead service conductors shall be in-

stalled in accordance with 230.28(A) and (B).

(A) Strength. The service mast shall be of adequate

strength or be supported by braces or guys to withstand

safely the strain imposed by the service-drop or overhead

service conductors. Hubs intended for use with a conduit

that serves as a service mast shall be identified for use with

service-entrance equipment.

(B) Attachment. Service-drop or overhead service con-

ductors shall not be attached to a service mast between a

weatherhead or the end of the conduit and a coupling,

where the coupling is located above the last point of secure-

ment to the building or other structure or is located above

the building or other structure.

Change Description: Text revised for clarity. Also, included a requirement for all components of a mast to be identified for use with service equipment. In addition, put some restrictions on attaching conductors to a mast to ensure its structural integrity. Impact(s) : Improves safety – no negative impact.

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230.42 Minimum Size and Rating.

A) General. The ampacity of the service-entrance con-

ductors before the application of any adjustment or correc-

tion factors shall not be less than either 230.42(A)(1),

(A)(2), or (A)(23). Loads shall be determined in accordance

with Part III, IV, or V of Article 220 as applicable. Ampacity

shall be determined from 310.15. The maximum allowable

current of busways shall be that value for which the busway

has been listed or labeled.

(1) The sum of the noncontinuous loads plus 125 percent of

continuous loads

Exception: Grounded conductors that are not connected to an

overcurrent device shall be permitted to be sized at

100 percent of the continuous and noncontinuous load.

(2) The sum of the noncontinuous load plus the continuous

load after the application of any adjustment or correction

factors.

(2)(3)The sum of the noncontinuous load plus the continu-

ous load if the service-entrance conductors terminate in an

overcurrent device where both the overcurrent device and

its assembly are listed for operation at 100 percent of their

rating.

Change Description: Companion to changes to Sections 210.19(A)(1) and 215.2(A)(1). The new wording clarifies that there are two conditions for determining the minimum conductor size and that the conductor is selected to carry not less than the larger of both conditions. Impact(s) : Improves clarity – no negative impact.

1

230.44 Cable Trays. Cable tray systems shall be

permitted to support service-entrance conductors.

Cable trays used to support service-entrance

conductors shall contain only service-entrance

conductors and shall be limited to the fol-

lowing methods:

(1) Type SE cable

(2) Type MC cable

(3) Type MI cable

(4) Type IGS cable

(5) Single thermoplastic-insulated conductors 1/0 and

larger with CT rating.

Change Description: This change provides label spacing requirements, consistent with Section 392.18(H) for cable trays containing high voltage conductors. Impact(s) : Provides consistency – no negative impact.

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Such cable trays shall be identified with permanently

affixed labels with the wording “Service-Entrance Conduc-

tors.” The labels shall be located so as to be visible after

installation and placedwith a spacing not to exceed 3 m

(10 ft) so that the service-entrance conductors are able to be

readily traced through the entire length of the cable tray.

230.82 Equipment Connected to the Supply Side of Ser-

vice Disconnect.

(3) Meter disconnect switches nominally rated not in ex-

cess of 600 volts1000 V that have a short-circuit current

rating equal to or greater than the available short- circuit

current, provided that all metal housings and service

enclosures are grounded in accordance with Part VII and

bonded in accordance with Part V of Ar- ticle 250. A meter

disconnect switch shall be capable of interrupting the load

served. A meter disconnect shall be legibly field marked

on its exterior in a manner suitable for the environment as

follows:

METER DISCONNECT NOT SERVICE EQUIPMENT

Change Description: Added a labeling requirement for meter disconnect to ensure a clear understanding that this particular disconnect is not a service disconnect. Impact(s) : Improves safety - no negative impact.

2

ARTICLE 240 Overcurrent Protection

240.21 Location in Circuit.

(B) Feeder Taps.

(1) Taps Not over 3 m (10 ft) Long. If the length of the tap

conductors does not exceed 3 m (10 ft) and the tap conductors

comply with all of the following:

(1) The ampacity of the tap conductors is

a. Not less than the combined calculated loads on

the circuits supplied by the tap conductors, and

b. Not less than the rating of the equipment

containing an overcurrent device(s) supplied by

the tap conductors or not less than the rating of

the overcurrent protective device at the

termination of the tap conductors.

Change Description: This new exception allows use of manufacturer specified wire size in lieu of applying a tap rule for conductors supplying listed equipment, such as surge protective device. Impact(s) : No negative impact.

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Exception to b: Where listed equipment, such as a surge

protective device(s) [SPD(s)], is provided with specific in-

structions on minimum conductor sizing, the ampacity of

the tap conductors supplying that equipment shall be per-

mitted to be determined based on the manufacturer’s

instructions.

(C) Transformer Secondary Conductors.

(10 ft) Long. If the length of secondary conductor does

not exceed 3 m (10 ft) and complies with all of the

following:

(1) The ampacity of the secondary

conductors is

a. Not less than the combined calculated loads on

the circuits supplied by the secondary

conductors, and

b. Not less than the rating of the equipment

containing an overcurrent device(s) supplied by

the secondary conductors or not less than the

rating of the overcurrent protective device at

the termination of the secondary conductors.

Exception: Where listed equipment, such as a surge protec-

tive device(s) [SPD(s)], is provided with specific instruc-

tions on minimum conductor sizing, the ampacity of the tap

conductors supplying that equipment shall be permitted to

be determined based on the manufacturer’s instructions.

240.87 Noninstantaneous Trip.Arc Energy Reduction.

Where the highest continuous current trip setting for which

the actual overcurrent device installed in a circuit breaker is

used without an instantaneous trip,rated or can be adjusted is

1200 A or higher, 240.87(A) and (B) shall apply.

(B) Method to Reduce Clearing Time. Where a circuit

breaker is utilized without an instantaneous trip, oneOne of

the following or approved equivalent means shall be pro-

vided:

Change Description: This change provides more clarity and usability to this requirement and adds energy-reducing active arc flash mitigation system as one of the methods of reducing arc flash energy. Impact(s) : No negative impact.

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(4) Energy-reducing active arc flash mitigation system

(5) An approved equivalent means

ARTICLE 250 Grounding and Bonding

250.10 Protection of Ground Clamps and Fittings.

Ground clamps or other fittings shall be approved for gen-

eral use without protection or shall be protected from ex-

posed to physical damage as indicated in (1) or (2) as fol-

lows:

(1) In installations where they are not likely to be damaged

(2) Where shall be enclosed in metal, wood, or equivalent

protective coveringcovering.

Change Description: Change to the wording provides more clarity. Impact(s) : No negative impact.

1

250.21 Alternating-Current Systems of 50 Volts to Less

Than 1000 Volts Not Required to Be Grounded. C) Marking. Ungrounded systems shall be legibly

marked “Caution: Ungrounded System Operating —

Volts Between Conductors” at the source or first discon-

necting means of the system. The marking shall be of suf-

ficient durability to withstand the environment involved.

Change Description: Added a requirement for labeling of ungrounded systems to include operating voltage between conductors, consistent with requirement in 408.3(F)(2). Impact(s) : Improves safety – no negative impact.

2

250.24 Grounding Service-Supplied Alternating-

Current Systems.

(C) Grounded Conductor Brought to Service Equipment.

(1) Sizing for a Single Raceway. The grounded conductor

shall not be smaller than the required grounding electrode

conductor specified in Table 250.66250.102(C)(1). but shall

not be required to be larger than the largest ungrounded

service-entrance conductor(s). In addition, for sets of un-

grounded service-entrance conductors larger than 1100 kc-

mil copper or 1750 kcmil aluminum, the grounded conduc-

tor shall not be smaller than 121⁄2 percent of the circular mil

area of the largest set of service-entrance ungrounded con-

Change Description: A new Table 250.102(C)(1) was added for sizing grounded conductors and bonding jumpers rather than Table 250.66. References to this new table and the existing Table 250.66 were revised throughout Article 250. Impact(s) : No negative impact.

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ductor(s).

250.28 Main Bonding Jumper and System Bonding

Jumper.

(D) Size.

1) General. Main bonding jumpers and system bonding

jumpers shall not be smaller than the sizes shown in Table

250.66. Where the supply conductors are larger than 1100

kcmil copper or 1750 kcmil aluminum, the bonding jumper

shall have an area that is not less than 121⁄2 percent of the

area of the largest phase conductor except that, where the

phase conductors and the bonding jumper are of different

materials (copper or aluminum), the minimum size of the

bonding jumper shall be based on the assumed use of phase

conductors of the same material as the bonding jumper and

with an ampacity equivalent to that of the installed phase

conductors. Main bonding jumpers and system bonding

jumpers shall not be smaller than specified in Table

250.102(C)(1).


1

250.30 Grounding Separately Derived Alternating-

Current Systems. In addition to complying with

250.30(A) for grounded systems, or as provided in

250.30(B) for ungrounded systems, separately derived sys-

tems shall comply with 250.20, 250.21, 250.22, and

250.26.250.22, or 250.26, as applicable. Multiple sepa-

rately derived systems that are connected in parallel shall

be installed in accordance with 250.30.

Change Description: The added text provides requirements for multiple separately derived systems operating in parallel. Impact(s) : No negative impact.

2


Current Systems.

(A) Grounded Systems.

(1) System Bonding Jumper.

Exception No. 2: A If a building or structure is supplied by

a feeder from an outdoor transformer, a system bonding

Change Description: The revised text provides for the limited case where the grounded conductor can be bonded at the source of a separately derived system and in a building or structure served and continues to prohibit parallel paths. This limits the application of this exception to buildings and structures supplied by a feeder from an outdoor transformer.

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jumper at both the source and the first disconnecting means

shall be permitted if doing so does not establish a parallel

path for the grounded conductor. If a grounded conductor

is used in this manner, it shall not be smaller than the size

specified for the system bonding jumper but shall not be

required to be larger than the ungrounded conductor(s).

For the purposes of this exception, connection through

the earth shall not be considered as providing a parallel

path.



Current Systems.


(2) Supply-Side Bonding Jumper.

Exception: A supply-side bonding jumper shall not be re-

quired between enclosures for installations made in com-

pliance with 250.30(A)(1), Exception No. 2.

Change Description: A companion change to Section 250.30(A)(1), Exception No.2, allowing grounded conductor as a means of bonding enclosures. Impact(s) : No negative impact.

2


Current Systems.


(3) Grounded Conductor.

a) Sizing for a Single Raceway. The grounded conduc-

tor shall not be smaller than the required grounding electrode

conductor specified in Table 250.66250.102(C)(1). but shall

not be required to be larger than the largest derived un-

grounded conductor(s). In addition, for sets of derived un-

grounded conductors larger than 1100 kcmil copper or 1750

kcmil aluminum, the grounded conductor shall not be smaller

than 121⁄2 percent of the circular mil area of the largest set of

derived ungrounded conductors.


1

250.32 Buildings or Structures Supplied by a Feeder(s)

or Branch Circuit(s). Change Description: 2



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(B) Grounded Systems.

(1) Supplied by a Feeder or Branch Circuit.

Exception No. 2: If system bonding jumpers are installed

in accordance with 250.30(A)(1), Exception No. 2, the

feeder grounded circuit conductor at the building or

structure served shall be connected to the equipment

grounding conductors, grounding electrode conductor, and

the enclsure for the first disconnecting means.

The added exception provides requirements for the grounded conductor in a building or structure served by a feeder from an outdoor transformer separately derived system installed in accordance with 250.30(A)(1) Exception No. 2. Impact(s) : No negative impact.

250.36 High-Impedance Grounded Neutral Systems.

(F) Grounding Electrode Conductor Connection Loca-

tion. The For services or separately derived systems, the

grounding electrode conductor shall be connected at any point

from the grounded side of the grounding impedance to the

equipment grounding connection at the service equipment or

the first system disconnecting means of a separately derived

system.

Change Description: The change clarifies the intent of this section which requires establishing of the fault-current path from the system back to the source of the separately derived system. Impact(s) : No negative impact.

1

250.62 Grounding Electrode Conductor Material. The

grounding electrode conductor shall be of copper, alumi-

num, copper-clad aluminum, or copper-clad aluminum. the

items as permitted in 250.68(C). The material selected shall

be resistant to any corrosive condition existing at the instal-

lation or shall be protected against corrosion. The conduc-

torConductors of the wire type shall be solid or stranded,

insulated, covered, or bare.

Change Description: Clarified the intent that materials identified in Section 250.68(C) are acceptable as grounding electrode conductors (e.g. water piping, metal structural frame). Impact(s) : No negative impact.

2

250.64 Grounding Electrode Conductor Installation.

(B) Securing and Protection Against Physical Damage.

Grounding electrode conductors and grounding electrode

bonding jumpers shall not be required to comply with 300.5.

Change Description: The added sentence clarifies that grounding electrode conductors or grounding electrode bonding jumpers are not subject to the burial depth requirements found in Section 300.5. Impact(s) : No negative impact.

1



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(D) Service Building or Structure with Multiple Discon-

necting Means in Separate Enclosures. IfFor a service

consists of more than a single enclosure as permitted in

230.71(A),or feeder with two or more disconnecting means

in separate enclosures supplying a building or structure, the

grounding electrode connections shall be made in accor-

dance with 250.64(D)(1), (D)(2), or (D)(3).

(2) Individual Grounding Electrode Conductors. A

grounding electrode conductor shall be connected between

the grounded conductor in each service equipment discon-

necting means enclosure and the grounding electrode sys-

tem.grounding electrode system and one or more of the

following, as applicable:

(1) Grounded conductor in each service equipment discon-

necting means enclosure

(2) Equipment grounding conductor installed with the

feeder

(3) Supply-side bonding jumper

Each grounding electrode conductor shall be sized in

accordance with 250.66 based on the service-entrance or

feeder conductor(s) supplying the individual service dis-

connecting means.

(3) Common Location. A grounding electrode conductor

shall be connected to the grounded service conductor(s) in

a wireway or other accessible enclosure on the supply side

of the service disconnecting means.means to one or more of

the following, as applicable:

(1) Grounded service conductor(s)

(2) Equipment grounding conductor installed with the

feeder

(3) Supply-side bonding jumper

Change Description: This revised language incorporates clarification to ensure that this section can be applied to both, building services and buildings fed by one or more feeders. Impact(s) : No negative impact.

2



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(E) Raceways and Enclosures for Grounding Electrode

Conductors.

(1) General. Ferrous metal raceways and enclosures for

grounding electrode conductors shall be electrically con-

tinuous from the point of attachment to cabinets or equip-

ment to the grounding electrode and shall be securely fas-

tened to the ground clamp or fitting. NonferrousFerrous

metal raceways and enclosures shall not be required to be

electrically continuous. Ferrous metal enclosures that are

not physically continuous from cabinets or equipment-

bonded at each end of the raceway or enclosure to the

grounding electrode shall be made electrically continuous

by bonding each end of the raceway or enclosure to the

grounding electrode conductor. or grounding electrode con-

ductor. Nonferrous metal raceways and enclosures shall not

be required to be electrically continuous.

(2) Methods. Bonding methods shall be in compliance

with 250.92(B) for installations at service equipment loca-

tions and with and ensured by one of the methods in

250.92(B)(2) through (B)(4) for other than service equip-

ment locations shall apply at each end and to all intervening

ferrous raceways, boxes, and enclosures between the cabi-

nets or equipment and the grounding electrode.(B)(4).

Change Description: This change affirms that nonferrous metal enclosures are not required to be electrically continuous or bonded. Impact(s) : No negative impact.

1

250.66 Size of Alternating-Current Grounding Elec-

trode Conductor.

A) Connections to a Rod, Pipe, or Plate Electrode(s).

Where the grounding electrode conductor is connected to a

single or multiple rod, pipe, or plate electrode(s), or any combination thereof, as permitted in 250.52(A)(5) or (A)(7), that portion of the conductor that is the sole connection to the grounding electrode(s) shall not be required to

be larger than 6 AWG copper wire or 4 AWG aluminum wire.

B) Connections to Concrete-Encased Electrodes. Where the

Change Description: Clarification added for the “sole connection” provisions. Impact(s) : No negative impact.

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grounding electrode conductor is connected to a single or

multiple concrete-encased electrode(s) as permitted in

250.52(A)(3), that portion of the conductor that is the sole

connection to the grounding electrode(s) shall not be re-

quired to be larger than 4 AWG copper wire.

250.68 Grounding Electrode Conductor and Bonding

Jumper Connection to Grounding Electrodes.

(C) Metallic Water Pipe and Structural Metal.Ground-

ing Electrode Connections. Grounding electrode conduc-

tors and bonding jumpers shall be permitted to be

connected at the following locations and used to extend

the connection to an electrode(s):

(2) The metal structural frame of a building that is directly

connected to a grounding electrode as specified in

250.52(A)(2) or 250.68(C)(2)(a), (b), or (c) shall be permitted to be used as a bonding conductor to inter-

connect electrodes that are part of the grounding electrode

system, or as a grounding electrode conductor.

a. By connecting the structural metal frame to the re-

inforcing bars of a concrete-encased electrode, as

provided in 250.52(A)(3), or ground ring as pro-

vided in 250.52(A)(4)

b. By bonding the structural metal frame to one or

more of the grounding electrodes, as specified in

250.52(A)(5) or (A)(7), that comply with

250.53(A)(2)

c. By other approved means of establishing a connec-

tion to earth

(3) A concrete-encased electrode of either the conductor

type, reinforcing rod or bar installed in accordance with

250.52(A)(3) extended from its location within the concrete to an accessible location above the concrete shall be permitted.

Change Description: Removed prescriptive language limiting the use of metal structural frame as a bonding conductor. Also, recognized a common practice of extending rebar outside the concrete as an allowable grounding electrode conductor connection point. Impact(s) : No negative impact.

2

250.102 Bonding Conductors and Jumpers. Change Description: 1



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(C) Size — Supply-Side Bonding Jumper.

(1) Size for Supply Conductors in a Single Raceway or

Cable. The supply-side bonding jumper shall not be smaller than the sizes shown specified in Table

250.66250.102(C)(1). for grounding electrode conductors.

Where the ungrounded supply conductors are larger than

1100 kcmil copper or 1750 kcmil aluminum, the supply-

side bonding jumper shall have an area not less than 121⁄2

percent of the area of the largest set of ungrounded supply

conductors.

(2) Size for Parallel Conductor Installations in Two or

More Raceways. Where the ungrounded supply conduc-

tors are paralleled in two or more raceways or cables, and

an individual supply-side bonding jumper is used for bond-

ing these raceways or cables, the size of the supply-side

bonding jumper for each raceway or cable shall be selected

from Table 250.66250.102(C)(1) based on the size of the

ungrounded supply conductors in each raceway or cable. A

single supply-side bonding jumper installed for bonding

two or more raceways or cables shall be sized in accor-

dance with 250.102(C)(1).

(3) Different Materials. Where the ungrounded supply

conductors and the supply-side bonding jumper are of dif-

ferent materials (copper or aluminum), the minimum size

of the supply-side bonding jumper shall be based on the

assumed use of ungrounded conductors of the same mate-

rial as the supply-side bonding jumper and with an ampac-

ity equivalent to that of the installed ungrounded supply

conductors.

A new Table 250.102(C)(1) was added for sizing grounded conductors and bonding jumpers rather than Table 250.66. References to this new table and the existing Table 250.66 were revised throughout Article 250. Impact(s) : No negative impact.

Table 250.102(C) Grounded Conductor, Main Bonding

Jumper, System Bonding Jumper, and Supply-Side

Bonding Jumper for Alternating-Current Systems

The full Table not included for brevity.

Change Description: This new table and corresponding changes to related sections are provided to simplify the sizing requirements for fault carrying conductors that are not sized using Table 250.122. Presently, multiple sections such as for main bonding jumpers, system

1



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bonding jumpers, supply side bonding jumpers and grounded conductors refer to Table 250.66 for sizing the conductor or jumper. Impact(s) : No negative impact.

250.104 Bonding of Piping Systems and Exposed Struc-

tural Steel.Metal.

(B) Other Metal Piping.

The bonding conductor(s) or jumper(s) shall be sized in

accordance with 250.122, using the rating of the circuit that is

likely to energize the piping system(s). The equipment

grounding conductor for the circuit that is likely to energize

the piping shall be permitted to serve as the bonding means.

The points of attachment of the bonding jumper(s) shall be

accessible.

Change Description: Editorial change clarifying the intent. Impact(s) : No negative impact.

1

250.119 Identification of Equipment Grounding Con-

ductors.

Exception No. 2: Flexible cords having an integral insula-

tion and jacket without an equipment grounding conductor

shall be permitted to have a continuous outer finish that is

green.

Exception No. 3: Conductors with green insulation shall be

permitted to be used as ungrounded signal conductors

where installed between the output terminations of traffıc

signal control and traffıc signal indicating heads. Signaling

circuits installed in accordance with this exception shall

include an equipment grounding conductor in accordance

with 250.118. Wire-type equipment grounding conductors

shall be bare or have insulation or covering that is green

with one or more yellow stripes.

Change Description: Editorial change clarifying the intent. Impact(s) : No negative impact.

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250.121 Use of Equipment Grounding Conductors. An

equipment grounding conductor shall not be used as a

grounding electrode conductor.

Exception: A wire-type equipment grounding conductor in-

stalled in compliance with 250.6(A) and the applicable re-

quirements for both the equipment grounding conductor

and the grounding electrode conductor in Parts II, III, and

VI of this article shall be permitted to serve as both an

equipment grounding conductor and a grounding electrode

conductor.

Change Description: The code making panel recognized that restricting the use of a wire-type equipment grounding conductor for both the equipment grounding conductor and grounding electrode conductor was not justified when it was introduced in 2011 edition of NEC. However, this restriction remains in effect for all types of equipment grounding conductors identified in Section 250.118 other than wire-type conductor. Impact(s) : No negative impact.

2

250.130 Equipment Grounding Conductor Connec-

tions.

(C) Nongrounding Receptacle Replacement or Branch

Circuit Extensions.

(4) An equipment grounding conductor that is part of an-

other branch circuit that originates from the enclosure

where the branch circuit for the receptacle or branch circuit

originates

Change Description: This addition improves the grounding of nongrounding receptacle replacement or circuit extensions by allowing the most direct path back to the enclosure where the branch circuit originates. Impact(s) : Improves safety - no negative impact.

2

VIII. Direct-Current Systems

250.162 Direct-Current Circuits and Systems to Be

Grounded.

(A) Two-Wire, Direct-Current Systems. A 2-wire, dc

system supplying premises wiring and operating at greater

than 5060 volts but not greater than 300 volts shall be

grounded.

Exception No. 1: A system equipped with a ground detec-

tor and supplying only industrial equipment in limited ar-

eas shall not be required to be grounded where installed

adjacent to or integral with the source of supply.

Change Description: This change is related to the re-emergence of direct current applications with 50 V storage batteries and takes into account differences in the battery chemistries, with voltages potentially slightly exceeding 50 V threshold. It also aligns this voltage level with Chapter 9, Table 11(B) 60 V break point. Impact(s) : No negative impact.

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250.166 Size of the Direct-Current Grounding Elec-

trode Conductor. The size of the grounding electrode con-

ductor for a dc system shall be as specified in 250.166(A)

and (B), except as permitted by through 250.166(C)

through (E). The grounding electrode conductor for a dc

system shall meet the sizing requirements in this section

but shall not be required to be larger than 3/0 copper or 250

kcmil aluminum.

Change Description: This change fills the gap regarding the required maximum size of a grounding electrode conductor in a DC system. It brings this section into alignment with the similar requirements which exist for AC systems. Impact(s) : No negative impact.

2

250.167 Direct-Current Ground-Fault Detection.

(A) Ungrounded Systems. Ground-fault detection sys-

tems shall be required for ungrounded systems.

(B) Grounded Systems. Ground-fault detection shall be

permitted for grounded systems.

(C) Marking. Direct-current systems shall be legibly

marked to indicate the grounding type at the dc source or

the first disconnecting means of the system. The marking

shall be of sufficient durability to withstand the environ-

ment involved.

Change Description: This new section provides details for ground-fault detection and aligns the requirements with the requirements found in NFPA 70E.


2

250.186 Ground-Fault Circuit Conductor Brought to

Service Equipment. (A) Systems with a Grounded Conductor at the Service

Point. Where an ac system operating at over 1000 volts is

grounded at any point and is provided with a grounded

conductor at the service point, a grounded conductor(s)

shall be installed and routed with the ungrounded conduc-

tors to each service disconnecting means and shall be con-

nected to each disconnecting means grounded conductor(s)

terminal or bus. A main bonding jumper shall connect the

grounded conductor(s) to each service disconnecting means

enclosure. The grounded conductor(s) shall be installed in

accordance with 250.186(A)(1) through (A)(4). The size of

Change Description: This new section provides requirements for a conductor providing a low impedance path for ground fault currents to return to the source on systems over 1000 V. It aligns the requirements for over 1000 V with requirements found in Section 250.24(C) for 1000 V and below systems regarding ground fault return path. Impact(s) : No negative impact.

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the solidly grounded circuit conductor(s) shall be the larger

of that determined by 250.184 or 250.186(A)(1) or (A)(2).

Exception: Where two or more service disconnecting

means are located in a single assembly listed for use as

service equipment, it shall be permitted to connect the

grounded conductor(s) to the assembly common grounded

conductor(s) terminal or bus. The assembly shall include a

main bonding jumper for connecting the grounded conduc-

tor(s) to the assembly enclosure.

(1) Sizing for a Single Raceway or Overhead Conduc-

tor. The grounded conductor shall not be smaller than the

required grounding electrode conductor specified in Table

250.66 but shall not be required to be larger than the largest

ungrounded service-entrance conductor(s). In addition, for

sets of ungrounded service-entrance conductors larger than

1100 kcmil copper or 1750 kcmil aluminum, the grounded

conductor shall not be smaller than 121⁄2 percent of the

circular mil area of the largest set of service-entrance un-

grounded conductor(s).

(2) Parallel Conductors in Two or More Raceways or

Overhead Conductors. If the ungrounded service-entrance

conductors are installed in parallel in two or more raceways

or as overhead parallel conductors, the grounded conduc-

tors shall also be installed in parallel. The size of the

grounded conductor in each raceway or overhead shall be

based on the total circular mil area of the parallel un-

grounded conductors in the raceway or overhead, as indi-

cated in 250.186(A)(1), but not smaller than 1/0 AWG.

Informational Note: See 310.10(H) for grounded conductors connected in parallel.

(3) Delta-Connected Service. The grounded conductor of

a 3-phase, 3-wire delta service shall have an ampacity not

less than that of the ungrounded conductors.

(4) Impedance Grounded Neutral Systems. Impedance

grounded neutral systems shall be installed in accordance

with 250.187.



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(B) Systems Without a Grounded Conductor at the Ser-

vice Point. Where an ac system operating at greater than

1000 volts is grounded at any point and is not provided

with a grounded conductor at the service point, a supply-

side bonding jumper shall be installed and routed with the

ungrounded conductors to each service disconnecting

means and shall be connected to each disconnecting means

equipment grounding conductor terminal or bus. The

supply-side bonding jumper shall be installed in accordance

with 250.186(B)(1) through (B)(3).

Exception: Where two or more service disconnecting

means are located in a single assembly listed for use as

service equipment, it shall be permitted to connect the

supply-side bonding jumper to the assembly common

equipment grounding terminal or bus.

(1) Sizing for a Single Raceway or Overhead Conduc-

tor. The supply-side bonding jumper shall not be smaller

than the required grounding electrode conductor specified

in Table 250.66 but shall not be required to be larger than

the largest ungrounded service-entrance conductor(s). In

addition, for sets of ungrounded service-entrance conduc-

tors larger than 1100 kcmil copper or 1750 kcmil alumi-

num, the supply-side bonding jumper shall not be smaller

than 121⁄2 percent of the circular mil area of the largest set

of service-entrance ungrounded conductor(s).

(2) Parallel Conductors in Two or More Raceways or

Overhead Conductors. If the ungrounded service-entrance

conductors are installed in parallel in two or more raceways

or overhead conductors, the supply-side bonding jumper

shall also be installed in parallel. The size of the supply-

side bonding jumper in each raceway or overhead shall be

based on the total circular mil area of the parallel un-

grounded conductors in the raceway or overhead, as indi-

cated in 250.186(A)(1), but not smaller than 1/0 AWG.

(3) Impedance Grounded Neutral Systems. Impedance



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grounded neutral systems shall be installed in accordance

with 250.187.

250.194 Grounding and Bonding of Fences and Other

Metal Structures. Metallic fences enclosing, and other metal

structures in or surrounding, a substation with exposed electri-

cal conductors and equipment shall be grounded and bonded

to limit step, touch, and transfer voltages.

(A) Metal Fences. Where metal fences are located within

5 m (16 ft) of the exposed electrical conductors or equip-

ment, the fence shall be bonded to the grounding electrode

system with wire-type bonding jumpers as follows:

(1) Bonding jumpers shall be installed at each fence corner

and at maximum 50 m (160 ft) intervals along the

fence.

(2) Where bare overhead conductors cross the fence, bonding

jumpers shall be installed on each side of the crossing.

(3) Gates shall be bonded to the gate support post, and

each gate support post shall be bonded to the grounding

electrode system.

(4) Any gate or other opening in the fence shall be bonded

across the opening by a buried bonding jumper.

(5) The grounding grid or grounding electrode systems

shall be extended to cover the swing of all gates.

(6) The barbed wire strands above the fence shall be

bonded to the grounding electrode system.

Alternate designs performed under engineering supervi-

sion shall be permitted for grounding or bonding of metal

fences.

Informational Note No. 1: A nonconducting fence or section

may provide isolation for transfer of voltage to other areas.

Informational Note No. 2: See IEEE 80-2000, IEEE Guide for

Safety In AC Substation Grounding, for design and in-

stallation of fence grounding.

Change Description: This proposal is meant to establish basic prescriptive requirements for grounding and bonding of metal fences built in and around substations. For situations where step and touch potential considerations indicate additional grounding and bonding design is required, alternate designs performed under engineering supervision are allowed. Designers are also referred to the industry standard on the grounding of fences in and around substations, which is IEEE 80 Guide for Safety In AC Substation Grounding. Impact(s) : No negative impact – Typically IEEE 80 is followed in design of substation fence grounding.

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(B) Metal Structures. All exposed conductive metal struc-

tures, including guy wires within 2.5 m (8 ft) vertically or

5 m (16 ft) horizontally of exposed conductors or equip-

ment and subject to contact by persons, shall be bonded to

the grounding electrode systems in the area.

ARTICLE 285 Surge-Protective Devices (SPDs), 1000 Volts or less

285.13 Type 4 and Other Component Type SPDs. Type

4 component assemblies and other component type SPDs

shall only be installed by the equipment manufacturer.

Change Description: Type 4 and 5 SPDs are not standalone devices and are only acceptable if provided as a part of listed equipment. This new section makes it into a requirement. Impact(s) : No negative impact.

2

ARTICLE 300 General Requirements for Wiring Methods and Materials

300.22 Wiring in Ducts Not Used for Air Handling,

Fabricated Ducts for Environmental Air, and Other

Spaces for Environmental Air (Plenums).

(B) Ducts Specifically Fabricated for Environmental

Air. Equipment, devices, and devices the wiring methods

specified in this section shall be permitted within such

ducts only if necessary for the direct action upon, or sens-

ing of, the contained air. Where equipment or devices are

installed and illumination is necessary to facilitate mainte-

nance and repair, enclosed gasketed-type luminaires shall

be permitted.

Only wiring methods consisting of Type MI cable without

an overall nonmetallic covering, Type MC cable em-

ploying a smooth or corrugated impervious metal sheath

without an overall nonmetallic covering, electrical metallic

Change Description: Section updated to allow MI cable without an overall nonmetallic covering for use in Ducts Not Used for Air Handling, Fabricated Ducts for Environmental Air, and Other Spaces for Environmental Air (Plenums). This aligns this section with the wiring methods described in NFPA 90A. Impact(s) : No negative impact – Typically NFPA 90A requirements are followed in design.

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tubing, flexible metallic tubing, intermediate metal conduit,

or rigid metal conduit without an overall nonmetallic cov-

ering shall be installed in ducts specifically fabricated to

transport environmental air. Flexible metal conduit shall be

permitted, in lengths not to exceed 1.2 m (4 ft), to connect

physically adjustable equipment and devices permitted to

be in these fabricated ducts. The connectors used with flex-

ible metal conduit shall effectively close any openings in

the connection.

300.22 Wiring in Ducts Not Used for Air Handling,

Fabricated Ducts for Environmental Air, and Other

Spaces for Environmental Air (Plenums).

(C) Other Spaces Used for Environmental Air (Ple-

nums). This section shall apply to spaces not specifically

fabricated for environmental air-handling purposes but used

for air-handling purposes as a plenum. This section shall

not apply to habitable rooms or areas of buildings, the

prime purpose of which is not air handling.

(1) Wiring Methods. The wiring methods for such other

space shall be limited to totally enclosed, nonventilated,

insulated busway having no provisions for plug-in connec-

tions, Type MI cable without an overall nonmetallic cover-

ing, Type MC cable without an overall nonmetallic cover-

ing, Type AC cable, or other factory-assembled

multiconductor control or power cable that is specifically

listed for use within an air-handling space, or listed prefab-

ricated cable assemblies of metallic manufactured wiring

systems without nonmetallic sheath. Other types of cables,

conductors, and raceways shall be permitted to be installed

in electrical metallic tubing, flexible metallic tubing, inter-

mediate metal conduit, rigid metal conduit without an over-

all nonmetallic covering, flexible metal conduit, or, where

accessible, surface metal raceway or metal wireway with

metal covers.

Nonmetallic cable ties and other nonmetallic cable ac-

cessories used to secure and support cables shall be listed

as having low smoke and heat release properties.

Change Description: Section updated to allow MI cable without an overall nonmetallic covering for use in Ducts Not Used for Air Handling, Fabricated Ducts for Environmental Air, and Other Spaces for Environmental Air (Plenums). This aligns this section with the wiring methods described in NFPA 90A. In addition, this section now requires that cable ties and other cable accessories be listed as having low smoke and low heat generation characteristics. Impact(s) : No negative impact – Typically NFPA 90A requirements are followed in design.

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300.38 Raceways in Wet Locations Above Grade. Where

raceways are installed in wet locations above grade, the

interior of these raceways shall be considered to be a wet

location. Insulated conductors and cables installed in race-

ways in wet locations above grade shall comply with

310.10(C).

Change Description: This section applies to systems with voltages over 1000 V and addresses requirements for raceways in wet locations, above ground, aligning it with Section 300.9 for voltages below 1000 V. Impact(s) : No negative impact.

2

300.45 Warning Signs. Warning signs shall be conspicu-

ously posted at points of access to conductors in all conduit

systems and cable systems. The warning sign(s) shall be

legible and permanent and shall carry the following word-

ing:

DANGER—HIGH VOLTAGE—KEEP OUT

Change Description: Added new section to address warning signs at the points of access to conductors operating at voltages above 1000 V. This requirement already exists in articles 314 and 490 (previously in 225). Impact(s) : No negative impact.

2

300.50 Underground Installations.

(A) General. Underground conductors shall be identified

for the voltage and conditions under which they are in-

stalled. Direct-burial cables shall comply with the provi-

sions of 310.10(F). Underground cables shall be installed in

accordance with 300.50(A)(1) ,(A)(2), or (A)(23), and the

installation shall meet the depth requirements of Table

300.50.

(2) Industrial Establishments. In industrial establish-

ments, where conditions of maintenance and supervision

ensure that only qualified persons service the installed

cable, nonshielded single-conductor cables with insulation

types up to 2000 volts that are listed for direct burial shall

be permitted to be directly buried.

Change Description: It is a common practice in large utility-scale solar installations to direct bury 2000V rated conductors used to carry power from combiner boxes to the inverter. Since these installations are not accessible to the public and maintenance is controlled by the facility owner, direct buried single conductor installations are appropriate. There are already Listed PV wire products rated at 2000 volts and listed for direct burial, and placing this language in Article 300 ensures that the NEC is ready for other non- PV installations and similarly listed cable types that may be developed in the future. Having the language in 300.50 makes it easy for the code user to reference and apply the appropriate installation requirements, such as depth of burial and warning tape. Impact(s) :

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No negative impact.

ARTICLE 310 Conductors for General Wiring

310.15 Ampacities for Conductors Rated 0–2000 Volts.

(B) Tables.

(3) Adjustment Factors.

(c) Circular Raceways and Cables Exposed to Sunlight

on Rooftops. Where conductorsraceways or cables are in-

stalled in circular raceways exposed to direct sunlight on or

above rooftops, the adjustments shown in Table

310.15(B)(3)(c) shall be added to the outdoor temperature

to determine the applicable ambient temperature for appli-

cation of the correction factors in Table 310.15(B)(2)(a) or

Table 310.15(B)(2)(b).

Exception: Type XHHW-2 insulated conductors shall not

be subject to this ampacity adjustment.

Change Description: Exception was added recognizing that cross-linked synthetic polymer insulation (XHHW-2) is not subject to the melting when exposed to higher temperatures expected on the roof tops. The failure temperature of this type of insulation is in temperatures over 300°C and installations using XHHW-2 type conductors show no signs of failure even when fully loaded and installed in the hottest regions of the country.


2

ARTICLE 314 Outlet, Device, Pull, and Junction Boxes; Conduit Bodies: Fittings, and Handholes

314.15 Damp or Wet Locations. In damp or wet loca-

tions, boxes, conduit bodies, outlet box hoods, and fittings

shall be placed or equipped so as to prevent moisture from

entering or accumulating within the box, conduit body, or

fitting. Boxes, conduit bodies, outlet box hoods, and

fittings installed in wet locations shall be listed for use in

wet locations. Approved drainage openings not larger than 6

mm (1⁄4 in.) shall be permitted to be installed in the field

in boxes or conduit bodies listed for use in damp or wet

locations. For installation of listed drain fittings, larger

openings are permitted to be installed in the field in

accordance with manufacturer’s instructions.

Change Description: The Code now recognizes a common practice of adding weep holes in the field to prevent accumulation of condensed moisture in boxes. This change will improve durability and safety of the installations. Impact(s) : No negative impact.

2

314.16 Number of Conductors in Outlet, Device, and

Junction Boxes, and Conduit Bodies. Change Description: This change adds a clarity regarding box fill calculation and

2



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(B) Box Fill Calculations.

(2) Clamp Fill. Where one or more internal cable clamps,

whether factory or field supplied, are present in the box, a

single volume allowance in accordance with Table

314.16(B) shall be made based on the largest conductor

present in the box. No allowance shall be required for a

cable connector with its clamping mechanism outside the

box.

A clamp assembly that incorporates a cable termination for

the cable conductors shall be listed and marked for use with

specific nonmetallic boxes. Conductors that originate within

the clamp assembly shall be included in conductor fill

calculations covered in 314.16(B)(1) as though they entered

from outside the box. The clamp assembly shall not require

a fill allowance, but the volume of the portion of the

assembly that remains within the box after installation shall

be excluded from the box volume as marked in

314.16(A)(2).

considering clamp assemblies in determining a box volume. Impact(s) : No negative impact.

314.25 Covers and Canopies. In completed installations,

each box shall have a cover, faceplate, lampholder, or lu-

minaire canopy, except where the installation complies with

410.24(B). Screws used for the purpose of attaching covers,

or other equipment, to the box shall be either machine

screws matching the thread gauge or size that is integral to

the box or shall be in accordance with the manufacturer’s

instruction.

Change Description: This change ensures that only screws appropriate for the box are used to attach covers and other equipment. This will prevent use of screws not matching the thread gauge or size and minimize chances for damaging the box in the process of attaching covers or other equipment to the boxes. Impact(s) : No negative impact.

2

314.28 Pull and Junction Boxes and Conduit Bodies.

(A) Minimum Size.

(3) Smaller Dimensions. Boxes Listed boxes or listed

Change Description: This change allows use of Table 1 (Chapter 9) in establishing number of conductors to be installed in listed conduit bodies meeting conditions described in this section.

2



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conduit bodies of dimensions less than those required in

314.28(A)(1) and (A)(2) shall be permitted for installations

of combinations of conductors that are less than the maxi-

mum conduit or tubing fill (of conduits or tubing being

used) permitted by Table 1 of Chapter 9, provided the box

or conduit body has been listed for, and is permanently

marked with, the maximum number and maximum size of

conductors permitted.

Listed conduit bodies of dimensions less than those re-

quired in 314.28(A)(2), and having a radius of the curve to

the centerline not less than that indicated in Table 2 of

Chapter 9 for one-shot and full-shoe benders, shall be per-

mitted for installations of combinations of conductors per-

mitted by Table 1 of Chapter 9. These conduit bodies shall

be marked to show they have been specifically evaluated in

accordance with this provision.

Where the permitted combinations of conductors for

which the box or conduit body has been listed are less than

the maximum conduit or tubing fill permitted by Table 1 of

Chapter 9, the box or conduit body shall be permanently

marked with the maximum number and maximum size of

conductors permitted.


ARTICLE 330 Metal-Clad Cable: Type MC

330.10 Uses Permitted.

(A) General Uses. Type MC cable shall be permitted as

follows:

(11) In wet locations where a corrosion-resistant jacket is

provided over the metallic covering and any of the

following conditions are met:

a. The metallic covering is impervious to moisture.

b. A moisture-impervious jacket resistant to moisture

is provided under the metal covering.

c. The insulated conductors under the metallic covering

are listed for use in wet locations, and a corrosion-

Change Description: The revised wording is consistent with the requirements for jackets in UL 1569, which contains the performance requirements that define resistance to moisture.


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resistant jacket is provided over the metallic

sheath.locations.

330.30 Securing and Supporting.

(B) Securing. Unless otherwise provided, cables shall be

secured at intervals not exceeding 1.8 m (6 ft). Cables con-

taining four or fewer conductors sized no larger than 10

AWG shall be secured within 300 mm (12 in.) of every

box, cabinet, fitting, or other cable termination. In vertical

installations, listed cables with ungrounded conductors 250

kcmil and larger shall be permitted to be secured at inter-

vals not exceeding 3 m (10 ft)

Change Description: Increased support spacing requirements for MC cables with conductors 250 kcmil and larger in vertical installations based on UL Report 12ME07391 demonstrating acceptability of this change. Impact(s) : No negative impact.

2


(D) Unsupported Cables. Type MC cable shall be permit-

ted to be unsupported where the cable:

(3) Is Type MC of the interlocked armor type in lengths

not exceeding 900 mm (3 ft) from the last point where it is

securely fastened and is used to connect equipment where

flexibility is necessary to minimize the transmission of

vibration from equipment or to provide flexibility for

equipment that requires movement after installation.

Change Description: This change allows the use of a MC cable of the interlocked armor type in applications requiring flexibility at terminations with the last support 3 ft or less from the termination point. Impact(s) : No negative impact.

2

ARTICLE 334 Nonmetallic-Sheathed Cable: Types NM, NMC, and NMS

334.40 Boxes and Fittings.

(B) Devices of Insulating Material. Switch,Self-

contained switches,outlet, self-contained receptacles, and

tap nonmetallic-sheathed cable interconnector devices of

insulating material that are listed shall be permitted to be

used without boxes in exposed cable wiring and for rewir-

ingrepair wiring in existing buildings where the cable is

concealed and fished.concealed. Openings in such devices

shall form a close fit around the outer covering of the cable,

and the device shall fully enclose the part of the cable from

which any part of the covering has been removed. Where

Change Description: Clarified the language in this section by changing term “rewiring” (typically associated with pulling new wires) to “repair”. This change also makes it acceptable to install listed self-contained devices without boxes in exposed or concealed wiring in existing buildings. Impact(s) : No negative impact.

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connections to conductors are by binding-screw terminals,

there shall be available as many terminals as conductors.

ARTICLE 338 Service-Entrance Cable: Types SE and USE

338.10 Uses Permitted.

(B) Branch Circuits or Feeders.

(4) Installation Methods for Branch Circuits and Feed-

ers.

(b) Exterior Installations. In addition to the provisions of

this article, service-entrance cable used for feeders or branch

circuits, where installed as exterior wiring, shall be installed

in accordance with Part I of Article 225. The cable shall be

supported in accordance with 334.30. Type USE cable

installed as underground feeder and branch circuit cable shall

comply with Part II of Article 340.

Exception: Single-conductor Type USE and multi-rated

USE conductors shall not be subject to the ampacity limi-

tations of Part II of Article 340.

Change Description: This new exception removes the requirement to apply 60°C ampacity rating limitation per 340.80 to USE type cables, which have higher than 60°C temperature rating. Impact(s) : No negative impact.

2

ARTICLE 348 Flexible Metal Conduit: Type FMC


(A) Securely Fastened.

Exception No. 4: Lengths not exceeding 1.8 m (6 ft) from

the last point where the raceway is securely fastened for

connections within an accessible ceiling to a luminaire(s)

or other equipment. For the purposes of this exception,

listed flexible metal conduit fittings shall be permitted as a

means of support.

Change Description: This change allows considering listed flexible metal conduit fittings as means of support for the purpose of complying with the code, similar to the provisions for AC and MC type cables (320.30 and 330.30, respectively). Impact(s) : No negative impact.

2

ARTICLE 350



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Liquidtight Flexible Metal Conduit: Type LFMC 350.30 Securing and Supporting.

(A) Securely Fastened.

Exception No. 4: Lengths not exceeding 1.8 m (6 ft) from

the last point where the raceway is securely fastened for

connections within an accessible ceiling to a luminaire(s)

or other equipment. For the purposes of this exception,

listed LFMC fittings shall be permitted as a means of

support.

Change Description: Companion change to 348.30 - this change allows considering listed liquidtight flexible metal conduit fittings as means of support for the purpose of complying with the code, similar to the provisions for AC and MC type cables (320.30 and 330.30, respectively). Impact(s) : No negative impact.

2

350.42 Couplings and Connectors. Only fittings listed for

use with LFMC shall be used. Angle connectors shall not

be concealed. Straight LFMC fittings shall be permitted for

direct burial where marked.

Change Description: This change identifies limitations for LFMC fittings. It also harmonizes these provisions with the same provisions for LFNC in Section 356.42. Impact(s) : No negative impact.

2

ARTICLE 356 Liquidtight Flexible Nonmetallic Conduit: Type LFNC

356.12 Uses Not Permitted. LFNC shall not be used as

follows:

(4) Where the operating voltage of the contained conduc-

tors is in excess of 600 volts, nominal, except as permitted

in 600.32(A).

Change Description: This change removes the application limitation for LFNC to below 600 V installations. This change is based on the listing for LFNC (UL 1660 and UL White Book, DXOQ) which do not limit LFNC to 600 V. Impact(s) : No negative impact.

2

356.30 Securing and Supporting. Type LFNC-B shall

be securely fastened and supported in accordance with

one of the following:

4) Securing or supporting of LFNC-B shall not be re-

quired where installed in lengths not exceeding 1.8 m (6

Change Description: Companion change to 348.30 - this change allows considering listed liquidtight flexible nonmetallic conduit fittings as means of support for the purpose of complying with the code, similar to the provisions for AC and MC type cables (320.30 and 330.30,

2



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ft) from the last point where the raceway is securely

fastened for connections within an accessible ceiling to a

luminaire(s) or other equipment. For the purpose of

356.30, listed liquidtight flexible nonmetallic conduit

fittings shall be permitted as a means of support.

respectively). Impact(s) : No negative impact.

356.60 Grounding and Bonding.Grounding. Where used

to connect equipment where flexibility grounding is re-

quired, an a separate equipment grounding conductor shall

be installed in the conduit.

Where required or installed, equipment grounding con-

ductors shall be installed in accordance with 250.134(B).

Where required or installed, equipment bonding jumpers

shall be installed in accordance with 250.102.

Exception No. 1: As permitted in 250.134(B), Exception

No. 2, for dc circuits and 250.134(B), Exception No. 1, for

separately run equipment grounding conductors.

Exception No. 2: Where the grounded conductor is used to

ground equipment as permitted in 250.142.

Change Description: This change provides more clarity and harmonizes equipment grounding requirements applicable to LFNC with requirements for other nonmetallic raceways. Impact(s) : No negative impact.

2

ARTICLE 370 Cablebus

The text of this reorganized article not

included for brevity.

Change Description: Article 370 was reorganized in its entirety to more closely follow Chapter 3 numbering system. Impact(s) : No negative impact.

1

ARTICLE 376 Metal Wireways

376.56 Splices, Taps, and Power Distribution Blocks.

(B) Power Distribution Blocks.

(1) Installation. Power distribution blocks installed in

metal wireways shall be listed. Power distribution blocks

Change Description: Added language clarifies the expectation that the power distribution blocks installed on the line side of the service equipment shall be listed for that purpose. In (5) the added text

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installed on the line side of the service equipment shall be

listed for the purpose.

(5) Conductors. Conductors shall be arranged so the

power distribution block terminals are unobstructed follow-

ing installation.

ensures that the conductors do not obstruct block terminals – this requirement is consistent with 314.28(E) applicable to boxes. Impact(s) : No negative impact.

ARTICLE 386 Surface Metal Raceways

386.120 Marking. Each length of surface metal raceway

shall be clearly and durably identified as required in the

first sentence of 110.21(A).

Change Description: This addition of the clause covering marking to bring consistency with the requirements in other articles for similar products. Impact(s) : No negative impact.

2

ARTICLE 388 Surface Nonmetallic Raceways

388.120 Marking. Surface nonmetallic raceways that have

limited smoke-producing characteristics shall be permitted to

be so identified. Each length of surface nonmetallic raceway

shall be clearly and durably identified as required in the

first sentence of 110.21(A).

Change Description: This addition of the clause covering marking to bring consistency with the requirements in other articles for similar products. Impact(s) : No negative impact.

2

ARTICLE 392 Cable Trays

392.18 Cable Tray Installation.

(H) Marking. Cable trays containing conductors rated

over 600 volts shall have a permanent, legible warning

notice carrying the wording “DANGER — HIGH VOLT-

AGE — KEEP AWAY” placed in a readily visible position

on all cable trays, with the spacing of warning notices not

to exceed 3 m (10 ft). The danger marking(s) or labels shall

Change Description: The added exception for industrial applications eliminates the requirement for marking cable trays containing conductors rated over 600V, if the cable tray is not accessible. Impact(s) : Improves safety - no negative impact.

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comply with 110.21(B).

Exception: Where not accessible (as applied to equip-

ment), in industrial establishments where the conditions of

maintenance and supervision ensure that only qualified

persons service the installation, cable tray system warning

notices shall be located where necessary for the installation

to ensure safe maintenance and operation.

392.20 Cable and Conductor Installation.

(A) Multiconductor Cables RatedOperating at

600Volts or Less. Multiconductor cables rated operating at

600 volts or less shall be permitted to be installed in the

same cable tray.

(B) Cables RatedOperating at Over 600 Volts. Cables

rated operating at over 600 volts and those ratedoperating

at 600 volts or less installed in the same cable tray shall

comply with either of the following:

(1) The cables ratedoperating at over 600 volts are Type

MC.

(2) The cables rated operating at over 600 volts are sepa-

rated from the cables ratedoperating at 600 volts or less

by a solid fixed barrier of a material compatible with

the cable tray.

Change Description: Replaced term “rated” with “operating at” within the subsection to allow selection of conductor insulation level based on maximum circuit voltage applied to any conductor within the enclosure or raceway, rather than the insulation rating itself. Impact(s) : No negative impact.

2

ARTICLE 393 Low-Voltage Suspended Ceiling Power Distribution Systems

The text of this new article not included for brevity.

Change Description: Added a new Article covering the installation of low-voltage Class 2 ac and dc suspended ceiling power distribution systems. Impact(s) : No negative impact – improves safety by providing specific requirements for the systems until now not addressed by the code.

2

ARTICLE 400



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Flexible Cords and Cables 400.4 Types. Flexible cords and flexible cables shall con-

form to the description in Table 400.4. Types 400.4. The

use of flexible cords and flexible cables other than those

listed in the tableTable 400.4 shall be the subject of special

investigation.require permission by the authority having ju-

risdiction.

Change Description: This change requires that flexible cords not listed in Table 400.4 be approved by AHJ prior to application. Impact(s) : Any NEC unlisted flexible cords will require evaluation.

2

400.5 Ampacities for Flexible Cords and Cables.

(A) Ampacity Tables. Table 400.5(A)(1) provides the al-

lowable ampacities, and Table 400.5(A)(2) provides the

ampacities for flexible cords and cables with not more than

three current-carrying conductors. These tables shall be

used in conjunction with applicable end-use product stan-

dards to ensure selection of the proper size and type. Where

cords and cables are used in ambient temperatures other

than 30°C (86°F), the temperature correction factors from

Table 310.15(B)(2)(a) that correspond to the temperature

rating of the cord or cable shall be applied to the ampacity in

Table 400.5(A)(1) and Table 400.5(A)(2). Cords and

cables rated 105°C shall use correction factors in the 90°C

column of Table 310.15(B)(2)(a) for temperature correction.

Where the number of current-carrying conductors exceeds

three, the allowable ampacity or the ampacity of each

conductor shall be reduced from the 3three-conductor rat-

ing as shown in Table 400.5(A)(3).

Change Description: This change corrects an omission in the 2011 edition of the code which did not require application of temperature correction factors to cables listed in Table 400.5(A)(1). Impact(s) : No negative impact.

2

400.6 Markings.

(A) Standard Markings. Flexible cords and cables shall be

marked by means of a printed tag attached to the coil reel or

carton. The tag shall contain the information required in

310.120(A). Types S, SC, SCE, SCT, SE, SEO, SEOO, SJ,

SJE, SJEO, SJEOO, SJO, SJT, SJTO, SJTOO, SO, SOO, ST,

STO, STOO, SEW, SEOW, SEOOW, SJEW, SJEOW,

SJEOOW, SJOW, SJTW, SJTOW, SJTOOW, SOW,

SOOW, STW, STOW, and STOOW flexible cords and G, G-

Change Description: Expanded marking requirements for flexible cords and cables to include maximum operating temperature. Impact(s) : No negative impact.

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GC, PPE, and W flexible cables shall be durably marked on

the surface at intervals not exceeding 610 mm (24 in.) with the

type designation, size, and number of conductors. Required

markings on tags, cords, and cables shall also include the

maximum operating temperature of the flexible cord or cable.

400.7 Uses Permitted. (A) Uses. Flexible cords and cables shall be used only for

the following:

(11) Between an existing receptacle outlet and an inlet,

where the inlet provides power to an additional single

receptacle outlet. The wiring interconnecting the inlet

to the single receptacle outlet shall be a Chapter 3 wiring

method. The inlet, receptacle outlet, and Chapter 3 wiring

method, including the flexible cord and fittings, shall be a

listed assembly specific for this application.

Change Description: This new provision expands the use of flexible cords and cables to allow new listed products primarily used for flat-screen TV mounted on the wall. Impact(s) : No negative impact.

2

400.23 Equipment Grounding Conductor Identifica-

tion. A conductor intended to be used as an equipment

grounding conductor shall have a continuous identifying

marker readily distinguishing it from the other conductor or

conductors. Conductors having a continuous green color or

a continuous green color with one or more yellow stripes

shall not be used for other than equipment grounding con-

ductors. Cords or cables consisting of integral insulation

and a jacket without a nonintegral grounding conductor

shall be permitted to be green. The identifying marker shall

consist of one of the methods in 400.23(A) or (B).

Change Description: This change allows the use of green color for cords or cables with integral insulation and jacket and without a nonintegral grounding conductor. Impact(s) : No negative impact.

2

III. Portable Cables Over 600 Volts, Nominal

400.31 Construction.

(B) Equipment Grounding Conductor(s). An equipment

grounding conductor(s) shall be provided in cables with

three or more conductors. The total area shall not be less

than that of the size of the equipment grounding conductor

required in 250.122.

Change Description: Clarifies that two conductor cables are acceptable without a grounding conductor. Impact(s) : No negative impact.

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ARTICLE 404 Switches

404.2 Switch Connections.

(C) Switches Controlling Lighting Loads. Where

switches control lighting loads supplied by a general pur-

pose branch circuit, the The grounded circuit conductor for

the controlled lighting circuit shall be provided at the

switch location.location where switches control lighting

loads that are supplied by a grounded general-purpose

branch circuit for other than the following:

Exception: The grounded circuit conductor shall be per-

mitted to be omitted from the switch enclosure where either

of the following conditions in (1) or (2) apply:

(1) Conductors for switches controlling lighting loads en-

ter the box through a raceway. The raceway shall have

suffıcient cross-sectional area to accommodate the ex-

tension of the grounded circuit conductor of the light-

ing circuit to the switch location whether or not the

conductors in the raceway are required to be increased

in size to comply with 310.15(B)(3)(a). Where conduc-

tors enter the box enclosing the switch through a race-

way, provided that the raceway is large enough for all

contained conductors, including a grounded conductor.

(2) Cable assemblies for switches controlling lighting

loads enter the box through a framing cavity that is

open at the top or bottom on the same floor level, or

through a wall, floor, or ceiling that is unfinished on

one side.Where the box enclosing the switch is acces-

sible for the installation of an additional or replacement

cable without removing finish materials

(3) Where snap switches with integral enclosures comply

with 300.15(E)

(4) Where a switch does not serve a habitable room or

Change Description: This change rearranges the Section for clarity and adds five new conditions for which a grounded conductor does not have to be provided at the lighting switch location to accommodate common situation where bringing the grounded conductor would not improve safety or serve other purposes. Impact(s) : No negative impact.

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bathroom

(5) Where multiple switch locations control the same light-

ing load such that the entire floor area of the room or

space is visible from the single or combined switch

locations

(6) Where lighting in the area is controlled by automatic

means

(7) Where a switch controls a receptacle load

404.8 Accessibility and Grouping.

(C) Multipole Snap Switches. A multipole, general-use

snap switch shall not be permitted to be fed from more than

a single circuit unless it is listed and marked as a two-

circuit or three-circuit switch, or unless its voltage rating is

not less than the nominal line-to-line voltage of the system

supplying the circuits.switch.

Change Description: The language added in 2008 NEC allowing use of snap switches on more than a single branch circuit is removed from this edition of the code for switches not specifically listed for such an application. Impact(s) : No negative impact.

2

404.10 Mounting of Snap Switches.

(B) Box Mounted. Flush-type snap switches mounted in

boxes that are set back of the finished surface as permitted

in 314.20 shall be installed so that the extension plaster ears

are seated against the surface. Flush-type snap switches

mounted in boxes that are flush with the finished surface or

project from it shall be installed so that the mounting yoke

or strap of the switch is seated against the box. Screws used

for the purpose of attaching a snap switch to a box shall be

of the type provided with a listed snap switch, or shall be

machine screws having 32 threads per inch or part of listed

assemblies or systems, in accordance with the manufactur-

er’s instructions.

Change Description: This change provides specific requirements for screws used in mounting snap switches to ensure that inappropriate screws which could potentially damage the switch are not being utilized. Impact(s) : No negative impact.

2

ARTICLE 406 Receptacles, Cord Connectors, and Attachment Plugs (Caps)

406.3 Receptacle Rating and Type.

Change Description: This change introduces a requirement for marking automatically

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(E) Controlled Receptacle Marking. All nonlocking-

type, 125-volt, 15- and 20-ampere receptacles that are con-

trolled by an automatic control device, or that incorporate

control features that remove power from the outlet for the

purpose of energy management or building automation,

shall be marked with the symbol shown in Figure 406.3(E)

and located on the controlled receptacle outlet where vis-

ible after installation.

Exception: The marking is not required for receptacles

controlled by a wall switch that provide the required room

lighting outlets as permitted by 210.70.

controlled receptacles. Impact(s) : No negative impact.

406.4 General Installation Requirements.

(A) Grounding Type. Except as provided in 406.4(D),

Rreceptacles installed on 15- and 20-ampere branch circuits

shall be of the grounding type. Grounding-type receptacles

shall be installed only on circuits of the voltage class and

current for which they are rated, except as provided in

Table 210.21(B)(2) and Table 210.21(B)(3).

Exception: Nongrounding-type receptacles installed in ac-

cordance with 406.4(D).

D) Replacements. Replacement of receptacles shall com-

ply with 406.4(D)(1) through (D)(6), as applicable. Arc-

fault circuit-interrupter type and ground-fault circuit-

interrupter type receptacles shall be installed in a readily

accessible location.

(3) Ground-Fault Circuit Interrupters. Ground-fault

circuit-interrupter protected receptacles shall be provided

where replacements are made at receptacle outlets that are

required to be so protected elsewhere in this Code.

Exception: Where replacement of the receptacle type is

impracticable, such as where the outlet box size will not

permit the installation of the GFCI receptacle, the recep-

Change Description: This requirement expands the accessibility of receptacles requiring testing (GFCI, AFCI) to replacement receptacles. Also, a new exception allows replacement of a receptacle which would otherwise be required to be of a GFCI type with the existing type (not GFCI) if the receptacle is protected by an upstream GFCI device. Impact(s) : No negative impact.

2



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tacle shall be permitted to be replaced with a new recep-

tacle of the existing type, where GFCI protection is pro-

vided and the receptacle is marked “GFCI protected” and

“no equipment ground,” in accordance with 406.4(D)(2)

(a), (b), or (c).

406.5 Receptacle Mounting. Receptacles shall be

mounted in identified boxes or assemblies designed for the

purpose, and suchassemblies. The boxes or assemblies shall

be securely fastened in place unless otherwise permitted

elsewhere in this Code. Screws used for the purpose of

attaching receptacles to a box shall be of the type provided

with a listed receptacle, or shall be machine screws having

32 threads per inch or part of listed assemblies or systems,

in accordance with the manufacturer’s instructions.

Change Description: This change provides specific requirements for screws used in mounting receptacles to ensure that inappropriate screws which could potentially damage the receptacle are not being utilized. Impact(s) : No negative impact.

406.5 Receptacle Mounting.

(E) Receptacles in Countertops and Similar Work Sur-

faces in Dwelling Units.Surfaces. Receptacles, unless

listed as receptacle assemblies for countertop applications,

shall not be installed in a face-up position in countertops or

similar work surfaces. Where receptacle assemblies for

countertop applications are required to provide ground-fault

circuit-interrupter protection for personnel in accordance

with 210.8, such assemblies shall be permitted to be listed

as GFCI receptacle assemblies for countertop applications.

(F) Receptacles in Seating Areas and Other Similar

Surfaces. In seating areas or similar surfaces, receptacles

shall not be installed in a face-up position unless the recep-

tacle is any of the following:

(1) Part of an assembly listed as a furniture power

distribution unit, if cord-and plug-connected

2) Part of an assembly listed either as household

furnishings or as commercial furnishings

(3) Listed either as a receptacle assembly for countertop

applications or as a GFCI receptacle assembly for

Change Description: This change expands requirements for receptacles mounted in countertops (face-up) to all occupancies and provides criteria for GFCI protection. It also adds specific criteria for receptacles in seating areas in a face-up position. Impact(s) : No negative impact.

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countertop applications

(4) Installed in a listed floor box

406.9 Receptacles in Damp or Wet Locations.

(B) Wet Locations.

(1) Receptacles of 15 and 20-Amperes Receptacles in a

Wet Location. 15- and 20-ampere, 125- Receptacles of 15

and 250-volt receptacles20 amperes, 125 and 250 volts

installed in a wet location shall have an enclosure that is

weatherproof whether or not the attachment plug cap is

inserted. For other than one- or two-family dwellings, an

An outlet box hood installed for this purpose shall be

listed and where installed on an enclosure supported from

grade as described in 314.23(B) or as described in

314.23(F) shall be identified as “extra duty.” All 15-

and 20-ampere, 125- and 250-volt nonlocking-type

receptacles shall be listed weather- resistant type.

Change Description: Revision to this section expands requirements for an “extra duty” outlet box hood in wet locations, regardless of occupancy and enclosure mounting method. Impact(s) : No negative impact.

2

406.15 Dimmer-Controlled Receptacles. A receptacle

supplying lighting loads shall not be connected to a dimmer

unless the plug/receptacle combination is a nonstandard

configuration type that is specifically listed and identified

for each such unique combination.

Change Description: New section added restricting regarding dimmer control of receptacles. Impact(s) : No negative impact.

2

ARTICLE 408 Switchboards, Switchgear, and Panelboards

408.3 Support and Arrangement of Busbars and Con-

ductors.

(E) Bus Arrangement.

(2) DC Bus Arrangement. Direct-current ungrounded buses

shall be permitted to be in any order. Arrangement of dc buses

shall be field marked as to polarity, grounding system, and

Change Description: This new subsection provides criteria for DC bus arrangement. Impact(s) : No negative impact.

2



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nominal voltage.

408.3 Support and Arrangement of Busbars and Con-

ductors.

(F) Switchboard, Switchgear, or Panelboard Identifica-

tion.

(3) High-Impedance Grounded Neutral AC System. A

switchboard, switchgear, or panelboard containing a high-

impedance grounded neutral ac system in accordance with

250.36 shall be legibly and permanently field marked as

follows:

CAUTION: HIGH-IMPEDANCE GROUNDED NEU-

TRAL AC SYSTEM OPERATING — VOLTS BE-

TWEEN CONDUCTORS AND MAY OPERATE --- VOLTS TO GROUND FOR INDEFINITE PERIODS UN-

DER FAULT CONDITIONS

(4) Ungrounded DC Systems. A switchboard, switchgear,

or panelboard containing an ungrounded dc electrical

system in accordance with 250.169 shall be legibly and

permanently field marked as follows:

CAUTION: UNGROUNDED DC SYSTEM OPERAT-

ING — VOLTS BETWEEN CONDUCTORS

(5)) Resistively Grounded DC Systems. A

switchboard, switchgear, or panelboard containing a

resistive connection between current-carrying

conductors and the grounding system to stabilize

voltage to ground shall be legibly and permanently

field marked as follows:

CAUTION: DC SYSTEM OPERATING ---

VOLTS BETWEEN CONDUCTORS AND

MAY OPERATE — VOLTS TO GROUND FOR

INDEFINITE PERIODS UNDER FAULT CONDITIONS

Change Description: This new subsection requires permanent marking of electrical distribution equipment fed from a high-impedance grounded, ungrounded DC, and resistively grounded DC systems. Impact(s) : No negative impact.

2



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408.55 Wire-Bending Space Within an Enclosure Con-

taining a Panelboard.

(A) Top and Bottom Wire-Bending Space. The enclosure

for a panelboard shall have the top and bottom wire-

bending space sized in accordance with Table 312.6(B) for

the largest conductor entering or leaving the enclosure.

Side wire-bending space shall be in accordance with Table

312.6(A) for the largest conductor to be terminated in that

space.

(B) Side Wire-Bending Space. Side wire-bending space

shall be in accordance with Table 312.6(A) for the largest

conductor to be terminated in that space.

(C) Back Wire-Bending Space. Where a raceway or cable

entry is in the wall of the enclosure opposite a removable

cover, the distance from that wall to the cover shall be

permitted to comply with the distance required for one wire

per terminal in Table 312.6(A). The distance between the

center of the rear entry and the nearest termination for the

entering conductors shall not be less than the distance given

in Table 312.6(B).

Change Description: The revision expands the wire bending criteria to include back wire-bending space. Impact(s) : No negative impact.

2

ARTICLE 410 Luminaires, Lampholders, and Lamps

410.10 Luminaires in Specific Locations.

(F) Luminaires Installed in or Under Roof Decking. Lu-

minaires installed in exposed or concealed locations under

metal-corrugated sheet roof decking shall be installed and

supported so there is not less than 38 mm (11⁄2 in.) mea-

sured from the lowest surface of the roof decking to the top

of the luminaire.

Change Description: This new subsection provides specific requirements for a distance of luminaires from a metal corrugated roof decking. It minimizes a chance for damage of electrical components by roof material fasteners. Impact(s) : No negative impact.

2

410.23 Covering of Combustible Material at Outlet

Boxes. Any combustible wall or ceiling finish exposed be- Change Description: 2



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tween the edge of a luminaire canopy or pan and an outlet

box having a surface area of 1160 mm2 (180 in.2) or more

shall be covered with noncombustible material.

This revision aligns Section 410.23 with UL 1598, ensuring that larger boxes (not covered by UL 1598) do not overheat adjacent combustible wall and ceiling materials. Impact(s) : No negative impact.

XII. Special Provisions for Electric-Discharge Lighting

Systems of 1000 Volts or Less

410.130 General.

(G) Disconnecting Means.

(1) General. In indoor locations other than dwellings and

associated accessory structures, fluorescent luminaires that

utilize double-ended lamps and contain ballast(s) that can

be serviced in place shall have a disconnecting means ei-

ther internal or external to each luminaire. For existing

installed luminaires without disconnecting means, at the

time a ballast is replaced, a disconnecting means shall be

installed. The line side terminals of the disconnecting

means shall be guarded.

Exception No. 4: A disconnecting means shall not be re-

quired in industrial establishments with restricted public

access where conditions of maintenance and supervision

ensure that only qualified persons service the installation

by written procedures.

Change Description: This revision eliminates an exception for installation of disconnect switches for electric-discharge lighting over 1000 V in industrial establishments. Impact(s) : Elimination of this exception improves safety of personnel performing maintenance/repair work on electric-discharge lighting over 1000 V in industrial establishments.

2

ARTICLE 411 Lighting Systems Operating at 30 Volts or Less and Lighting Equipment Connected to Class 2 Power Sources

411.1 Scope. This article covers lighting systems operating

at 30 volts or less and their associated components. This

article also covers lighting equipment connected to a Class

Change Description: This revision provides clarification that the scope of the section

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2 power source includes lighting equipment connected to a Class 2 power source. Impact(s) : No negative impact.

411.2411.3 Definition.Low-Voltage Lighting Systems.

(A) General. Lighting Ssystems Ooperating at 30 Volts-

volts or Less. A lighting system consisting less shall consist

of an isolating power supply, the low-voltage luminaires,

and associated equipment that are all identified for the use.

The output circuits of the power supply are shall be rated

for not more than 25 amperes and operate at 30 volts (42.4

volts peak) or lessmaximum under all load conditions.

(B) Class 2. Listed Class 2 lighting equipment shall be

rated in conformance with Chapter 9, Table 11(A) or Table

11(B).

411.3411.4 Listing Required. Lighting systems operating

at 30 volts or less shall comply with 411.3(A)411.4(A) or

411.3(B).411.4(B). Class 2 power sources and lighting

equipment connected to Class 2 power sources shall be

listed.

Change Description: This revision better correlates this section with Article 725 and Chapter 9 Tables for Class 2 listed lighting systems. Impact(s) : No negative impact.

2

ARTICLE 422 Appliances

422.5 Ground-Fault Circuit-Interrupter (GFCI) Pro-

tection. The device providing GFCI protection required in

this article shall be readily accessible.

Change Description: This added section aligns requirements for accessibility of GFCI protection device with Section 210.8. Impact(s) : No negative impact.

2

422.11 Overcurrent Protection. Appliances shall be pro-

tected against overcurrent in accordance with 422.11(A)

through (G) and 422.10.

(F) Electric Heating Appliances Employing Resistance-

Change Description: Rearranged this section for better clarity and added low-pressure water heater tanks and open outlet water heater vessels to the scope.

2



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Type Heating Elements Rated More Than 48 Amperes.

(3) Water Heaters and Steam Boilers. Water heaters and

steam boilers employing resistance-type Resistance-type

immersion electric heating elements contained in an

ASME-rated and stamped vessel or listed instantaneous

water heaters shall be permitted to be subdivided into cir-

cuits not exceeding 120 amperes and protected at not more

than 150 amperes. as follows:

(1) Where contained in ASME-rated and stamped vessels

(2) Where included in listed instantaneous water heaters

(3) Where installed in low-pressure water heater tanks or

open-outlet water heater vessels


422.19 Space for Conductors. Canopies of ceiling-

suspended (paddle) fans and outlet boxes taken together

shall provide sufficient space so that conductors and their

connecting devices are capable of being installed in accor-

dance with 314.16. 422.20 Outlet Boxes to Be Covered. In a completed in-

stallation, each outlet box shall be provided with a cover

unless covered by means of a ceiling-suspended (paddle)

fan canopy. 422.21 Covering of Combustible Material at Outlet

Boxes. Any combustible ceiling finish exposed between the

edge of a ceiling-suspended (paddle) fan canopy or pan and

an outlet box shall be covered with noncombustible mate-

rial.

Change Description: Added three new sections addressing criteria for ceiling fan outlet boxes and their installation. Impact(s) : No negative impact.

2

422.23 Tire Inflation and Automotive Vacuum Ma-

chines. Tire inflation machines and automotive vacuum

machines provided for public use shall be protected by a

ground-fault circuit interrupter.

Change Description: Added a requirement for GFCI protection for tire inflation and automotive vacuum machines provided for public use. Impact(s) : No negative impact.

2



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422.31 Disconnection of Permanently Connected Appli-

ances.

C) Motor-Operated Appliances Rated over 1⁄8 Horse-

power. For permanently connected motor-operated appli-

ances with motors rated over 1⁄8 horse power, the branch-

circuit switch or circuit breaker shall be permitted to serve

as the disconnecting means where the switch or circuit

breaker is within sight from the appliance. The disconnect-

ing means shall comply with 430.109 and 430.110. For

permanently connected motor-operated appliances with

motors rated over 1⁄8 hp, the disconnecting means shall

meet 422.31(C)(1) or (2).

(1) The branch-circuit switch or circuit breaker shall be

permitted to serve as the disconnecting means where the

switch or circuit breaker is within sight from the appliance.

(2) The disconnecting means shall be installed within sight

of the appliance.

Change Description: Section rearranged for clarity. Impact(s) : No negative impact.

1

422.51 Cord-and-Plug-Connected Vending Machines.

B) Other Than Cord-and Plug-Connected. Vending ma-

chines not utilizing a cord and plug connection shall be con-

nected to a ground-fault circuit-interrupter protected circuit.

Change Description: This new subsection expands GFCI protection to hard-wired vending machines. Impact(s) : No negative impact.

2

ARTICLE 424 Fixed Electric Space-Heating Equipment

424.66 Installation.

(A) General. Duct heaters shall be installed in accordance

with the manufacturer’s instructions in such a manner that

operation does not create a hazard to persons or property.

Furthermore, duct heaters shall be located with respect to

building construction and other equipment so as to permit

access to the heater. Sufficient clearance shall be main-

tained to permit replacement of controls and heating ele-

Change Description: The addition to this section provides specific criteria for electric space heaters that are mounted on duct systems. Impact(s) : No negative impact.

2



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ments and for adjusting and cleaning of controls and other

parts requiring such attention. See 110.26.

Working space about electrical enclosures for resistance

heating element–type duct heaters that are mounted on duct

systems and contain equipment that requires examination,

adjustment, servicing, or maintenance while energized shall

comply with 424.66(B).

(B) Limited Access. Where the enclosure is located in a

space above a ceiling, all of the following shall apply:

(1) The enclosure shall be accessible through a lay-in type

ceiling or an access panel(s).

(2) The width of the working space shall be the width of

the enclosure or a minimum of 762 mm (30 in.), which-

ever is greater.

(3) All doors or hinged panels shall open to at least 90

degrees.

(4) The space in front of the enclosure shall comply with

the depth requirements of Table 110.26(A)(1). A hori-

zontal ceiling T-bar shall be permitted in this space.

ARTICLE 430 Motors, Motor Circuits, and Controllers

430.52 Rating or Setting for Individual Motor Circuit.

(C) Rating or Setting.

(5) Power Electronic Devices. SuitableSemiconductor

fuses intended for the protection of electronic devices shall

be permitted in lieu of devices listed in Table 430.52 for

power electronic devices, associated electromechanical de-

vices (such as bypass contactors and isolation contactors),

and conductors in a solid-state motor controller system,

provided that the marking for replacement fuses is provided

adjacent to the fuses.

Change Description: Clarified language addressing fusing for protection of electronic devices and expanded protection coverage to include associated electromechanical devices and conductors. Impact(s) : No negative impact.

2

430.53 Several Motors or Loads on One Branch Circuit.

(D) Single Motor Taps. For group installations described

above, the conductors of any tap supplying a single motor

shall not be required to have an individual branch-circuit

short-circuit and ground-fault protective device, provided

Change Description: The revised language in (2) clarifies where the 25 ft measurement is intended to reference, and improves readability. The revised language in (3) clarifies that the 10ft tap rule applies

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they comply with one of the following:

(2) No conductor to the motor shall have an ampacity less

than one-third that of the branch-circuit conductors,

with a minimum in accordance with 430.22, the. The

conductors from the point of the tap to the motor over-

load device being shall be not more than 7.5 m (25 ft)

long and beingbe protected from physical damage by

being enclosed in an approved raceway or by use of

other approved means.

(3) Conductors from the branch-circuit short-circuit and

ground-fault protective device to a listed manual motor

controller additionally marked “Suitable for Tap Con-

ductor Protection in Group Installations,” or to a

branch-circuit protective device, shall be permitted to have

an ampacity not less than one-tenth the rating or setting of

the branch-circuit short-circuit and ground- fault

protective device. The conductors from the controller to

the motor shall have an ampacity in accordance with

430.22. The conductors from the branch-circuit short-

circuit and ground-fault protective device point of the tap to

the controller(s) shall (1) be suitably protected from

physical damage and enclosed either by an enclosed

controller or by a raceway and be not more than 3 m (10 ft)

long or (2) have an ampacity not less than that of the

branch-circuit conductors

to the tap conductors and is consistent with (2). Impact(s) : No negative impact.

430.130 Branch-Circuit Short-Circuit and Ground-

Fault Protection for Single Motor Circuits Containing

Power Conversion Equipment.

(A) Circuits Containing Power Conversion Equipment.

Circuits containing power conversion equipment shall be

protected by a branch-circuit short-circuit and ground-fault

protective device in accordance with the following:

(1) The rating and type of protection shall be determined by

430.52(C)(1), (C)(3), (C)(5), or (C)(6), using the full-load

current rating of the motor load as determined by 430.6.

(2) Where maximum branch-circuit short-circuit and

ground-fault protective ratings are stipulated for specific

Change Description: New sections 430.130 and 430.131 are proposed to deal with the special requirements of the adjustable speed drive controller overcurrent protection functions. Impact(s) : No negative impact.

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device types in the manufacturer’s instructions for the

power conversion equipment or are otherwise marked on

the equipment, they shall not be exceeded even if higher

values are permitted by 430.130(A)(1).

(3) A self-protected combination controller shall only be

permitted where specifically identified in the manufac-

turer’s instructions for the power conversion equipment or if

otherwise marked on the equipment.

(B) Bypass Circuit/Device. Branch-circuit short-circuit

and ground-fault protection shall also be provided for a

bypass circuit/device(s). Where a single branch-circuit

short-circuit and ground-fault protective device is provided

for circuits containing both power conversion equipment

and a bypass circuit, the branch-circuit protective device

type and its rating or setting shall be in accordance with

those determined for the power conversion equipment and

for the bypass circuit/device(s) equipment.

430.131 Several Motors or Loads on One Branch Cir-

cuit Including Power Conversion Equipment. For instal-

lations meeting all the requirements of 430.53 that include

one or more power converters, the branch-circuit short-

circuit and ground-fault protective fuses or inverse time

circuit breakers shall be of a type and rating or setting

permitted for use with the power conversion equipment

using the full-load current rating of the connected motor

load in accordance with 430.53. For the purposes of 430.53

and 430.131, power conversion equipment shall be consid-

ered to be a motor controller.

ARTICLE 445 Generators

445.11 Marking. Each generator shall be provided with a

nameplate giving the manufacturer’s name, the rated fre- Change Description: This revision expands the requirements for marking generators

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quency, power factor, the number of phases if of alternating

current, ac, the subtransient and transient impedances, the

rating in kilowatts or kilovolt-amperes, the normal volts

and amperes corresponding to the rating, the rated revolu-

tions per minute, insulation system class and the rated am-

bient temperature or rated temperature rise, and time rating.

rise.

Nameplates for all stationary generators and portable

generators rated more than 15 kW shall also give the power

factor, the subtransient and transient impedances, the insu-

lation system class, and the time rating.

Marking shall be provided by the manufacturer to indicate

whether or not the generator neutral is bonded to the

generator frame. Where the bonding of a generator is modi-

fied in the field, additional marking shall be required to

indicate whether the generator neutral is bonded to the gen-

erator frame.

rated above 15 kW to include additional information required for the supplemental power system designer and the end user. Some of the information to be provided on the nameplate is no longer required for generators rated 15kW and below. Impact(s) : No negative impact.

445.16 Bushings. Where wires passfield-installed wiring

passes through an opening in an enclosure, a conduit box, or

a barrier, a bushing shall be used to protect the conductors

from the edges of an opening having sharp edges. The

bushing shall have smooth, well-rounded surfaces where it

may be in contact with the conductors. If used where oils,

grease, or other contaminants may be present, the bushing

shall be made of a material not deleteriously affected.

Change Description: Revised for better clarity. Impact(s) : No negative impact.

1

445.17 Generator Terminal Housings. Generator termi-

nal housings shall comply with 430.12. Where a horse-

power rating is required to determine the required mini-

mum size of the generator terminal housing, the full-load

current of the generator shall be compared with comparable

motors in Table 430.247 through Table 430.250. The higher

horsepower rating of Table 430.247 and Table 430.250

shall be used whenever the generator selection is between

two ratings.

Exception: This section shall not apply to generators

rated over 600 volts.

Change Description: Table 430.12 only applies to generators rated less than 600 volts. The sizes shown are too small for 15 kV conductors. See Article 430 Part XI for over 600 volts. Impact(s) : No negative impact.

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445.18 Disconnecting Means Required for Generators.

Generators shall be equipped with a disconnect(s), lockable in

the open position by means of which the generator and all

protective devices and control apparatus are able to be

disconnected entirely from the circuits supplied by the gen-

erator except where both of the following conditions apply:

(1) The driving means for the generator can be readily shut

down.Portable generators are cord- and plug- connected,

or

(2) Both of the following conditions apply:

a. The driving means for the generator can be readily

shut down, is rendered incapable of restarting, and is

lockable in the OFF position in accordance with

110.25.

(2)b. The generator is not arranged to operate in parallel

with another generator or other source of voltage.

Change Description: This change is partially based on the requirements found in UL 2200 which mandates a means to stop the driving means, prevent restarting, and requires the means to be lockable in OFF position. Impact(s) : Improves safety – no negative impact.

2

445.19 Generators Supplying Multiple Loads. A single

generator supplying more than one load, or multiple gen-

erators operating in parallel, shall be permitted to supply

either of the following:

(1) A vertical switchboard with separate sections

(2) Individual enclosures with overcurrent protection

tapped from a single feeder for load separation and

distribution if a generator(s) is provided with overcurrent

protection meeting the requirements of 240.15(A).

Change Description: This section has been deleted recognizing because the Article covering generators should not place restrictions on, or otherwise address, what a generator can supply. Impact(s) : No negative impact.

1

445.20 Ground-Fault Circuit-Interrupter Protection for

Receptacles on 15-kW or Smaller Portable Generators.

All 125-volt, single-phase, 15- and 20-ampere receptacle

outlets that are a part of a 15-kW or smaller portable gen-

erator either shall have ground-fault circuit-interrupter pro-

tection for personnel integral to the generator or receptacle

or shall not be available for use when the 125/250-volt

locking-type receptacle is in use. If the generator was

manufactured or remanufactured prior to January 1,

2015, listed cord sets or devices incorporating listed

Change Description: This new section adds a requirement for GFCI protection for 15- and 20-ampere receptacles mounted on portable generators, rated 15 kW or less, used frequently in camping, construction, and loss of power situations). This addition provides better protection to personnel utilizing portable equipment fed from such a generator.

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ground-fault circuit-interrupter protection for personnel

identified for portable use shall be permitted. If the

generator does not have a 125/250-volt locking-type

receptacle, this requirement shall not apply.


ARTICLE 450 Transformers and Transformer Vaults (including Secondary Ties)

450.5 Grounding Autotransformers. Grounding au-

totransformers covered in this section are zigzag or

T-connected transformers connected to 3-phase, 3-wire un-

grounded systems for the purpose of creating a 3-phase,

4-wire distribution system or providing a neutral point for

grounding purposes. Such transformers shall have a con-

tinuous per-phase current rating and a continuous neutral

current rating. Zigzag-connected transformers shall not be

installed on the load side of any system grounding connec-

tion, including those made in accordance with 250.24(B),

250.30(A)(1), or 250.32(B), Exception No. 1.

Exception: An auto transformer with a wye configuration

on its line side and a zigzag configuration on its load side

that does not permit neutral or ground-fault current to re-

turn over the line connection shall be permitted on the load

side of a system grounding connection. This exception shall

not apply to a connection made from a high-resistance

grounded system applied in accordance with 250.36

Change Description: Added new exception which allows the use of a special grounding autotransformer which does not permit neutral or ground-fault current to return over the line connection to be installed on the load side of the system grounding connection. This change allows the use of a device which provides equally safe installation but is less expensive, smaller, and more energy efficient. Impact(s) : No negative impact.

2

450.10 Grounding.

(A) Dry-Type Transformer Enclosures. Where separate

equipment grounding conductors and supply-side bonding

jumpers are installed, a terminal bar for all grounding and

bonding conductor connections shall be secured inside the

transformer enclosure. The terminal bar shall be bonded to

the enclosure in accordance with 250.12 and shall not be

installed on or over any vented portion of the enclosure.

Exception: Where a dry-type transformer is equipped with

wire-type connections (leads), the grounding and bonding

connections shall be permitted to be connected together

using any of the methods in 250.8 and shall be bonded to

Change Description: This new subsection eliminates a common practice of connecting grounding and bonding conductors at or over the venting openings resulting in less effective connection. The requirement for a terminal bar eliminates inconsistencies in installation and provides more effective connection. Impact(s) : Improves safety – no negative impact.

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the enclosure if of metal.

(B) Other Metal Parts. Where grounded, exposed non–

current-carrying metal parts of transformer installations, in-

cluding fences, guards, and so forth, shall be grounded and

bonded under the conditions and in the manner specified

for electrical equipment and other exposed metal parts in

Parts V, VI, and VII of Article 250.

450.11 Marking.

(B) Source Marking. A transformer shall be permitted to

be supplied at the marked secondary voltage, provided that

the installation is in accordance with the manufacturer’s

instructions.

Change Description: This added subsection clarifies that connecting a transformer in reverse (i.e., supply connected to the secondary winding) is only allowed if in accordance with manufacturer’s instructions. Impact(s) : Improves safety – no negative impact.

2

ARTICLE 480 Storage Batteries

480.3 Battery and Cell Terminations.

(A) Dissimilar Metals. Where mating dissimilar metals,

antioxidant material suitable for the battery connection

shall be used.

(B) Intercell and Intertier Conductors and Connec-

tions. The ampacity of field-assembled intercell and inter-

tier connectors and conductors shall be of such cross-

sectional area that the temperature rise under maximum

load conditions and at maximum ambient temperature shall

not exceed the safe operating temperature of the conductor

insulation or of the material of the conductor supports.

(C) Battery Terminals. Electrical connections to the bat-

tery, and the cable(s) between cells on separate levels or

racks, shall not put mechanical strain on the battery termi-

nals. Terminal plates shall be used where practicable.

Change Description: New Section provides requirements for antioxidant material used on battery terminals, correlates this section with Section 668.12(B), and addresses strain put on terminals by weight of cables. Impact(s) : No negative impact.

2

480.6 DC Disconnect Methods.

(B) Remote Actuation. Where controls to activate the dis-

connecting means of a battery are not located within sight

of a stationary battery system, the disconnecting means

Change Description: New subsections address requirements for remotely actuated DC disconnecting means, disconnect incorporated into a busway,

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shall be capable of being locked in the open position, in

accordance with 110.25, and the location of the controls

shall be field marked on the disconnecting means.

(C) Busway. Where a DC busway system is installed, the

disconnecting means shall be permitted to be incorporated

into the busway.

(D) Notification. The disconnecting means shall be legibly

marked in the field. A label with the marking shall be

placed in a conspicuous location near the battery if a dis-

connecting means is not provided. The marking shall be of

sufficient durability to withstand the environment involved

and shall include the following:

(1) Nominal battery voltage

(2) Maximum available short-circuit current derived from

the stationary battery system

(3) Date the calculation was performed

and marking of the disconnecting means. Impact(s) : No negative impact.

480.7 Insulation of Batteries of over 250 Volts. The pro-

visions of 480.6 shall apply to storage batteries having the

cells connected so as to operate at a nominal voltage ex-

ceeding 250 volts, and, in addition, the provisions of this

section shall also apply to such batteries. Cells shall be

installed in groups having a total nominal voltage of not

over 250 volts. Insulation, which can be air, shall be pro-

vided between groups and shall have a minimum separation

between live battery parts of opposite polarity of 50 mm

(2 in.) for battery voltages not exceeding 600 volts.

Change Description: This section was deleted due to its lack of clarity. In addition, it did not improve safety but was reducing the reliability of the battery systems. Impact(s) : No negative impact.

2

480.8 Racks and Trays.

(C) Accessibility. The terminals of all cells or multi-cell

units shall be readily accessible for readings, inspection,

and cleaning where required by the equipment design. One

side of transparent battery containers shall be readily acces-

sible for inspection of the internal components.

Change Description: Added definition clarifies expectations regarding accessibility of battery racks and trays for inspections. Impact(s) : No negative impact.

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480.9 Battery Locations. Battery locations shall conform

to 480.9(A), (B), and (C).

(A) Ventilation. Provisions appropriate to the battery tech-

nology shall be made for sufficient diffusion and ventilation

of the gases from the battery, if present, to prevent the

accumulation of an explosive mixture.

(C) Working Space.Spaces About Battery Systems.

Working space Spaces about the battery systems shall

comply with 110.26. Working clearancespace shall be

measured from the edge of the batteryrack cabinet, racks,

or trays.

For battery racks, there shall be a minimum clearance

of 25 mm (1 in.) between a cell container and any wall or

structure on the side not requiring access for maintenance.

Battery stands shall be permitted to contact adjacent walls

or structures, provided that the battery shelf has a free air

space for not less than 90 percent of its length.

Informational Note: Additional space is often needed to accommodate battery hoisting equipment, tray removal, or spill containment.

(D) Top Terminal Batteries. Where top terminal

batteries are installed on tiered racks, working space in

accordance with the battery manufacturer’s

instructions shall be provided between the highest

point on a cell and the row or ceiling above that

point.

Informational Note: Battery manufacturer’s installation instructions typically define how much top working space is necessary for a particular battery model.

(E) Egress. A personnel door(s) intended for entrance

to, and egress from, rooms designated as battery rooms

shall open in the direction of egress and shall be

equipped with listed panic hardware. (F) Piping in Battery Rooms. Gas piping shall not be

Change Description: This added language covers installation aspects which were originally addressed in NFPA 70E and deleted in 2009 edition of that code. This change was developed as a joint effort of the NEC DC Task Force and IEEE Stationary Battery Code Working Group. Impact(s) : No negative impact – improves safety.

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permitted in dedicated battery rooms. (G) Illumination. Illumination shall be provided for

working spaces containing battery systems. The

lighting outlets shall not be controlled by automatic

means only. Additional lighting outlets shall not be

required where the work space is illuminated by an

adjacent light source. The location of luminaires shall

not:

(1) Expose personnel to energized battery

components while performing maintenance on the

luminaires in the battery space; or

(2) Create a hazard to the battery upon failure of the

luminaire.

ARTICLE 490 Equipment Over 6001000 Volts, Nominal

490.21 Circuit-Interrupting Devices.

(B) Power Fuses and Fuseholders.

(6) Fuseholders. Fuseholders shall be designed or in-

stalled so that they are de-energized while a fuse is being

replaced. A field-applied permanent and legible sign, in ac-

cordance with 110.21(B), shall be installed immediately ad-

jacent to the fuseholders and shall be worded as follows:

DANGER — DISCONNECT CIRCUIT BEFORE RE-

PLACING FUSES.

Exception: Fuses and fuseholders designed to permit fuse

replacement by qualified persons using equipment designed

for the purposeidentified equipment without de-energizing

the fuseholder shall be permitted.

Change Description: Change associated with deletion of Section 225.70(A). Added requirement for a field label alerting the worker to the danger associated with replacing fuses. Impact(s) : No negative impact – improves safety.

2

490.25 Backfeed. Installations where the possibility of

backfeed exists shall comply with (a) and (b), which fol-

low.

(a) A permanent sign in accordance with 110.21(B)

Change Description: Modified the requirement originally provided in Section 225.70(A)(4) which was deleted in this edition of the code.

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shall be installed on the disconnecting means enclosure or

immediately adjacent to open disconnecting means with the

following words or equivalent: DANGER — CONTACTS

ON EITHER SIDE OF THIS DEVICE MAY BE ENER-

GIZED BY BACKFEED.

(b) A permanent and legible single-line diagram of the

local switching arrangement, clearly identifying each point

of connection to the high-voltage section, shall be provided

within sight of each point of connection.


490.35 Accessibility of Energized Parts.

(A) High-Voltage Equipment. Doors that would provide

unqualified persons access to high-voltage energized parts

shall be locked. Permanent signs in accordance with

110.21(B) shall be installed on panels or doors that provide

access to live parts over 1000 volts and shall read DAN-

GER — HIGH VOLTAGE — KEEP OUT

Change Description: Added the requirement originally provided in Section 225.70(A)(5) which was deleted in this edition of the code. Impact(s) : No negative impact.

1

490.47 Metal-Enclosed and Metal-CladSwitchgear

Used as Service Equipment. Metal-enclosed and metal-

clad switchgear Switchgear installed as high-voltage ser-

vice equipment shall include a ground bus for the connec-

tion of service cable shields and to facilitate the attachment

of safety grounds for personnel protection. This bus shall

be extended into the compartment where the service con-

ductors are terminated. Where the compartment door or

panel provides access to parts that can only be de-energized

and visibly isolated by the serving utility, the warning sign

required by 490.35(A) shall include a notice that access is

limited to the serving utility or is permitted only following

an authorization of the serving utility.

Change Description: Added and expanded the requirement originally provided in Section 225.70(A)(5) which was deleted in this edition of the code. Impact(s) : No negative impact.

2

490.48 Substation Design, Documentation, and Re-

quired Diagram.

(A) Design and Documentation. Substations shall be de-

signed by a qualified licensed professional engineer. Where

components or the entirety of the substation are listed by a

Change Description: Added and made editorial changes to the requirement originally provided in Section 225.70(A)(5) which was deleted in this edition of the code.

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qualified electrical testing laboratory, documentation of in-

ternal design features subject to the listing investigation

shall not be required. The design shall address but not be

limited to the following topics and the documentation of

this design shall be made available to the authority having

jurisdiction.

(1) Clearances and exits

(2) Electrical enclosures

(3) Securing and support of electrical equipment

(4) Fire protection

(5) Safety ground connection provisions

(6) Guarding live parts

(7) Transformers and voltage regulation equipment

(8) Conductor insulation, electrical and mechanical protec-

tion, isolation, and terminations

(9) Application, arrangement, and disconnection of circuit

breakers, switches, and fuses

(10) Provisions for oil filled equipment

(11) Switchgear

(12) Surge arrestors

(B) Diagram. A permanent, single-line diagram of the

switchgear shall be provided in a readily visible location

within the same room or enclosed area with the switchgear,

and this diagram shall clearly identify interlocks, isolation

means, and all possible sources of voltage to the installation

under normal or emergency conditions, and the marking on

the switchgear shall cross-reference the diagram.

Exception: Where the equipment consists solely of a single

cubicle or metal-enclosed unit substation containing only

one set of high-voltage switching devices, diagrams shall

not be required.


ARTICLE 500 Hazardous (Classified) Locations, Classes I, II, and III, Division 1 and 2

500.2 Definitions.

Combustible Dust. Any finely divided solid material that

is 420 microns (0.017 in.) or smaller in diameter (material

Change Description: Revised to align with the changed definition found in NFPA 499.

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passing a U.S. No. 40 Standard Sieve) and presents a fire or

explosion hazard when dispersed and ignited in air. [499,

2008]

Combustible Dust. Dust particles that are 500 microns or

smaller (material passing a U.S. No. 35 Standard Sieve as

defined in ASTM E 11-09, Standard Specification for Wire

Cloth and Sieves for Testing Purposes) and present a fire or

explosion hazard when dispersed and ignited in air.


500.5 Classifications of Locations.

(A) Classifications of Locations. Locations shall be clas-

sified depending on the properties of the flammable gas,

flammable liquid-–produced vapor, combustible liquid–

produced vapors, combustible dusts, or fibers/flyings that

may be present, and the likelihood that a flammable or

combustible concentration or quantity is present. Each

room, section, or area shall be considered individually in

determining its classification. Where pyrophoric materials

are the only materials used or handled, these locations shall

not be classified. Each room, section, or area shall be con-

sidered individually in determining its classification.are

outside the scope of this article.

Change Description: Clarified the original intent of this section. Impact(s) : No negative impact.

1

500.8 Equipment. Articles 500 through 504 require equip-

ment construction and installation that ensure safe perfor-

mance under conditions of proper use and maintenance.

(C) Marking. Equipment shall be marked to show the en-

vironment for which it has been evaluated. Unless other-

wise specified or allowed in (C)(6), the marking shall in-

clude the information specified in (C)(1) through (C)(5).

(4) Equipment Temperature. 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 ambient tem-

perature of greater than 40°C. For equipment installed in a

Class II, Division 1 location, the temperature class or oper-

ating temperature shall be based on operation of the equip-

Change Description: Clarified the requirements for defining temperature class as referring to operating temperature when blanketed with dust. Impact(s) : No negative impact.

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ment when blanketed with the maximum amount of dust

that can accumulate on the equipment. The temperature

class, if provided, shall be indicated using the temperature

class (T Codes)codes) shown in Table 500.8(C). Equipment

for Class I and Class II shall be marked with the maximum

safe operating temperature, as determined by simultaneous ex-

posure to the combinations of Class I and Class II conditions.

ARTICLE 501 Class I Locations

501.10 Wiring Methods. Wiring methods shall comply

with 501.10(A) or (B).

(A) Class I, Division 1.

(1) General. In Class I, Division 1 locations, the wiring

methods in (a) through (d)(e) shall be permitted.

e) Optical fiber cable Types OFNP, OFCP, OFNR,

OFCR, OFNG, OFCG, OFN, and OFC shall be permitted

to be installed in raceways in accordance with 501.10(A).

These optical fiber cables shall be sealed in accordance

with 501.15.

(2) Flexible Connections. Where necessary to employ

flexible connections, as at motor terminals, the following

shall be permitted:

(1) fFlexible fittings listed for the location, or

(2) fFlexible cord in accordance with the provisions of

501.140, terminated with cord connectors listed for the

location, shall be permitted. or

(3) In industrial establishments with restricted public ac-

cess, where the conditions of maintenance and supervision

ensure that only qualified persons service the installation,

for applications limited to 600 volts, nominal, or less,

and where protected from damage by location or a suitable

guard, listed Type TC-ER-HL cable with an overall jacket

and a separate equipment grounding conductor(s) in

accordance with 250.122 that is terminated with fittings

listed for the location

Change Description: Added a requirement for correlation with Chapter 7 which allows the listed optical fiber cables in classified locations if sealed per Chapter 5 requirements. In addition, the new subsection adds TC-ER-HL cable as an acceptable wiring method for industrial applications where flexibility is required. This cable is approved for use in classified locations per UL 2225. Impact(s) : No negative impact.

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with 501.10(A) or (B).

(B) Class I, Division 2.

(1) General. In Class I, Division 2 locations, the following

wiring methods shall be permitted:

(7) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR,

OFNG, OFCG, OFN, and OFC shall be permitted to be

installed in cable trays or any other raceway in accordance

with 501.10(B). Optical fiber cables shall be sealed in

accordance with 501.15.

(2) Flexible Connections. Where provision must be made

for limited flexibility, one or more of the following shall be

permitted:

(3) Interlocked armor Type MC cable with listed fittings.

(7) For elevator use, an identified elevator cable of Type

EO, ETP, or ETT, shown under the “use” column in

Table 400.4 for “hazardous (classified) locations” and

terminated with listed fittings.

Change Description: Added a requirement for correlation with Chapter 7 which allows the listed optical fiber cables in classified locations if sealed per Chapter 5 requirements. The added subsection 501.10(B)(2)(3) adds to the acceptable wiring methods the MC cable already listed in 510.(A)(1). Also, the change under subsection 501.10(B)(2)(7) correlates the requirements with Chapter 4. Impact(s) : No negative impact.

2

501.15 Sealing and Drainage. Seals in conduit and cable

systems shall comply with 501.15(A) through (F). Sealing

compound shall be used in Type MI cable termination fit-

tings to exclude moisture and other fluids from the cable

insulation.

(A) Conduit Seals, Class I, Division 1. In Class I, Divi-

sion 1 locations, conduit seals shall be located in accor-

dance with 501.15(A)(1) through (A)(4).

(1) Entering Enclosures. In each Each conduit entry

into an explosionproof enclosure shall have a conduit

seal where either of the following apply: conditions

applies:

(1) The enclosure contains apparatus, such as switches, cir-

cuit breakers, fuses, relays, or resistors, that may pro-duce

arcs, sparks, or high temperatures that are considered to be

an ignition sourceexceed 80 percent of the autoignition

Change Description: Revised to clarify language and for consistency with the NEC Style Manual. Impact(s) : No negative impact.

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temperature, in degrees Celsius, of the gas or vapor

involved in normal operation.

Exception: Seals shall not be required for conduit entering

an enclosure under any one of the following conditions: a. The switch, circuit breaker, fuse, relay, or resistor is

enclosed within a chamber hermetically sealed against

the entrance of gases or vapors.

b. The switch, circuit breaker, fuse, relay, or resistor is

immersed in oil in accordance with 501.115(B)(1)(2).

c. The switch, circuit breaker, fuse, relay, or resistor is

enclosed within a factory-sealed explosionproof cham-

ber located within the enclosure, identified for the lo-

cation, and marked “factory sealed” or equivalent.

d. The switch, circuit breaker, fuse, relay, or resistor is

part of a nonincendive circuit.

(2) The entry is metric designator 53 (trade size 2) or

larger, and the enclosure contains terminals, splices, or

taps.

For the purposes of this section, high temperatures shall

be considered to be any temperatures exceeding 80 percent

of the autoignition temperature in degrees Celsius of the

gas or vapor involved.

Exception to 501.15(A)(1)(1): Seals shall not be required

for conduit entering an enclosure where such switches, cir-

cuit breakers, fuses, relays, or resistors comply with one of

the following: (1) Are enclosed within a chamber hermetically sealed

against the entrance of gases or vapors

(2) Are immersed in oil in accordance with

501.115(B)(1)(2)

(3) Are enclosed within a factory-sealed explosionproof

chamber located within the enclosure, identified for the

ocation, and marked “factory sealed” or equivalent,

unless the enclosure entry is metric designator 53



of 203

(trade size 2) or larger

(4) Are in nonincendive circuits





insulation.

(A) Conduit Seals, Class I, Division 1. In Class I, Divi-


dance with 501.15(A)(1) through (A)(4).

4) Class I, Division 1 Boundary. In A conduit seal shall

be required in each conduit run leaving a Class I, Division

1 location. The sealing fitting shall be permitted to be installed on either side of the boundary and it shall be de- within 3.05 m (10 ft) of the boundary, and it shall be de-

signed and installed so as to minimize the amount of gas or

vapor within the Division 1 portion of the conduit from

being communicated to the conduit installed in the Division1

location that can be communicated beyond the seal. Ex-

cept for listed explosionproof reducers The conduit run be-

tween the conduit seal and the point at which at the conduit

seal, there leaves the Division 1 location shall becontain no

union, coupling, box, or other fitting between the conduit

seal and the pointexcept for a listed explosionproof reducer

installed at which the conduit leaves the Division 1 loca-

tion.seal.


1





insulation.

(B) Conduit Seals, Class I, Division 2. In Class I, Divi-


dance with 501.15(B)(1) and (B)(2).

(2) Class I, Division 2 Boundary. In A conduit seal shall


1



of 203

be required in each conduit run passing from leaving a

Class I, Division 2 location into an unclassified location.

The sealing fitting shall be permitted to be installed on

either side of the boundary of such location within 3.05 m

(10 ft) of the boundary and it shall be designed and in-

stalled to minimize the amount of gas or vapor within the

portion of the conduit installed in the Division 2 location

that can be communicated beyond the seal. Rigid metal

conduit or threaded steel intermediate metal conduit shall

be used between the sealing fitting and the point at which

the conduit leaves the Division 2 location, and a threaded

connection shall be used at the sealing fitting. Except for

listed reducers at the conduit seal, there shall be no union,

coupling, box, or fitting The conduit run between the con-

duit seal and the point at which the conduit leaves the

Division 2 location. Conduits shall be sealed to minimize

the amount of gas or vapor within the Division 2 portion of

the conduit from being communicated to location shall con-

tain no union, coupling, box, or other fitting except for a

listed explosionproof reducer installed at the conduit be-

yond the seal. Such seals shall not be required to be explo-

sionproof but shall be identified for the purpose of mini-

mizing the passage of gases permitted under normal

operating conditions and shall be accessible.





insulation.

(D) Cable Seals, Class I, Division 1. In Class I, Division 1 locations, cable seals shall be located according to 501.15(D)(1) through (D)(3). 2) Cables Capable of Transmitting Gases or Vapors.

Cables in conduit with a gas/vaportight continuous sheath

capable of transmitting gases or vapors through the cable

core, installed in conduit, shall be sealed in the Class 1,

Division 1 location after removing the jacket and any other

coverings have been removed so that the sealing compound


1



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willcan surround each individual insulated conductor or op-

tical fiber tube and the outer jacket.

Exception: Multiconductor cables with a gas/vaportight

continuous sheath capable of transmitting gases or vapors

through the cable core shall be permitted to be considered

as a single conductor by sealing the cable in the conduit

within 450 mm (18 in.) of the enclosure and the cable end

within the enclosure by an approved means to minimize the

entrance of gases or vapors and prevent the propagation of

flame into the cable core, or by other approved methods.

For shielded cables and twisted pair cables, it It shall not

be required to remove the shielding material or separate

the twisted pairs of shielded cables and twisted pair cables.





insulation.

(E) Cable Seals, Class I, Division 2. In Class I, Division 2

locations, cable seals shall be located in accordance with

501.15(E)(1) through (E)(4).

Exception: Cables with an unbroken gas/vaportight con-

tinuous sheath shall be permitted to pass through a Divi-

sion 2 location without seals.

(1) Terminations. Cables entering enclosures that are re-

quired to be explosionproof shall be sealed at the point of

entrance. The sealing fitting shall comply with

01.15(B)(1) or be explosionproof. Multiconductor or op-

tical multifiber cables with a gas/vaportight continuous

sheath capable of transmitting gases or vapors through the

cable core shall be sealedthat are installed in a listed fitting

in the Division 2 location after removing Division 2 loca-

tion shall be sealed with a listed fitting after the jacket and

any other coverings have been removed so that the sealing

compound can surrounds each individual insulated conduc-

tor or optical fiber tube in such a manner as to minimize the

passage of gases and vapors. Multiconductor or optical

Change Description: Revised to clarify language and for consistency with the NEC Style Manual. Also, added an exception allowing cables with unbroken gas/vaportight continuous sheath to pass through Div. 2 location without seals and expanded to include seals of fiber optic cables. Impact(s) : No negative impact.

2



of 203

multifiber cables installed in conduit shall be sealed as de-

scribed in 501.15(D).

2) Cables That Do Not Transmit Gases or Vapors.

Cables that have a gas/vaportight continuous sheath and do

not transmit gases or vapors through the cable core in ex-

cess of the quantity permitted for seal fittings shall not be

required to be sealed except as required in 501.15(E)(1).

The minimum length of such a cable run shall not be less

than thatthe length that limits needed to limit gas or vapor

flow through the cable core, excluding the interstices of the

conductor strands, to the rate permitted for seal fittings

[200 cm3/hr (0.007 ft3/hr) of air at a pressure of 1500 pas-

cals (6 in. of water)].





insulation.

(F) Drainage.

(2) Motors and Generators. Where the authority having

jurisdiction judges that there is a probability that liquid or

condensed vapor may accumulate within motors or genera-

tors, joints and conduit systems shall be arranged to mini-

mize the entrance of liquid. If means to prevent accumula-

tion or to permit periodic draining are judged necessary,

such means shall be provided at the time of manufacture

and shall be considered an integral part of the machine.

Change Description: This change removed ambiguity of the language in this section. Impact(s) : No negative impact – improves safety.

2

501.17 Process Sealing. This section shall apply to

process-connected equipment, which includes, but is not

limited to, canned pumps, submersible pumps, flow, pres-

sure, temperature, or analysis measurement instruments. A

process seal is a device to prevent the migration of process

fluids from the designed containment into the external elec-

trical system. Process-connected electrical equipment that

incorporates a single process seal, such as a single com-

pression seal, diaphragm, or tube to prevent flammable or

Change Description: This change correlates the requirements with ANSI/ISA-12.27.01. Impact(s) : No negative impact.

2



of 203

combustible fluids from entering a conduit or cable system

capable of transmitting fluids, shall be provided with an

additional means to mitigate a single process seal failure,

The additional means may include, but is not limited to, the

following:

(4) An add-on secondary seal marked “secondary seal” and

rated for the pressure and temperature conditions to which

it will be subjected upon failure of the single process seal.

501.30 Grounding and Bonding, Class I, Divisions 1

and 2. Wiring Regardless of the voltage of the electrical

system, 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).

Change Description: This change clarifies the applicability of this section. Impact(s) : No negative impact.

1

501.40 Multiwire Branch Circuits. In a Class I, Division

1 location, a multiwire branch circuit shall not be permit-

ted.

Exception: Where the disconnect device(s) for the circuit

opens all ungrounded conductors of the multiwire circuit

simultaneously.

Change Description: The requirements found in this deleted section are already included in 210.4(B) and do not need to be repeated here. Impact(s) : No negative impact.

1

501.105 Meters, Instruments, and Relays.

(B) Class I, Division 2. In Class I, Division 2 locations,

meters, instruments, and relays shall comply with

501.105(B)(1) through (B)(6).

(6) Connections. To facilitate replacements, process con-

trol instruments shall be permitted to be connected through

flexible cord, 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.

Exception: The switch is not required if the circuit is non-

incendive field wiring.

Change Description: The added exception eliminates the requirement for a switch in a circuit with a connection plug for nonincendive field wiring. Nonincendive wiring is not capable of igniting flammable mixtures and a switch in this case is not required. Impact(s) : No negative impact.

2



of 203

501.130 Luminaires. Luminaires shall comply with

501.130(A) or (B).

(B) Class I, Division 2. In Class I, Division 2 locations,

luminaires shall comply with 501.130(B)(1) through (B)(6).

(4) Portable Lighting Equipment. Portable lighting

equipment shall comply with 501.130(A)(1).

Exception: Where portable lighting equipment is mounted

on movable stands and is connected by flexible cords, as

covered in 501.140, it shall be permitted to comply with

501.130(B)(1), where mounted in any position, if provided

that it conforms to also complies with 501.130(B)(2).

Change Description: The change clarifies the language of this exception. Impact(s) : No negative impact.

1

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

Permitted Uses. Flexible cord shall be permitted:

(1) 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

the protection technique of the equipment wiring

compartment. An attachment plug in accordance with

501.140(B)(4) shall be employed.

Change Description: Revised to make clear that 501.140(A)(1) covers power cords that attach to the utilization equipment with a cord connector and have an attachment plug for connection to premises wiring. Impact(s) : No negative impact.

1

501.145 Receptacles and Attachment Plugs, Class I, Di-

visions 1 and 2. Receptacles and 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.

(A) Receptacles. Receptacles shall be part of the premises

wiring, except as permitted by 501.140(A). (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.

Change Description: Revised to make clear that the receptacle is part of the premises wiring and that the attachment plug is part of the utilization equipment. Impact(s) : No negative impact.

1

ARTICLE 502



of 203

Class II Locations 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 (4) 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 E locations, shall be identified for

Class II locations.

(4) Optical fiber cables Types OFNP, OFCP, OFNR,

OFCR, OFNG, OFCG, OFN, and OFC shall be permit-

ted to be installed in raceways in accordance with

502.10(A). Optical fiber cables shall be sealed in


6) For elevator use, an identified elevator cable of Type


Table 400.4 for “hazardous (classified) locations” and

terminated with listed dusttight fittings.

Change Description: Added a requirement for correlation with Chapter 7 which allows the listed optical fiber cables in classified locations if sealed per Chapter 5 requirements. Also, the change under subsection 502.10(A)(1)(6) correlates the requirements with Chapter 4. Impact(s) : No negative impact.

2


with 502.10(A) or (B).

(A) Class II, Division 1.

(3) Boxes and Fittings. Boxes and fittings shall be pro-

vided with threaded bosses for connection to conduit or

cable terminations and shall be dusttight. Boxes and fittings

in which taps, joints, or terminal connections are made, or

that are used in Group E locations, shall be identified for

Class II locations.

Change Description: Editorial change – relocated from 502.10(A)(1)(4). Impact(s) : No negative impact.

1


with 502.10(A) or (B).

(B) Class II, Division 2.

Change Description: Added a requirement for correlation with Chapter 7 which allows the listed optical fiber cables in classified locations if sealed per

2



of 203

(1) General. In Class II, Division 2 locations, the follow-

ing wiring methods shall be permitted:

(6) Type MC, MI, or TC cable installed in ladder, venti-

lated 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 method employed.

Exception to (6): Type MC cable listed for use in Class II,

Division 1 locations shall be permitted to be installed with-

out the spacings required by (6).

8) Optical fiber cable Types OFNP, OFCP, OFNR, OFCR,


installed in cable trays or any other raceway in accor-

dance with 502.10(B). Optical fiber cables shall be

sealed in accordance with 502.15.

Exception to (6): Type MC cable listed for use in Class II,

Division 1 locations shall be permitted to be installed with-

out the spacings required by (6).

Chapter 5 requirements. Impact(s) : No negative impact.

502.30 Grounding and Bonding, Class II, Divisions 1

and 2. Wiring Regardless of the voltage of the electrical

system, wiring and equipment in Class II, Division 1 and 2

locations shall be grounded as specified in Article 250 and in

accordance with the requirements of 502.30(A) and (B).


1

502.40 Multiwire Branch Circuits. In a Class II, Division

1 location, a multiwire branch circuit shall not be permit-

ted.



simultaneously.


1

502.125 Motors and Generators.

(A) Class II, Division 1. In Class II, Division 1 locations,

motors, generators, and other rotating electrical machinery

Change Description: Editorial change.

1



of 203

shall be in conformance with either of the following:

(1) Identified for the location

(2) Totally enclosed pipe-ventilated, meeting temperature

limitations in 502.5pipe-ventilated


502.140 Flexible Cords — Class II, Divisions 1 and 2.

(A) Permitted Uses. Flexible cords used in Class II loca-

tions shall comply with all of the following:

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

between portable lighting equipment or other portable

utilization equipment and the fixed portion of its supply

circuit. The flexible cord shall be attached to the utili-

zation equipment with a cord connector listed for the

protection technique of the equipment wiring compart-

ment. An attachment plug in accordance with 502.145

shall be employed.

(2) Where flexible cord is permitted by 502.10(A)(2) for

fixed and mobile electrical utilization equipment;

where the flexible cord is protected by location or by a

suitable guard from damage; and only in an industrial

establishment where conditions of maintenance and en-

gineering supervision ensure that only qualified persons

install and service the installation.

(3) For electric submersible pumps with means for re-

moval 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 recep-

tacles, switches, and other devices that are not consid-

ered portable utilization equipment but are individually

listed for the location.

(B) Installation. Where flexible cords are used, the cords

shall comply with all of the following:

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

Change Description: Revised to make clear that 502.140(A) covers power cords that attach to the utilization equipment with a cord connector and have an attachment plug for connection to premises wiring. It mirrors changes to Section 501.140. Impact(s) : No negative impact.

1



of 203

5) Be of continuous length. Where 502.140(A)(5) is ap-

plied, 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.

502.145 Receptacles and Attachment Plugs. Receptacles

and attachment plugs shall be identified for the location.

(A) Class II, Division 1.

(1) Receptacles. In Class II, Division 1 locations, recep-

tacles and attachment 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.

part of the premises wiring.

(2) Attachment Plugs. Attachment plugs shall be of the

type that provides for connection to the equipment ground-

ing conductor of the flexible cord.

(B) Class II, Division 2.

(1) Receptacles. In Class II, Division 2 locations, recep-

tacles and attachment plugs shall be of the type that pro-

vides for connection to the equipment grounding conductor

of the flexible cord and shall be designed so that connection

to the supply circuit cannot be made or broken while live

parts are exposed.part of the premises wiring.

(2) Attachment Plugs. Attachment plugs shall be of the

type that provides for connection to the equipment ground-

ing conductor of the flexible cord.

Change Description: Revised to make clear that the receptacle is part of the premises wiring and that the attachment plug is part of the utilization equipment. Impact(s) : No negative impact.

1

ARTICLE 503 Class III Locations

503.5 General. Equipment installed in Class III locations

shall be able to function at full rating without developing

surface temperatures high enough to cause excessive dehy-

dration or gradual carbonization of accumulated

fibers/flyings. Organic material that is carbonized or exces-

Change Description: Clarified the requirements for defining temperature class as referring to operating temperature when blanketed with dust (simulating fibers/flyings).

2



of 203

sively dry is highly susceptible to spontaneous ignition.

The maximum surface temperatures under operating condi-

tions shall not exceed 165°C (329°F) for equipment that is

not subject to overloading, and 120°C (248°F) for equip-

ment (such as motors or power transformers) that may be

overloaded. In a Class III, Division 1 location, the operat-

ing temperature shall be the temperature of the equipment

when blanketed with the maximum amount of dust (simu-

lating fibers/flyings) that can accumulate on the equipment.



with 503.10(A) or (B).

(A) Class III,

Division 1.

(1) General. In Class III, Division 1 locations, the wiring

method shall be in accordance with (1) through (4):

(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

cable diameter between the two adjacent cables, shall

be the wiring method employed. The cable shall be

terminated with listed fittings.

(3) Flexible Connections. Where necessary to employ

flexible connections, one or more of the following shall be

permitted:

(6) For elevator use, an identified elevator cable of Type


Table 400.4 for “hazardous (classified) locations”

and terminated with listed dusttight fittings.

Change Description: The change under subsection 503.10(A)(3)(6) correlates the requirements with Chapter 4. Impact(s) : No negative impact.

1

503.30 Grounding and Bonding — Class III, Divisions

1 and 2. Wiring Regardless of the voltage of the electrical

system, wiring and equipment in Class III, Division 1 and 2

locations shall be grounded as specified in Article 250 and

with the following additional requirements in 503.30(A)

and (B).


1



of 203

ARTICLE 504 Intrinsically Safe Systems

504.30 Separation of Intrinsically Safe Conductors.

(A) From Nonintrinsically Safe Circuit Conductors.

(2) Within Enclosures. Conductors 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 from

conductors of nonintrinsically safe circuits by one of the

methods in (1) through (4).

(3) Separation from conductors of nonintrinsically safe cir-

cuits by use of an approved insulating partition. that

extends to within 1.5 mm (0.0625 in.) of the enclosure

walls

C) From Grounded Metal. The clearance between the

uninsulated parts of field wiring conductors connected to

terminals and grounded metal or other conducting parts

shall be at least 3 mm (0.125 in.).

Change Description: Expanded separation requirement between nonintrinsically safe and intrinsically safe circuits to include specific dimensions for the partition. Impact(s) : No negative impact.

2

ARTICLE 505 Zone 0, 1, and 2 Locations

505.5 Classifications of Locations.

(A) Classification of Locations. Locations shall be classi-

fied depending on the properties of the flammable vapors,

liquids, or gases flammable gases, flammable liquid–

produced vapors, combustible liquid–produced vapors,

combustible dusts, or fibers/flyings that may be present and

the likelihood that a flammable or combustible concentra-

tion or quantity is present. Each room, section, or area shall

be considered individually in determining its classification.

Where pyrophoric materials are the only materials used or

handled, these locations shall not be classified. Each room,

Change Description: Clarified the original intent of this section. Impact(s) : No negative impact.

1



of 203

section, or area shall be considered individually in deter-

mining its classification.are outside the scope of this article.

505.6 Material Groups. For purposes of testing, approval,

and area classification, various air mixtures (not oxygen

enriched) shall be grouped as required in 505.6(A), (B), and

(C).

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.”

Change Description: The second paragraph was redundant and was deleted from this section. Impact(s) : No negative impact.

1

505.7 Special Precaution. Article 505 requires equipment

construction and installation that ensures safe performance

under conditions of proper use and maintenance.

(F) Available Short-Circuit Current for Type of Protec-

tion “e”. The available short-circuit current for electrical

equipment using type of protection “e” for the field wiring

connections in Zone 1 locations shall be limited to 10,000

rms symmetrical amperes to reduce the likelihood of igni-

tion of a flammable atmosphere by an arc during a short-

circuit event.

Change Description: Added short circuit current requirements to correlate this subsection with ANSI/UL 508A, Standard for Industrial Control Panels. Impact(s) : No negative impact.

2

505.9 Equipment. (C) Marking. Equipment shall be marked in accordance

with 505.9(C)(1) or (C)(2).

(2) Zone Equipment. Equipment meeting one or more of

the protection techniques described in 505.8 shall be

marked with all of the following in the order shown:

(5) Applicable gas classification group(s) material group in

accordance with Table 505.9(C)(1)(2) or a specific gas

or vapor

Exception No. 3: Fittings for the termination of cables

shall not be required to have a marked operating tempera-

ture or temperature class.

Electrical equipment of types of protection “e,” “m,” “ma,”

“mb,” “px,” “py,” “pz,” or “q” shall be marked Group

Change Description: Modified language for consistency in used terms. Cable fittings are not required by ANSI/UL 2225 to be marked with a temperature class. Also, since product standards have been revised such that the marking of the Group subdivision is always required, text covering marking was no longer necessary. Impact(s) : No negative impact.

1



of 203

II. Electrical equipment of types of protection “d,” “ia,”

“ib,” “ic,” [ia],” “[ib],” or “[ic]” shall be marked Group

IIA, IIB, or IIC, or for a specific gas or vapor. Electrical

equipment of types of protection “n” shall be marked Group

II unless it contains enclosed-break devices, nonincendive

components, or energy-limited equipment or circuits, in

which case it shall be marked Group IIA, IIB, or IIC, or a

specific gas or vapor. Electrical equipment of other types of

protection shall be marked Group II unless the type of

protection utilized by the equipment requires that it be

marked Group IIA, IIB, or IIC, or a specific gas or vapor.

505.15 Wiring Methods. Wiring methods shall maintain

the integrity of protection techniques and shall comply with

505.15(A) through (C).

(B) Class I, Zone 1.

(1) General. In Class I, Zone 1 locations, the wiring meth-

ods in (B)(1)(a) through (B)(1)(fi) shall be permitted.

(g) Intrinsic safety type of protection “ib” shall be

permitted using the wiring methods specified in Article

504.

(h) Optical fiber cable Types OFNP, OFCP, OFNR,


to be installed in raceways in accordance with 505.15(B).

Optical fiber cable shall be sealed in accordance with

505.16.

(i) In industrial establishments with restricted public

access, where the conditions of maintenance and supervi-

sion ensure that only qualified persons service the installa-

tion, for applications limited to 600 volts nominal or less,

for cable diameters 25 mm (1 in.) or less, and where the

cable is not subject to physical damage, Type TC-ER-HL

cable listed for use in Class I, Zone 1 locations, with an

overall jacket and a separate equipment grounding conduc-

tor(s) in accordance with 250.122, and terminated with fit-

tings listed for the location, Type TC-ER-HL cable shall be

installed in accordance with the provisions of Article 336,

Change Description: Added a requirement for correlation with Chapter 7 which allows the listed optical fiber cables in classified locations if sealed per Chapter 5 requirements. In addition, the new subsection adds TC-ER-HL cable as an acceptable wiring method for industrial applications where flexibility is required. This cable is approved for use in classified locations per UL 2225. Impact(s) : No negative impact.

2



of 203

including the restrictions of 336.10(7).




(C) Class I, Zone 2. (1) General. In Class I, Zone 2 locations, the following wiring

methods shall be permitted.

(h) Optical fiber cable of Types OFNP, OFCP, OFNR,


to be installed in cable trays or any other raceway in accor-

dance with 505.15(C). Optical fiber cable shall be sealed in


Change Description: Added a requirement for correlation with Chapter 7 which allows the listed optical fiber cables in classified locations if sealed per Chapter 5 requirements. Impact(s) : No negative impact.

2




(C) Class I, Zone 2.

(2) Flexible Connections. Where provision must be made

for limited flexibility, flexible metal fittings, flexible metal

conduit with listed fittings, liquidtight flexible metal con-

duit with listed fittings, liquidtight flexible nonmetallic con-

duit with listed fittings, or flexible cord in accordance with

the provisions of 505.17 terminated with a listed cord con-

nector that maintains the type of protection of the terminal

compartment shall be permitted.

Exception: For elevator use, an identified elevator cable

of Type EO, ETP, or ETT, shown under the “use” column in

Table 400.4 for “hazardous (classified) locations,” that is

terminated with listed connectors that maintain the type of

protection of the terminal compartment, shall be permitted.

Change Description: The change under subsection 505.15(C)(2) correlates the requirements with Chapter 4. Impact(s) : No negative impact.

1


systems shall comply with 505.16(A) through (E). Sealing



insulation.

(B) Zone 1. In Class I, Zone 1 locations, seals shall be located

Change Description: Expanded language to include seals of fiber optic cables. Impact(s) : No negative impact.

2



of 203

in accordance with 505.16(B)(1) through (B)(8).

(5) Cables Capable of Transmitting Gases or Vapors.

Conduits containing cables with a gas/vaportight continu-

ous sheath capable of transmitting gases or vapors through

the cable core shall be sealed in the Zone 1 location after

removing the jacket and any other coverings so that the

sealing compound surrounds each individual insulated con-

ductor or optical fiber tube and the outer jacket.

(6) Cables Incapable of Transmitting Gases or Vapors.

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 or

vapors through the cable core. These cables shall be sealed

in accordance with 505.16(D).





insulation.

(C) Zone 2. In Class I, Zone 2 locations, seals shall be

located in accordance with 505.16(C)(1) and (C)(2).

(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 or

explosionproof shall be sealed at the point of entrance. The

seal shall comply with 505.16(D). Multiconductor or opti-

cal multifiber cables with a gas/vaportight

continuous sheath capable of transmitting gases or vapors

through the cable core shall be sealed in the Zone 2

location after removing the jacket and any other

coverings so that the sealing compound surrounds each

individual insulated conductor or optical fiber tube in

such a manner as to minimize the passage of gases and

vapors. Multiconductor or optical multifiber cables in

conduit shall be sealed as described in


2



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505.16(B)(4).





insulation.

(D) Class I, Zones 0, 1, and 2. Where required, seals in

Class I, Zones 0, 1, and 2 locations shall comply with

505.16(D)(1) through (D)(5).

(5) Conductor or Optical Fiber Fill. 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 the

same trade size unless it is specifically listed for a higher

percentage of fill.


2

505.17 Flexible Cords and Connections.

B) Instrumentation Connections for Zone 2. To facili-

tate replacements, process control instruments shall be per-

mitted to be connected through flexible cords, attachment

plugs, and receptacles, provided that all of the following

conditions apply:

(1) A switch listed for Zone 2 is provided so that the at-

tachment plug is not depended on to interrupt current,

unless the circuit is type “ia,” “ib,” or “ic” protection,

in which case 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

ttachment plug and receptacle of the locking and

grounding type.

(4) Only necessary receptacles are provided.

(5) The receptacle carries a label warning against unplug-

ging under load.

Change Description: This added subsection provides requirements for instrumentation connections, applicable to Zone 2 locations. Impact(s) : No negative impact.

2



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505.20 Equipment Requirements.

(D) Materials. Equipment marked Group IIC shall be per-

mitted for applications requiring Group IIA or Group IIB

equipment. Similarly, equipment marked Group IIB shall

be permitted for applications requiring Group IIA equip-

ment.

Equipment marked for a specific gas or vapor shall be

permitted for applications where the specific gas or vapor

may be encountered.

Change Description: This change addresses the suitability of equipment marked with the chemical formula of a specific material. Although clear in the product standards, it is not clear in Article 505 that IIC equipment is suitable for applications requiring IIA or IIB equipment. Similarly, it is not clear that IIB equipment is suitable for applications requiring IIA equipment. Impact(s) : No negative impact.

1

505.21 Multiwire Branch Circuits. In a Class I, Zone 1

location, a multiwire branch circuit shall not be permitted.



simultaneously.


1

505.25 Grounding and Bonding. Regardless of the volt-

age of the electrical system, Ggrounding and bonding shall

comply with Article 250 and the requirements in 505.25(A)

and (B).


1

505.26 Process Sealing. This section shall apply to

process-connected equipment, which includes, but is not

limited to, canned pumps, submersible pumps, flow, pres-

sure, temperature, or analysis measurement instruments. A

process seal is a device to prevent the migration of process

fluids from the designed containment into the external elec-

trical system. Process connected electrical equipment that

incorporates a single process seal, such as a single com-

pression seal, diaphragm, or tube to prevent flammable or

Change Description: This change correlates the requirements with ANSI/ISA-12.27.01. Impact(s) : No negative impact.

2



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combustible fluids from entering a conduit or cable system

capable of transmitting fluids, shall be provided with an

additional means to mitigate a single process seal failure.

The additional means may include, but is not limited to the

following:

(4) An add-on secondary seal marked “secondary seal” and

rated for the pressure and temperature conditions to which

it will be subjected upon failure of the single process seal.

ARTICLE 506 Zone 20, 21, and 22 Locations for Combustible Dusts or Ignitible Fibers/Flyings

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 and

wiring for all voltages in Zone 20, Zone 21, and Zone 22

hazardous (classified) locations where fire and explosion

hazards may exist due to combustible dusts or ignitible

fibers/flyings. Combustible metallic dusts are not covered

by the requirements of this article.


1

Combustible Dust. Any finely divided solid material Dust

particles that is 420are 500 microns (0.017 in.) or smaller in

diameter (material passing a U.S. No. 4035 Standard Sieve)

Sieve as defined in ASTM E 11-09, Standard Specification

for Wire Cloth and Sieves for Testing Purposes) and pre-

sents a fire or explosion hazard when dispersed and ignited

in air. [499:3.3.3]

Change Description: Revised to align with the changed definition found in NFPA 499. Impact(s) : No negative impact.

2

506.3 Other Articles. All other applicable rules contained

in this Code shall apply to electrical equipment and wiring

installed in hazardous (classified) locations.

Exception: As modified by Article 504 and this article.

Change Description: Added clarification regarding applicability of other articles in the Code to this article. Impact(s) : No negative impact.

1



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506.6 Material Groups. For the purposes of testing, ap-

proval, 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.

(B) Group IIIB. Combustible dust other than combustible

metal dust.

(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

weight.

Change Description: Added dust groups to properly provide criteria for selection and application of the currently manufactured equipment. Impact(s) : No negative impact.

2

506.8 Protection Techniques. Acceptable protection tech-

niques for electrical and electronic equipment in hazardous

(classified) locations shall be as described in 506.8(A)

through (J).

(C) Intrinsic Safety. This protection technique shall be

permitted for equipment in Zone 20, Zone 21, and Zone 22

locations for which it is identified. Installation of intrinsi-

cally safe apparatus and wiring shall be in accordance with the

requirements of Article 504.

(HG) Protection by Enclosure “tD”.“t”. This protection

technique shall be permitted for equipment in Zone 2120,

Zone 21, and Zone 22 locations for which it is identified.

Change Description: Relocated requirements for intrinsically safe apparatus to Section 506.15. Also, revised enclosure marking to correlate with ANSI/ISA-60079-31 and ANSI/ISA-61241-1. Impact(s) : No negative impact.

1


(C) Marking.

(1) Division Equipment. Equipment identified for Class

II, Division 1 or Class II, Division 2 shall, in addition to

being marked in accordance with 500.8(C), be permitted to

be marked with bothall of the following:

(2) Temperature classificationMaterial group in accordance

with 506.9(D)506.6

(3) 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”

Change Description: This change adds requirements for marking dust groups, necessary for proper selection of equipment. Also, revised Table 506.9(C)(2)(3) to add new designations per ISA 60079-11. Added exception for associated intrinsically safe apparatus not exposed to combustible dust, not requiring a temperature classification. This is already addressed for gases in 505.9(B)(2) Exception 1. Impact(s) :

2



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(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 TMaterial group in

accordance with 506.6

(5) 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”

(56)Ambient temperature marking in accordance with

506.9(D)

Exception: Associated apparatus NOT suitable for instal-

lation in a hazardous (classified) location shall be required

to be marked only with 506.9(C)(2)(2), (3), and (5), but

BOTH the symbol AEx in 506.9(C)(2)(2) and the symbol for

the type of protection in 506.9(C)(2)(3) shall be enclosed

within the same square brackets; for example, [AEx iaD]

or [AEx ia] IIIC.

No negative impact.


(D) Temperature Classifications. Equipment shall be

marked to show the operating maximum surface tempera-

ture referenced to a 40°C (104°F) ambient. ambient, or at

the higher marked ambient temperature if the equipment is

rated and marked for an ambient temperature of greater

than 40°C. For equipment installed in a Zone 20 or Zone 21

location, the operating temperature shall be based on opera-

tion of the equipment when blanketed with the maximum

amount of dust (or with dust-simulating fibers/flyings) that

can accumulate on the equipment. Electrical equipment de-

signed for use in the ambient temperature range between

−20°C and +40°C shall require no additional ambient tem-

Change Description: Clarified the requirements for defining temperature class as referring to operating temperature when blanketed with dust. Also, removed informational text in this section. Impact(s) : No negative impact.

2



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perature marking. Electrical equipment that is designed for

use in a range of ambient temperatures other than −20°C

and +40°C is considered to be special; and the ambient

temperature range shall then be marked on the equipment,

including either the 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 temperatures exceeding

40°C (104°F) shall be marked with both the maximum am-

bient temperature and the operating temperature at that am-

bient temperature.


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


(1) Threaded rigid metal conduit or threaded steel interme-

diate 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 No. 2: Equipment identified as intrinsically safe

“iaD” or “ia” shall be permitted to be connected using the

wiring methods identified in 504.20.

Change Description: The wiring methods permitted for intrinsically safe apparatus in explosive dust atmospheres classified under the zone scheme are different from those permitted under the Division scheme. The wiring methods for intrinsically safe apparatus were previously addressed in Section 506.8 – Protection techniques. Impact(s) : No negative impact.

1



with 506.15(A), (B), or (C).



(6) Where necessary to employ flexible connections, liq-

uidtight flexible metal conduit with listed fittings, liq-

uidtight flexible nonmetallic conduit with listed fittings,

or flexible cord listed for extra-hard usage and provided

with listed fittings shall be used. Where flexible cords

Change Description: The change under subsection 506.15(A)(6) correlates the requirements with Chapter 4. Impact(s) : No negative impact.

1



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are used, they shall also comply with 506.17 and shall

be terminated with a listed cord connector that main-

tains the type of protection of the terminal compart-

ment. Where flexible connections are subject to oil or

other corrosive conditions, the insulation of the con-

ductors shall be of a type listed for the condition or

shall be protected by means of a suitable sheath.

Exception No. 2: For elevator use, an identified elevator

cable of Type EO, ETP, or ETT, shown under the “use”

column in Table 400.4 for “hazardous (classified) loca-

tions,” and terminated with listed connectors that maintain

the type of protection of the terminal compartment shall be

permitted.



with 506.15(A), (B), or (C).





installed in raceways in accordance with 506.15(A).

Optical fiber cables shall be sealed in accordance with

506.16.


2



with 506.15(A), (B), or (C).

(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.

Exception: Equipment identified as intrinsically safe “ibD” or


1



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“ib” shall be permitted to be connected using the wiring methods

identified in 504.20.



with 506.15(A), (B), or (C).

(C) Zone 22. In Zone 22 locations, the following wiring


(7) Nonincendive field wiring Intrinsic safety type of pro-

tection “ic” shall be permitted using any of the wiring

methods permitted for unclassified locations. Nonin-

cendive field wiring Intrinsic safety type of protection

“ic” systems shall be installed in accordance with the

control drawing(s). Simple Simple apparatus, not

shown on the control drawing, shall be permitted in a

nonincendive field wiring circuit, circuit of intrinsic

safety type of protection “ic”, provided that the simple

apparatus does not interconnect the nonincendive field

wiringintrinsic safety type of protection “ic” circuit to

any other circuit. Separation of nonincendive field wiring circuitscir- cuits of intrinsic safety type of protection “ic” shall be in accordance with one of the following:


1



with 506.15(A), (B), or (C).

(C) Zone 22. In Zone 22 locations, the following wiring




installed in cable trays or any raceway in accordance with

506.15(C). Optical fiber cables shall be sealed in



2

506.20 Equipment Installation.

(D) Material Group. Equipment marked Group IIIC shall

be permitted for applications requiring IIIA or IIIB equip-

ment. Similarly, equipment marked Group IIIB shall be

Change Description: This change addresses the suitability of equipment marked with the chemical formula of a specific material. Although clear in the

1



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permitted for applications requiring IIIA equipment.

product standards, it is not clear in Article 506 that IIIC equipment is suitable for applications requiring IIIA or IIIB equipment. Similarly, it is not clear that IIIB equipment is suitable for applications requiring IIIA equipment. Impact(s) : No negative impact.

506.21 Multiwire Branch Circuits. In Zone 20 and Zone

21 locations, a multiwire branch circuit shall not be permit-

ted.



simultaneously.


1

506.25 Grounding and Bonding. Regardless of the volt-

age of the electrical system, Ggrounding and bonding shall

comply with Article 250 and the requirements in 506.25(A)

and (B).


1

ARTICLE 514 Motor Fuel Dispensing Facilities

514.3 Classification of Locations. [See Figure 514.3.]

(C) Motor Fuel Dispensing Stations in Boatyards and

Marinas.

(1) General. Electrical wiring and equipment located at or

serving motor fuel dispensing locations shall be installed on

the side of the wharf, pier, or dock opposite from the liquid

piping system.

(2) Classification of Class I, Division 1 and 2 Areas. The

following criteria shall be used for the purposes of applying

Change Description: Relocated the area classification requirements from 555.21(B) into a new 514.3(C ). Area classification requirements for motor fuel dispensing are not appropriate for Section 555.21. Impact(s) : No negative impact.

1



of 203

Table 514.3(B)(1) and Table 514.3(B)(2) to motor fuel dis-

pensing equipment on floating or fixed piers, wharfs, or

docks.

(D) Closed Construction. Where the construction of float-

ing docks, piers, or wharfs is closed so that there is no

space between the bottom of the dock, pier, or wharf and

the water, as in the case of concrete-enclosed expanded

foam or similar construction, and the construction includes

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 specified in Table 514.3(B)(1) for dis-

penser and outdoor locations.

(2) Spaces below the surface of the floating dock, pier, or

wharf that have 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.

Exception No. 1: Dock, pier, or wharf sections that do not

support fuel dispensers and abut, but are located 6.0 m

(20 ft) or more from, dock sections that support a fuel

dispenser(s) shall be permitted to be Class I, Division 2

locations where documented air space is provided between

dock sections to allow flammable liquids or vapors to dis-

sipate without traveling to such dock sections. The docu-

mentation shall comply with 500.4(A).

Exception No. 2: Dock, pier, or wharf sections that do not

support fuel dispensers and do not directly abut sections

that support fuel dispensers shall be permitted to be unclas-

sified where documented air space is provided and where

flammable liquids or vapors cannot travel to such dock

sections. The documentation shall comply with 500.4(A).

(E) Open Construction. Where the

construction of piers, wharfs, or docks is open,

as in the case of decks built on stringers

supported by pilings, floats, pontoons, or similar



of 203

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 a Class 1, Division

2 location.

(2) Enclosures such as tubs, voids, pits, vaults, boxes, de-

pressions, piping chases, or similar spaces where flam-

mable liquids or vapors can accumulate within 6.0 m

(20 ft) of the dispenser shall be a Class I, Division 1

location.

ARTICLE 514 Spray Application, Dipping, Coating, and CoatingPrinting Processes Using Flammable or Combustible Materials

Flash-Off Area. An open or enclosed area after a spray

application process where vapors are released due to expo-

sure to ambient air or a heated atmosphere. [33:3.3.1.1]

Limited Finishing Workstation. An apparatus that is ca-

pable of confining the vapors, mists, residues, dusts, or

deposits that are generated by a spray application process

and that meets the requirements of Section 14.3 of

NFPA 33, Standard for Spray Application Using Flam-

mable or Combustible Materials, but does not meet the

requirements of a spray booth or spray room, as herein

defined. [33:3.3.15.1]

Resin Application Area. Any area in which polyester res-

ins or gelcoats are spray applied. [33:3.3.1.2]

Change Description: Added new definitions to Article 514 per NFPA 33. Impact(s) : No negative impact.

1

Spray Area. 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 be the maximum area in the direct path of

spray operations. In manual operations, the area limits shall

be the maximum area of spray when aimed at 180 degrees

Change Description: Revised Spray Area definition per NFPA 33. Impact(s) : No negative impact.

1



of 203

to the application surface.

Any fully enclosed, partly enclosed, or unenclosed area in

which ignitible quantities of flammable or combustible va-

pors, mists, residues, dusts, or deposits are present due to

the operation of spray processes, including (1) any area in

the direct path of a spray application process; (2) the inte-

rior of a spray booth or spray room or limited finishing

workstation, as herein defined; (3) the interior of any ex-

haust 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) any solvent concentrator

(pollution abatement) unit or solvent recovery (distillation)

unit. The following are not considered to be a 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 (pollution abatement) units.

[33:3.3.2.3]

Spray Booth. 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 a dedi-

cated air supply.

A power-ventilated enclosure for a spray application opera-

tion or process that confines and limits the escape of the

material being sprayed, including vapors, mists, dusts, and

residues that are produced by the spraying operation and

conducts or directs these materials to an exhaust system.

[33:3.3.14]

Change Description: Revised Spray Booth definition per NFPA 33. Impact(s) : No negative impact.

1

Spray Room. A power-ventilated fully enclosed room used

exclusively for open spraying of flammable or combustible

materials. A spray room is a purposefully enclosed room built

Change Description: Revised Spray Room definition per NFPA 33.

1



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for spray/coating/dipping applications provided with dedicated

ventilation supply and exhaust. Normally the room is config-

ured to house the item to be painted, providing reasonable

access around the item/process. Depending on the size of the

item being painted, such rooms may actually be the entire

building or the major portion thereof. [33:3.3.15]


Unenclosed Spray Area. Any spray area that is not con-

fined by a limited finishing workstation, spray booth, or

spray room, as herein defined. [33:3.3.2.3.2]

Change Description: Revised Unenclosed Spray Area definition per NFPA 33. Impact(s) : No negative impact.

1

516.3 Classification of Locations. Classification is based

on dangerous quantities of flammable vapors, combustible

mists, residues, dusts, or deposits that are present or might

be present in quantities sufficient to produce ignitible or

explosive mixtures with air.

(A) Zone Classification of Locations.

(1) For the purposes of this article, the zone system of

electrical area classification shall be applied as follows:

a. The inside of open or closed containers or vessels

shall be considered a Class I, Zone 0 location.

b. A Class I, Division 1 location shall be permitted to be

alternatively classified as a Class I, Zone 1 location.

c. A Class I, Division 2 location shall be permitted to be

alternatively classified as a Class I, Zone 2 location.

d. A Class II, Division 1 location shall be permitted to

be alternatively classified as a Zone 21 location.

e. A Class II, Division 2 location shall be permitted to

be alternatively classified as a Zone 22 location.

[33: 6.2.2]

(2) For the purposes of electrical area classification, the

division system and the zone system shall not be inter-

mixed for any given source of release. [33:6.2.3]

(3) In instances of areas within the same facility classified

separately, Class I, Zone 2 locations shall be permitted

Change Description: Revised to correlate this section with NFPA 33. Impact(s) : No negative impact.

1



of 203

to abut, but not overlap, Class I, Division 2 locations.

Class I, Zone 0 or Zone 1 locations shall not abut Class

I, Division 1 or Division 2 locations. [33:6.2.4]

(4) Open flames, spark-producing equipment or processes,

and equipment whose exposed surfaces exceed the auto-

ignition temperature of the material being sprayed shall

not be located in a spray area or in any surrounding area

that is classified as Division 2, Zone 2, or Zone 22.

Exception: This requirement shall not apply to drying, cur-

ing, or fusing apparatus. [33:6.2.5]

(5) Any utilization equipment or apparatus that is capable

of producing sparks or particles of hot metal and that is

located above or adjacent to either the spray area or the

urrounding Division 2, Zone 2, or Zone 22 areas shall be

of the totally enclosed type or shall be constructed to

prevent the escape of sparks or particles of hot metal.

[33: 6.2.6]






(AB) 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:

(3) The interior of any ink fountain, ink reservoir, or ink

tank

Change Description: Replaced unenforceable language and clarified the requirement. Revised to correlate this section with NFPA 34. Impact(s) : No negative impact.

2






(BC) Class Ior I, Division 1; Class I, Zone 1; Class II,

Division 1; or Zone 21 Locations. The following spaces

shall be considered Class I, Division 1, or Class I, Zone 1, or

Change Description: Replaced unenforceable language and clarified the requirement. Revised to correlate this section with NFPA 34. Impact(s) : No negative impact.

2



of 203

Class II, Division 1, or Zone 21 locations, as applicable:

(7) For limited finishing workstations, the area inside the

curtains or partitions. See Figure 516.3(D)(5).






(CD) Class Ior I, Division 2; Class I, Zone 2; Class II,

Division 2; or Zone 22 Locations. The following spaces

shall be considered Class I, Division 2, or 2; Class I,

Zone 2, or 2; Class II, Division 2; or Zone 22, as

applicable.

(1) Open Spraying.Unenclosed Spray Processes. For

openunenclosed 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. See Figure

16.3(CD)(1). [33:6.5.1]

(2) Closed-Top, Open-Face, and Open-Front Spraying.

Spray Booths and Spray Rooms. If spray application op-

erations are conducted within a closed-top, open-face, or

open-front booth or room, as shown in Figure 516.3(D)(2) ,

any electrical wiring or utilization equipment located out-

side of the booth or room but within the boundaries desig-

nated as Division 2 or Zone 2 in Figure 516.3(C)(2) 915

mm (3 ft) of any opening shall be suitable for Class I,

Division 2; Class I, Zone 2, or 2; Class II, Division 2;or

Zone 22 locations, whichever is applicable. The Class I,

Division 2; Class I, Zone 2, or 2; Class II, Division 2;or

Zone 22 locations shown in Figure 516.3(CD)(2) shall ex-

tend 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 or room, as shown in Figure 516.3(C)(2), top.

Change Description: Replaced unenforceable language and clarified the requirement. Revised to correlate this section with NFPA 33 and 34. Impact(s) : No negative impact.

2



of 203

(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 or room, 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 automatically

stopped if the exhaust ventilation system fails. [33:6.5.2.2]

Figure 516.3(D)(2) Class I, Division 2; Class I, Zone 2; Class II, Division 2; or Zone 22 Locations Adjacent to a Closed Top, Open Face, or Open Front Spray Booth or Room.

(3) Open-Top Spraying.Spray Booths. For spraying op-

erations conducted within an open top spray booth, the

space 900915 mm (3 ft) vertically above the booth and

within 900915 mm (3 ft) of other booth openings shall be

considered Class I, Division 2; Class I, Zone 2; or Class II,

Division 2; or Zone 22. [33:6.5.3]

(4) Enclosed Spray Booths and Spray Rooms. For spray-

ing operations confined to an enclosed spray booth or room,

the space within 900 mm (3 ft) in all directions from any

openings considered Class I, Division 2; or Class I, Zone 2;

or Class II, Division 2 as shown in Figure

516.3(C)(4).electrical area classification shall be as follows:

[33:6.5.4]

(5) Dip Tanks and Drain Boards — Surrounding Space.

For dip tanks and drain boards, the 914-mm (3-ft) space

surrounding the Class I, Division 1 or Class I, Zone 1

location as defined in 516.3(A)(4) and as shown in Figure

516.3(C)(5). [34:6.4.4] (6) Dip Tanks and Drain Boards — Space Above Floor.

For dip tanks and drain boards, the space 900 mm (3 ft)

above the floor and extending 6 m (20 ft) horizontally in all

directions from the Class I, Division 1 or Class I, Zone 1

location.

Exception: This space shall not be required to be considered a hazardous (classified) location where the vapor



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source area is 0.46 m2 (5 ft2) or less and where the contents of the open tank trough or container do not exceed 19 L (5 gal). In addition, the vapor concentration during operation and shutdown periods shall not exceed 25 percent of the lower flammable limit outside the Class I location specified in 516.3(B)(4). [34:6.4.4 Exception]

(1) The area within 915 mm (3 ft) of any opening shall be

classified as Class I, Division 2; Class I, Zone 2; Class

II, Division 2; or Zone 22 locations, whichever is ap-

plicable, as shown in Figure 516.3(D)(4)(1).

(2) Where exhaust air is recirculated, both of the following

shall apply:

a. The interior of any recirculation path from the sec-

ondary particulate filters up to and including the air

supply plenum shall be classified as Class I, Divi-

sion 2; Class I, Zone 2; Class II, Division 2; or Zone

22 locations, whichever is applicable.

b. The interior of fresh air supply ducts shall be

unclassified.

(3) Where exhaust air is not recirculated, the interior of

fresh air supply ducts and fresh air supply plenums

shall be unclassified.

(5) Limited Finishing Workstations. For limited finishing

workstations, the area inside the 915-mm (3-ft) space hori-

zontally and vertically beyond the volume enclosed by the

outside surface of the curtains or partitions shall be classi-

fied as Class I, Division 2; Class I, Zone 2; Class II, Divi-

sion 2; or Zone 22, as shown in Figure 516.3(D)(5).

6) Areas Adjacent to Open Dipping and Coating Pro-

cesses. Electrical wiring and electrical utilization equipment

located adjacent to open processes shall meet the re-

quirements of 516(D)(6)(1) through (4) and

Figure 516.3(D)(6)(a), Figure 516.3(D)(6)(b), Figure

516.3(D)(6)(c), Figure 516.3(D)(6)(d), or Figure

516.3(D)(6)(e), whichever is applicable. [34:6.4]

(1) Electrical wiring and electrical utilization equipment

located in any sump, pit, or below grade channel that is



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within 7620 mm (25 ft) horizontally of a vapor source, as

defined by this standard, shall be suitable for Class I,

Division 1 or Class I, Zone 1 locations. If the sump, pit, or

channel extends beyond 7620 mm (25 ft) of the vapor

source, it shall be provided with a vapor stop, or it shall

be classified as Class I, Division 1 or Class I, Zone 1 for

its entire length. [34:6.4.1]


located within 1525 mm (5 ft) of a vapor source shall be

suitable for Class I, Division 1 or Class I, Zone 1

locations. The space inside a dip tank, ink fountain, ink

reservoir, or ink tank shall be classified as Class I,

Division 1 or Class I, Zone 0, whichever is applicable.

[34:6.4.2]


located within 915 mm (3 ft) of the Class I, Division 1 or

Class I, Zone 1 location described in 516.3(D)(6)(2)

shall be suitable for Class I, Division 2 or Class I, Zone

2 locations, whichever is applicable. [34:6.4.3]

(4) The space 915 mm (3 ft) above the floor and extending

6100 mm (20 ft) horizontally in all directions from the

Class I, Division 1 or Class I, Zone 1 location de-

scribed in 6.4.3 shall be classified as Class I, Division 2

or Class I, Zone 2, and electrical wiring and electrical

utilization equipment located within this space shall be

suitable for Class I, Division 2 or Class I, Zone 2

locations, whichever is applicable. [34:6.4.4]

Exception: This space shall be permitted to be unclassified

for purposes of electrical installations if the surface area of

the vapor source does not exceed 0.5 m2 (5 ft2), the con-

tents of the dip tank, ink fountain, ink reservoir, or ink tank

do not exceed 19 L (5 gal), and the vapor concentration

during operating and shutdown periods does not exceed

25 percent of the lower flammable limit.

(D7) Enclosed Coating and Dipping Operations. Areas

adjacent to enclosed dipping and coating processes shall be



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classified in accordance with 516.3(D)(7) and Figure

516.3(D)(7). The space adjacent to an enclosed dipping or

coating process or apparatus shall be considered unclassi-

fied. [34:6.5.3]

Exception: The space within 900915 mm (3 ft) in all

directions from any opening in the enclosures shall be

classified as Class I, Division 2 or Class I, Zone 2, as

applicable. [34:6.5.2]

The interior of any enclosed dipping or coating process

or apparatus shall be a Class I, Division 1 or Class I, Zone

1 location, and electrical wiring and electrical utilization

equipment located within this space shall be suitable for

Class I, Division 1 or Class I, Zone 1 locations, whichever

is applicable. The area inside the dip tank shall be classified

as Class I, Division 1 or Class I, Zone 0, whichever is

applicable. [34:6.5.1]

516.4 Wiring and Equipment in Class I Locations.

(B) Wiring and Equipment — Vapors and Residues.

Unless specifically listed for locations containing deposits

of dangerous quantities of flammable or combustible va-

pors, mists, residues, dusts, or deposits (as applicable),

there shall be no electrical equipment in any spray area as

herein defined whereon deposits of combustible residue

may readily accumulate, except wiring in rigid metal con-

duit, intermediate metal conduit, Type MI cable, or in metal

boxes or fittings containing no taps, splices, or terminal

connections. [33:6.4.2]accumulate. All electrical wiring

shall be comply with 516.4(A).

(C) Illumination. Illumination of readily ignitible areas

through panels of glass or other transparent or translucent

material shall be permitted only if it complies with the

following:

(1) Fixed lighting units are used as the source of illumina-

tion.Luminaires, like that shown in Figure

516.4(C)(1), that are attached to the walls or ceiling of

a spray area but that are outside any classified area and

are separated from the spray area by glass panels shall

Change Description: Revised to correlate this section with NFPA 33 and 34. Impact(s) : No negative impact.

2



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be suitable for use in unclassified locations. Such fix-

[33:6.6.1]

(2) The panel effectively isolates the Class I location from

the area in which the lighting unit is located.Lumi-

naires, like that shown in Figure 516.4(C)(1), that are

attached to the walls or ceiling of a spray area; that are

separated from the spray area by glass panels and that

are located within a Class 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 ser-

viced from outside the spray area. [33:6.6.2]

(3) The lighting unit is identified for its specific location.

Luminaires, like that shown in Figure 516.4(C)(3),

that are an integral part of the walls or ceiling of a

spray area shall be permitted to be separated from the

spray area by glass panels that are an integral part of

the fixture. Such fixtures shall be 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 combus-

tible residues. Such fixtures shall be permitted to be

serviced from inside the spray area. [33:6.6.3]

(4) The panel is of a material or is protected so that break-age

is unlikely.Glass panels used to separate luminaires from

the spray area or that are an integral part of the luminaire

shall meet the following requirements.

a. Panels for light fixtures or for observation shall be

of heat-treated glass, laminated glass, wired glass,

or hammered-wired glass and shall be sealed to con-

fine vapors, mists, residues, dusts, and deposits to

the spray area. [33:5.5.1]

Exception: Listed spray booth assemblies that have vision

panels constructed of other materials shall be permitted.

(5) b. 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 radia-

tion or conduction from the source of illumination.



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Panels for light fixtures shall be separated from the

fixture to prevent the surface temperature of the

panel from exceeding 93°C (200°F). [33:5.5.2]

c. The panel frame and method of attachment shall be

designed to not fail under fire exposure before the

vision panel fails. [33:5.5.3]

(F) Static Electric Discharges.

(1) All persons and all electrically conductive objects, in-

cluding any metal parts of the process equipment or

apparatus, containers of material, exhaust ducts, and

piping systems that convey flammable or combustible

liquids, shall be electrically grounded. [34:6.8.1]

(2) Provision shall be made to dissipate static electric charges

from all nonconductive substrates in printing processes.

516.10 Special Equipment. (A) Fixed Electrostatic Equipment. This section shall ap-

ply to any equipment using electrostatically charged ele-

ments for the atomization, charging, and/or precipitation of

hazardous materials for coatings on articles or for other

similar purposes in which the charging or atomizing device

is attached to a mechanical support or manipulator. This

shall include robotic devices. This section shall not apply to

devices that are held or manipulated by hand. Where robot

or programming procedures involve manual manipulation

of the robot arm while spraying with the high voltage on,

the provisions of 516.10(B) shall apply. The installation of

electrostatic spraying equipment shall comply with

516.10(A)(1) through (A)(10). Spray equipment shall be

listed except as otherwise permitted. All automatic electro-

static equipment systems shall comply with 516.4(A)(1)

through (A)(9). [33:11.5]

(10) Other Than Nonincendive Equipment. Spray equip-

ment that cannot be classified as nonincendive shall comply

with (A)(10)(a) and (A)(10)(b).

(a) Conveyors or, hangers, and application equipment shall

be arranged so as to maintain that a safe distancemi-

nimum separation of at least twice the sparking distance is

Change Description: Revised to correlate this section with NFPA 33 and made editorial changes to clarify the language. Impact(s) : No negative impact.

2



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maintained between goods the workpiece or material being

paintedsprayed and electrodes, electrostatic atomizing

heads, or charged conductors. Warnings defining this safe

distance shall be posted. [33:11.4.1]

(B) Electrostatic Hand-Spraying Equipment. This sec-

tion shall apply to any equipment using electrostatically

charged elements for the atomization, charging, and/oror

precipitation of flammable and combustible materials for

coatings on articles, or for other similar purposes in which

the charging or atomizing device is hand-held orand ma-

nipulated during the spraying operation. Electrostatic hand-

spraying equipment and devices used in connection with

paint-spraying operations shall be of listed types and shall

comply with 516.10(B)(1) through (B)(5).

(3) Handle. The handle of the spraying gun shall be elec-

trically connected to ground by a metallic connectioncon-

ductive material and be constructed so that the operator in

normal operating position is in intimatedirect electrical

contact with the grounded handle with a resistance of not

more than 1 megohm to prevent buildup of a static charge

on the operator’s body. Signs indicating the necessity for

grounding other persons entering the spray area shall be

conspicuously posted.

(4) Electrostatic Equipment. All electrically conductive

objects in the spraying area, except those objects required

by the process to be at high voltage, shall be adequately

grounded.electrically connected to ground with a resistance

of not more than 1 megohm. This requirement shall apply

to paint containers, wash cans, and any other electrical con-

ductive objects or devices in the area. The equipment shall

carry a prominent, permanently installed warning regarding

the necessity for this grounding feature.

ARTICLE 517 Health Care Facilities

(Note: Changes to this Article in general are not applicable and are not addressed in this evaluation)

ARTICLE 520



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Theaters, Audience Areas of Motion Picture and Television Studios, Performance Areas, and Similar Locations


ARTICLE 522 Control Systems for Permanent

Amusement Attractions (Note: Changes to this Article in general are not applicable and are not addressed in this evaluation)

ARTICLE 525 Carnivals, Circuses, Fairs, and Similar Events


ARTICLE 530 Motion Picture and Television Studios, and Similar Locations

(Note: Changes to this Article in general are not applicable and are not addressed in this evaluation) ARTICLE 540

Motion Picture Projection Rooms (Note: Changes to this Article in general are not applicable and are not addressed in this evaluation)

ARTICLE 547 Agricultural Buildings


Mobile Homes, Manufactured Homes, and Mobile Home Parks 550.15 Wiring Methods and Materials. Except as spe-

cifically limited in this section, the wiring methods and

materials included in this Code shall be used in mobile

homes. Aluminum conductors, aluminum alloy conductors,

and aluminum core conductors such as copper-clad aluminum

shall not be acceptable for use as branch-circuit wiring.

(H) Under-Chassis Wiring (Exposed to Weather).

Where outdoor or under-chassis line-voltage (120 volts,

nominal, or higher) wiring is exposed to moisture or physi-

cal damage, it shall be protected by rigid metal conduit or

intermediate metal conduit, except as provided in (1) or (2).

a conduit or raceway approved for use in wet locations or

where subject to physical damage. The conductors shall be

suitablelisted for use in wet locations.

Change Description: Editorial change, clarifying requirements. Impact(s) : No negative impact.

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(1) Where closely routed against frames and equipment

enclosures, reinforced thermosetting resin conduit

(RTRC) listed for aboveground use, Type MI cable,

electrical metallic tubing, or rigid polyvinyl chloride

conduit (PVC) shall be permitted.

(2) Where extending vertically from a direct-burial depth

of at least 457 mm (18 in.) below grade and terminated

to a factory-installed conduit or enclosure, Schedule 80

PVC or RTRC listed for exposure to physical damage.

ARTICLE 551 Recreational Vehicles and Recreational Vehicle Parks


ARTICLE 552 Park Trailers


ARTICLE 553 Floating Buildings


Marinas and Boatyards (Note: Changes to this Article in general are not applicable and are not addressed in this evaluation)

ARTICLE 590 Temporary Installations

590.4 General.

(J) Support. Cable assemblies and flexible cords and

cables shall be supported in place at intervals that ensure

that they will be protected from physical damage. Support

shall be in the form of staples, cable ties, straps, or similar

type fittings installed so as not to cause damage. Cable

assemblies and flexible cords and cables installed as branch

circuits or feeders shall not be installed on the floor or on

the ground. Extension cords shall not be required to comply

with 590.4(J). Vegetation shall not be used for support of

overhead spans of branch circuits or feeders.

Change Description: Restricted temporary installation requirements by not allowing cable assemblies and flexible cords to be installed on the floor or on the ground. This restriction does not include extension cords. Impact(s) : Improves safety - no negative impact. Procedures addressing temporary wiring may need to be reviewed to ensure compliance with this new requirement.

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590.6 Ground-Fault Protection for Personnel. Ground-

fault protection for personnel for all temporary wiring in-

stallations shall be provided to comply with 590.6(A) and

(B). This section shall apply only to temporary wiring in-

stallations used to supply temporary power to equipment

used by personnel during construction, remodeling, main-

tenance, repair, or demolition of buildings, structures,

equipment, or similar activities. This section shall apply to

power derived from an electric utility company or from an

on-site-generated power source.

(A) Receptacle Outlets. Temporary receptacle installa-

tions used to supply temporary power to equipment used by

personnel during construction, remodeling, maintenance,

repair, or demolition of buildings, structures, equipment, or

similar activities shall comply with the requirements of

590.6(A)(1) through (A)(3), as applicable.

Exception: In industrial establishments only, where condi-

tions of maintenance and supervision ensure that only

qualified personnel are involved, an assured equipment

grounding conductor program as specified in 590.6(B)(2)

shall be permitted for only those receptacle outlets used to

supply equipment that would create a greater hazard if

power were interrupted or having a design that is not com-

patible with GFCI protection.

(1) Receptacle Outlets Not Part of Permanent Wiring.

All 125-volt, single-phase, 15-, 20-, and 30-ampere recep-

tacle outlets that are not a part of the permanent wiring of

the building or structure and that are in use by personnel

shall have ground-fault circuit-interrupter protection for

personnel. Listed cord sets or devices incorporating listed

ground-fault circuit-interrupter protection for personnel

identified for portable use shall be permitted.

Change Description: This change clarifies the requirement for GFI protection of personnel, allowing use of listed cord sets or devices with GFI protection, in addition to GFI protected outlets. Impact(s) : No negative impact.

2

ARTICLE 600 Electric Signs and Outline Lighting

600.6 Disconnects. Each sign and outline lighting system,

feeder circuit or branch circuit supplying a sign, outline Change Description: 2



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lighting system, or skeleton tubing shall be controlled by an

externally operable switch or circuit breaker that opens all

ungrounded conductors and controls no other load. The

switch or circuit breaker shall open all ungrounded conduc-

tors simultaneously on multi-wire branch circuits in accor-

dance with 210.4(B). Signs and outline lighting systems

located within fountains shall have the disconnect located

in accordance with 680.12.

(A) Location.

(1) At Point of Entry to a Sign Enclosure. The discon-

nect shall be located at the point the feeder circuit or branch

circuit(s) supplying a sign or outline lighting system enters

a sign enclosure or a pole in accordance with 600.5(C)(3)

and shall disconnect all wiring where it enters the enclosure

of the sign or pole.

Exception: A disconnect shall not be required for branch

or feeder circuits passing through the sign where enclosed

in a Chapter 3 listed raceway.

(12) Within Sight of the Sign. The disconnecting means

shall be within sight of the sign or outline lighting system

that it controls. Where the disconnecting means is out of

the line of sight from any section that is able to be ener-

gized, the disconnecting means shall be capable of being

locked in the open position. lockable in accordance with

110.25. The provision for locking or adding a lock to the

disconnecting means must remain in place at the switch or

circuit breaker whether the lock is installed or not. Portable

means for adding a lock to the switch or circuit breaker

shall not be permitted.

(23) Within Sight of the Controller. The following shall

apply for signs or outline lighting systems operated by elec-

tronic or electromechanical controllers located external to

the sign or outline lighting system:

(1) The disconnecting means shall be permitted to be lo-

cated within sight of the controller or in the same en-

closure with the controller.

(2) The disconnecting means shall disconnect the sign or

Added a requirement for a sign disconnecting means to be installed at the supply circuit point of entry. Removed lockable disconnecting means requirements repeated throughout the code and replaced with a reference to Section 110.25, covering these requirements generically. Editorial change, simplifying use of the NEC. Impact(s) : No negative impact.



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outline lighting system and the controller from all un-

grounded supply conductors.

(3) The disconnecting means shall be designed such that

no pole can be operated independently and shall be

capable of being locked in the open position. lockable

in accordance with 110.25.The provisions for locking

or adding a lock to the disconnecting means must re-

main in place at the switch or circuit breaker whether

the lock is installed or not. Portable means for adding a

lock to the switch or circuit breaker shall not be

permitted.

600.21 Ballasts, Transformers, Electronic Power Sup-

plies, and Electronic Class 2 Power Supplies.Sources.

Ballasts, transformers, electronic power supplies, and Class

2 power sources shall be of the self-contained type or be

enclosed by placement in a listed sign body or listed sepa-

rate enclosure.

(A) Accessibility. Ballasts, transformers, electronic power

supplies, and electronic Class 2 power suppliessources shall

be located where accessible and shall be securely fastened

in place.

(B) Location. Ballasts, transformers, electronic power sup-

plies, and electronic Class 2 power suppliessources shall be

installed as near to the lamps or neon tubing as practicable

to keep the secondary conductors as short as possible.

(C) Wet Location. Ballasts, transformers, electronic

power supplies, and electronic Class 2 power supplies

sources used in wet locations shall be of the weatherproof

type or be of the outdoor type and protected from the

weather by placement in a sign body or separate enclosure.

(D) Working Space. A working space at least 900 mm

(3 ft) high,high × 900 mm (3 ft) wide, bywide × 900 mm

(3 ft) deep shall be provided at each ballast, transformer,

electronic power supply, and electronic Class 2 power

supplysource or at its enclosure where not installed in a

sign.

Change Description: Added Class 2 power supplies which are used in LED sign, to ensure that the installation requirements are applied to these power supply sources. Impact(s) : No negative impact.

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(E) Attic and Soffit Locations. Ballasts, transformers,

electronic power supplies, and electronic Class 2 power

suppliessources shall be permitted to be located in attics

and soffits, provided there is an access door at least 900 mm

by× 562.5 mm (36 in. by× 221⁄2 in.) and a passageway of at

least 900 mm (3 ft) high by× 600 mm (2 ft) wide with a

suitable permanent walkway at least 300 mm (12 in.) wide

extending from the point of entry to each component. At

least one lighting outlet containing a switch or controlled

by a wall switch shall be installed in such spaces. At least

one point of control shall be at the usual point of entry to

these spaces. The lighting outlet shall be provided at or

near the equipment requiring servicing.

(F) Suspended Ceilings. Ballasts, transformers, electronic

power supplies, and electronic Class 2 power supplies

sources shall be permitted to be located above suspended

ceilings, provided that their enclosures are securely fas-

tened in place and not dependent on the suspended-ceiling

grid for support. Ballasts, transformers, and electronic

power supplies installed in suspended ceilings shall not be

connected to the branch circuit by flexible cord.

600.32 Neon Secondary-Circuit Wiring, over 1000

Volts, Nominal

(A) Wiring Methods. (1) Installation. Conductors shall be installed in rigid

metal conduit, intermediate metal conduit, PVC conduit,

RTRC, liquidtight flexible nonmetallic conduit, flexible

metal conduit, liquidtight flexible metal conduit, electrical

metallic tubing, metal enclosures; on insulators in metal

raceways; or in other equipment listed for use with neon

secondary circuits over 1000 volts.

Change Description: Removed PVC and RTRC conduits from the list of acceptable wiring methods for neon secondary –circuit wiring over 1000 V, which were inadvertently inserted in the 2008 version. Impact(s) : No negative impact.

1

ARTICLE 605 Office Furnishings(Consisting of Lighting

Accessories and Wired Partitions) 605.5605.6 Lighting Accessories. Lighting equipment

shall be listed and identified for use with wired partitions Change Description: Modified language of this article and added clarifications

2



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office furnishings and shall comply with 605.5(A)605.6(A),

(B), and (C).

(B) Connection. Where cord and plug connection is pro-

vided, it shall comply with all of the following:

(1) theThe cord length shall be suitable for the intended

application but shall not exceed 2.7 m (9 ft) in length.

(2) The cord shall not be smaller than 18 AWG, AWG.

(3) The cord shall contain an equipment grounding con-

ductor, andexcept as specified in 605.6(B)(4).

(4) Cords on the load side of a listed Class 2 power source

shall not be required to contain an equipment grounding

conductor.

(5) The cord shall be of the hard usage type, except as

specified in 605.6(B)(6).

(6) A cord provided on a listed Class 2 power source shall

be of the type provided with the listed luminaire assembly or

of the type specified in 725.130 and 725.127.

regarding application of Class 2 power sources in office furnishings. Impact(s) : No negative impact.

ARTICLE 610 Cranes and Hoists

610.31 Runway Conductor Disconnecting Means. A dis-

connecting means that has a continuous ampere rating not

less than that calculated in 610.14(E) and (F) shall be pro-

vided between the runway contact conductors and the

power supply. SuchThe disconnecting means shall consist

of a motor-circuit switch, circuit breaker, or molded-case

switch.comply with 430.109. This disconnecting means

shall be as follows:

(1) Readily accessible and operable from the ground or

floor level

(2) Capable of being locked in the open position. The pro-

vision for locking or adding a lock to the disconnecting

means shall be installed on or at the switch or circuit

breaker used as the disconnecting means and shall re-

main in place with or without the lock installed. Por

table means for adding a lock to the switch or circuit

breaker shall not be permitted as the means required to

Change Description: Removed lockable disconnecting means requirements repeated throughout the code and replaced with a reference to Section 110.25, covering these requirements generically. In addition, referred to 430.109 for supplemental requirements. Included exception addressing disconnecting means for electrolytic cell lines. Impact(s) : No negative impact.

2



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be installed at and remain with the equipment.Lockable

open in accordance with 110.25

Exception: The runway conductor disconnecting means

for electrolytic cell lines shall be permitted to be placed out

of view of the runway contact conductors where either of

the following conditions are met: (1) Where a location in view of the contact conductors is

impracticable or introduces additional or increased

hazards to persons or property

(2) In industrial installations, with written safety proce-

dures, where conditions of maintenance and supervi-

sion ensure that only qualified persons service the

equipment

ARTICLE 620 Elevators, Dumbwaiters, Escalators, Moving Walks, Platform Lifts, and Stairway Chairlifts

620.21 Wiring Methods. Conductors and optical fibers lo-

cated in hoistways, in escalator and moving walk wellways,

in platform lifts, stairway chairlift runways, machinery

spaces, control spaces, in or on cars, in machine rooms and

control rooms, not including the traveling cables connect-

ing the car or counterweight and hoistway wiring, shall be

installed in rigid metal conduit, intermediate metal conduit,

electrical metallic tubing, rigid nonmetallic conduit, or

wireways, or shall be Type MC, MI, or AC cable unless

otherwise permitted in 620.21(A) through (C).

Exception: Cords and cables of listed cord- and plug-

connected equipment shall not be required to be installed in

a raceway.

Change Description: Added exception for cords and cables allowing their installation without a raceway, recognizing that some equipment utilized in hoistways, moving walkways, etc. use cords for power supply (computer displays, power supplies, etc.). The wiring typically applied for this type of equipment is not meant to be installed in raceways. Impact(s) : No negative impact. Revised to correlate this section with NFPA 33 and 34.

2

620.22 Branch Circuits for Car Lighting, Receptacle(s),

Ventilation, Heating, and Air-Conditioning.

(B) Air-Conditioning and Heating Source. A dedicated-

separate branch circuit shall supply the air-conditioning and

Change Description: Editorial change clarifying language.

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heating units on each elevator car. The overcurrent device

protecting the branch circuit shall be located in the elevator

machine room or control room/machinery space or control

space.


620.41 Suspension of Traveling Cables. Traveling cables

shall be suspended at the car and hoistways’ ends, or coun-

terweight end where applicable, so as to reduce the strain

on the individual copper conductors to a minimum.

Traveling cables shall be supported by one of the fol-

lowing means:

(1) By their steel supporting member(s)

(2) By looping the cables around supports for unsupported

lengths less than 30 m (100 ft)

(3) By suspending from the supports by a means that au-

tomatically tightens around the cable when tension is

increased for unsupported lengths up to 60 m (200 ft)

Informational Note: Unsupported length for the hoist-

way suspension means is shall be that length of cable as

measured from the point of suspension in the hoistway to

the bottom of the loop, with the elevator car located at the

bottom landing. Unsupported length for the car suspension

means is shall be that length of cable as measured from the

point of suspension on the car to the bottom of the loop,

with the elevator car located at the top landing.

Change Description: Converted the text of the Informational Note to 620.41 into 620.41 as permissive language to clarify the intent of this section. Impact(s) : No negative impact.

1

620.62 Selective Coordination. Where more than one

driving machine disconnecting means is supplied by a

single feeder, the overcurrent protective devices in each

disconnecting means shall be selectively coordinated with

any other supply side overcurrent protective devices.

Selective coordination shall be selected by a licensed

professional engineer or other qualified person engaged pri-

marily in the design, installation, or maintenance of electri-

Change Description: Added a requirement to have selective coordination developed by a licensed professional engineer or other qualified person and be made available to AHJ. Impact(s) : No safety impact. May have an impact on design agencies to

2



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cal systems. The selection shall be documented and made

available to those authorized to design, install, inspect,

maintain, and operate the system.

have documentation from licensed professional engineer to meet the requirement.

ARTICLE 625 Electric Vehicle Charging System

625.4 Voltages. Unless other voltages are specified, the

nominal ac system voltages of 120, 120/240, 208Y/120,

240, 480Y/277, 480, 600Y/347, and 600 volts and dc sys-

tem voltages of up to 600 volts shall be used to supply

equipment covered by this article.

Change Description: Revised to include dc system voltage criteria for supply equipment covered by Article 625. Impact(s) : No negative impact.

2

625.17 Cable.Cords and Cables. The electric vehicle sup-

ply equipment cable shall be Type EV, EVJ, EVE, EVJE,

EVT, or EVJT flexible cable as specified in Article 400 and

Table 400.4. Ampacities shall be as specified in Table

400.5(A)(1) for 10 AWG and smaller, and in Table

400.5(A)(2) for 8 AWG and larger. The overall length of

the cable shall not exceed 7.5 m (25 ft) unless equipped

with a cable management system that is listed as suitable

for the purpose. Other cable types and assemblies listed as

being suitable for the purpose, including optional hybrid

communications, signal, and composite optical fiber cables,

shall be permitted.

(A) Power-Supply Cord. The cable for cord-connected

equipment shall comply with all of the following:

(1) Be any of the types specified in 625.17(B) or hard

service cord, junior hard service cord, or portable

power cable types in accordance with Table 400.4.

Hard service cord, junior hard service cord, or portable

power cable types shall be listed, as applicable, for

exposure to oil and damp and wet locations.

(2) Have an ampacity as specified in Table 400.5(A)(1) or,

for 8 AWG and larger, in the 60°C columns of Table

400.5(A)(2).

(3) Have an overall length as specified in 625.17(A)(3)a or

Change Description: Part of the renumbering of sections and reorganization of this article into three parts. The changes also address evolving EV technology. Impact(s) : No negative impact.

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b as follows:

a. When the interrupting device of the personnel pro-

tection system specified in 625.22 is located within

the enclosure of the supply equipment or charging

system, the power-supply cord shall be not more

than 300 mm (12 in.) long,

b. When the interrupting device of the personnel pro-

tection system specified in 625.22 is located at the

attachment plug, or within the first 300 mm (12 in.)

of the power-supply cord, the overall cord length

shall be a minimum of 1.8 m (6 ft) and shall be not

greater than 4.6 m (15 ft).

(B) Output Cable to the Electric Vehicle. The output

cable to the electric vehicle shall be Type EV, EVJ, EVE,

EVJE, EVT, or EVJT flexible cable as specified in Table

400.4.

(C) Overall Cord and Cable Length. The overall usable

length shall not exceed 7.5 m (25 ft) unless equipped with

a cable management system that is part of the listed electric

vehicle supply equipment.

(1) Not Fastened in Place. Where the electric vehicle sup-

ply equipment or charging system is not fastened in place,

the cord-exposed usable length shall be measured from the

face of the attachment plug to the face of the electric ve-

hicle connector.

(2) Fastened in Place. Where the electric vehicle supply

equipment or charging system is fastened in place, the us-

able length of the output cable shall be measured from the

cable exit of the electric vehicle supply equipment or charg-

ing system to the face of the electric vehicle connector.

625.18 Interlock. Electric vehicle supply equipment shall

be provided with an interlock that de-energizes the electric

vehicle connector and its cable whenever the electrical con-

nector is uncoupled from the electric vehicle. An interlock

shall not be required for portable cord-and-plug-connected

Change Description: Part of the renumbering of sections and reorganization of this article into three parts. The changes also address evolving EV technology.

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electric vehicle supply equipment intended for connection

to receptacle outlets rated at 125 volts, single phase, 15 and

20 amperes. An interlock shall not be required for dc sup-

plies less than 50 volts dc.


625.19 Automatic De-Energization of Cable. The elec-

tric vehicle supply equipment or the cable-connector com-

bination of the equipment shall be provided with an auto-

matic means to de-energize the cable conductors and

electric vehicle connector upon exposure to strain that

could result in either cable rupture or separation of the

cable from the electric connector and exposure of live parts.

Automatic means to de-energize the cable conductors and

electric vehicle connector shall not be required for portable

cord-and-plug-connected electric vehicle supply equipment

intended for connection to receptacle outlets rated at

125 volts, single phase, 15 and 20 amperes. An interlock

shall not be required for dc supplies less than 50 volts dc.

Change Description: This change eliminates a need for an interlock for dc supplies less than 50 V dc. Impact(s) : No negative impact.

2

625.14625.41 Rating. Electric vehicle supply equipment

shall have sufficient rating to supply the load served. For

Electric vehicle charging loads shall be considered to be

continuous loads for the purposes of this article. Where an

automatic load management system is used, the maximum

electric vehicle charging loads supply equipment load on a

service and feeder shall be considered to be continuous

loads.the maximum load permitted by the automatic load

management system.


2

625.44 Electric Vehicle Supply Equipment Connection.

Electric vehicle supply equipment shall be permitted to be

cord- and plug-connected to the premises wiring system in

accordance with one of the following:

(A) Connections to 125-Volt, Single-Phase, 15- and

20-Ampere Receptacle Outlets. Electric vehicle supply

equipment intended for connection to nonlocking, 2-pole,


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2-wire grounding-type receptacle outlets rated at 125 V,

single phase, 15 and 20 amperes or from a supply of less

than 50 volts dc.

(B) Connections to Other Receptacle Outlets. Electric

vehicle supply equipment that is rated 250 V maximum and

complying with all of the following:

(1) It is intended for connection to nonlocking, 2-pole,

3-wire and 3-pole, 4-wire, grounding-type receptacle

outlets rated not more than 50 amperes.

(2) EVSE is fastened in place to facilitate any of the fol-

lowing:

a. Ready removal for interchange

b. Facilitation of maintenance and repair

c. Repositioning of portable, movable, or EVSE fastened

in place

(3) Power-supply cord length for electric vehicle supply

equipment fastened in place is limited to 1.8 m (6 ft).

(4) Receptacles are located to avoid physical damage to the

flexible cord.

All other electric vehicle supply equipment shall be per-

manently wired and fastened in place to the supporting

surface, a wall, a pole, or other structure. The electric ve-

hicle supply equipment shall have no exposed live parts.

(A)625.50Location. The electric vehicle supply equipment

shall be located to permit for direct connection electrical

coupling of the EV connector (conductive or inductive) to

the electric vehicle. Unless specifically listed and marked

for the location, the coupling means of the electric vehicle

supply equipment shall be stored or located at a height of

not less than 450 mm (18 in.) above the floor level for

indoor locations and 600 mm (24 in.) above the grade level

for outdoor locations.

(B) Height. Unless specifically listed for the purpose and

location, the coupling means of the electric vehicle supply

equipment shall be stored or located at a height of not less

than 450 mm (18 in.) and not more than 1.2 m (4 ft) above


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the floor level.

625.52 Ventilation. The ventilation requirement for charg-

ing an electric vehicle in an indoor enclosed space shall be

determined by 625.52(A) or (B).

(DB) Ventilation Required. Where the electric vehicle

supply equipment is listed or labeled as suitable for charg-

ing electric vehicles that require ventilation for indoor

charging, and is marked in accordance with 625.15(C), me-

chanical ventilation, such as a fan, shall be provided. The

ventilation shall include both supply and exhaust equip-

ment and shall be permanently installed and located to in-

take from, and vent directly to, the outdoors. Positive-

pressure ventilation systems shall be permitted only in

vehicle charging buildings or areas that have been specifi-

cally designed and approved for that application. Mechani-

cal ventilation requirements shall be determined by one of

the methods specified in 625.29(D)625.52(B)(1) through

(DB)(4).

(4) Supply Circuits. The supply circuit to the mechanical

ventilation equipment shall be electrically interlocked with

the electric vehicle supply equipment and shall remain en-

ergized during the entire electric vehicle charging cycle.

Electric vehicle supply equipment shall be marked in ac-

cordance with 625.15. Electric vehicle supply equipment

receptacles rated at 125 volts, single phase, 15 and 20 am-

peres shall be marked in accordance with 625.15(C)625.15

and shall be switched, and the mechanical ventilation sys-

tem shall be electrically interlocked through the switch sup-

ply power to the receptacle. Electric vehicle supply equip-

ment supplied from less than 50 volts dc shall be marked in

accordance with 625.15(C) and shall be switched, and the

mechanical ventilation system shall be electrically inter-

locked through the switch supply power to the electric ve-

hicle supply


2

625.30 Outdoor Sites. Outdoor sites shall include but not

be limited to residential carports and driveways, curbside, Change Description: Part of the renumbering of sections and reorganization of this

2



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open parking structures, parking lots, and commercial

charging facilities.

(A) Location. The electric vehicle supply equipment shall

be located to permit direct connection to the electric ve-

hicle.

(B) Height. Unless specifically listed for the purpose and

location, the coupling means of electric vehicle supply

equipment shall be stored or located at a height of not less

than 600 mm (24 in.) and not more than 1.2 m (4 ft) above

the parking surface.

article into three parts. Impact(s) : No negative impact.

ARTICLE 645 Information Technology Equipment

645.4 Special Requirements for Information Technol-

ogy Equipment Room. This article shall be permitted to

provide alternate wiring methods to the provisions of Chap-

ters 1 through 4 Chapter 3 and Article 708 for power wir-

ing, 725.154Parts I and III of Article 725 for signaling

wiring, and 770.113(C) Parts I and Table 770.154(a) Vof

Article 770 for optical fiber cabling whenwhere all of the

Article 770 for optical fiber cabling whenwhere all of the

following conditions are met:

(1) Disconnecting means complying with 645.10 are pro-

vided.

(2) A separate heating/ventilating/air-conditioning (HVAC

system is provided in one of the methods identified in

645.4(2) a or b.

a. A separate HVAC system that is dedicated for infor-

mation technology equipment use and is

separated from other areas of occupancy.;or

b. Any HVAC system that serves other occupancies

and meets all of the following:

i. shall be permitted to also serve Also serves the

information technology equipment room if

ii. Provides fire/smoke dampers are provided at the

Change Description: Section rewritten for better clarity. Impact(s) : No negative impact.

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point of penetration of the room boundary.

boundary

iii. Such dampers shall operate on activation of Ac-

tivates the damper operation upon initiation by

smoke detectors anddetector alarms, by operation of

the disconnecting means required by 645.10. , or

by both

645.5 Supply Circuits and Interconnecting Cables.

(E) Under Raised Floors. Power cables, communications

cables, connecting cables, interconnecting cables, cord-and-

plug connections, and receptacles associated with the infor-

mation technology equipment shall be permitted under a

raised floor, provided the following conditions are met:

(4) Ventilation in the underfloor area is used for the infor-

mation technology equipment room only, except as

provided in 645.4(2). The ventilation system shall be so

arranged, with approved smoke detection devices, that upon

the detection of fire or products of combustion in the

underfloor space, the circulation of air will cease.

6) Cables, other than those covered in 645.5(E)(2) and (E)(3),

and those complying with (E)(6)(a) or (E)(6)(b), shall be

listed as Type DP cable having adequate fire- resistant

characteristics suitable for use under raised floors of an

information technology equipment room. are one of the

following:

a. Listed Type DP cable having adequate fire-resistant

characteristics suitable for use under raised floors of an

information technology equipment room

a. b. Interconnecting cables enclosed in a raceway

b. c. Cable type designations shown in Table 645.5

645.5(E)(6) shall be permitted. Green, or green with one or

more yellow stripes, insulated single- conductor cables, 4

AWG and larger, marked “for use in cable trays” or “for

CT use” shall be permitted for equipment grounding.

d. Equipment grounding conductors

Change Description: Section rewritten for better clarity. Impact(s) : No negative impact.

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645.14 System Grounding. Separately derived power sys-

tems shall be installed in accordance with the provisions of

Parts I and II of Article 250. Power systems derived within

listed information technology equipment that supply infor-

mation technology systems through receptacles or cable as-

semblies supplied as part of this equipment shall not be

considered separately derived for the purpose of applying

250.30

Change Description: This revision divides the grounding requirements into two different sections: one for equipment grounding and bonding, and one for system grounding. Impact(s) : No negative impact.

1

645.15 Grounding.Equipment Grounding and Bonding.

All exposed non–current-carrying metal parts of an infor-

mation technology system shall be bonded to the equipment

grounding conductor in accordance with Parts I, V, VI, VII,

and VIII of Article 250 or shall be double insulated. Power

systems derived within listed information technology

equipment that supply information technology systems

through receptacles or cable assemblies supplied as part of

this equipment shall not be considered separately derived

for the purpose of applying 250.30. Where signal reference

structures are installed, they shall be bonded to the equip-

ment grounding conductor provided for the information

technology equipment. Any auxiliary grounding elec-

trode(s) installed for information technology equipment

shall be installed in accordance with 250.54.

Change Description: This revision divides the grounding requirements into two different sections: one for equipment grounding and bonding, and one for system grounding. Impact(s) : No negative impact.

1

645.27 Selective Coordination. Critical operations data

system(s) overcurrent protective devices shall be selec-

tively coordinated with all supply-side overcurrent protec-

tive devices.

Change Description: Added a requirement for a selective coordination of overcurrent protection devices in power supply systems of critical operations data systems. Impact(s) : No negative impact.

2

ARTICLE 646 Modular Data Center



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Added a new Article. The text of this new article not included for brevity.

Change Description: Added a new article addressing requirements for modular data centers. Impact(s) : No negative impact.

2

ARTICLE 650 Pipe Organs


ARTICLE 650 Pipe Organs


ARTICLE 675 Electrically Driven or Controlled Irrigation Machines


Swimming Pools, Fountains, and Similar Installations (Note: Changes to this Article in general are not applicable and are not addressed in this evaluation)

ARTICLE 690 Solar Photovoltaic (PV) Systems

690.4 Installation.General Requirements. A) Photovoltaic Systems. Photovoltaic systems shall be

permitted to supply a building or other structure in addition

to any other electricityelectrical supply system(s).

(B) Identification and Grouping. Photovoltaic source cir-

cuits and PV output circuits shall not be contained in the

same raceway, cable tray, cable, outlet box, junction box, or

similar fitting as conductors, feeders, or branch circuits of

other non-PV systems, unless the conductors of the differ-

ent systems are separated by a partition. Photovoltaic sys-

tem conductors shall be identified and grouped as required

by 690.4(B)(1) through (4). The means of identification

shall be permitted by separate color coding, marking tape,

tagging, or other approved means.

(1) Photovoltaic Source Circuits. Photovoltaic source cir-

cuits shall be identified at all points of termination, connec-

tion, and splices.

Change Description: Article 690 was rearranged in this edition of the code. Portions of Section 690.4 were moved to Section 690.31. Also, added a subsection requiring that the personnel installing PV systems shall be qualified. Impact(s) : No negative impact.

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(2) Photovoltaic Output and Inverter Circuits. The con-

ductors of PV output circuits and inverter input and output

circuits shall be identified at all points of termination, con-

nection, and splices.

(3) Conductors of Multiple Systems. Where the conduc-

tors of more than one PV system occupy the same junction

box, raceway, or equipment, the conductors of each system

shall be identified at all termination, connection, and splice

points.

Exception: Where the identification of the conductors is

evident by spacing or arrangement, further identification is

not required.

(4) Grouping. Where the conductors of more than one PV

system occupy the same junction box or raceway with a

removable cover(s), the ac and dc conductors of each sys-

tem shall be grouped separately by wire ties or similar

means at least once, and then shall be grouped at intervals

not to exceed 1.8 m (6 ft).

Exception: The requirement for grouping shall not apply if

the circuit enters from a cable or raceway unique to the

circuit that makes the grouping obvious.

(C) Module Connection Arrangement. The connection to

a module or panel shall be arranged so that removal of a

module or panel from a photovoltaic source circuit does not

interrupt a grounded conductor to other PV source circuits.

(DB) Equipment. Inverters, motor generators, photovolta-

icPV modules, photovoltaicPV panels, ac photovoltaicPV

modules, source-circuitdc combiners, dc-to-dc converters,

and charge controllers intended for use in photovoltaicPV

power systems shall be identified and listed for the PV

application. (E) Wiring and Connections. The equipment and systems

in 690.4(A) through (D) and all associated wiring and in-

terconnections shall be installed only by qualified persons.

Informational Note: See Article 100 for the definition of qualified person.



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(F) Circuit Routing. Photovoltaic source and PV output

conductors, in and out of conduit, and inside of a building

or structure, shall be routed along building structural mem-

bers such as beams, rafters, trusses, and columns where the

location of those structural members can be determined by

observation. Where circuits are imbedded in built-up, lami-

nate, or membrane roofing materials in roof areas not cov-

ered by PV modules and associated equipment, the location

of circuits shall be clearly marked.

(G) Bipolar Photovoltaic Systems. Where the sum, with-

out consideration of polarity, of the PV system voltages of

the two monopole subarrays exceeds the rating of the con-

ductors and connected equipment, monopole subarrays in a

bipolar PV system shall be physically separated, and the

electrical output circuits from each monopole subarray

shall be installed in separate raceways until connected to

the inverter. The disconnecting means and overcurrent pro-

tective devices for each monopole subarray output shall be

in separate enclosures. All conductors from each separate

monopole subarray shall be routed in the same raceway.

Exception: Listed switchgear rated for the maximum volt-

age between circuits and containing a physical barrier

separating the disconnecting means for each monopole

subarray shall be permitted to be used instead of discon-

necting means in separate enclosures.

(C) Qualified Personnel. The installation of equipment

and all associated wiring and interconnections shall be per-

formed only by qualified persons.

690.5 Ground-Fault Protection. Grounded dc photovolta-

icPV arrays shall be provided with dc ground-fault protec-

tion meeting the requirements of 690.5(A) through (C) to

reduce fire hazards. Ungrounded dc photovoltaicPV arrays

shall comply with 690.35.

Change Description: Exception 2 was deleted because research and actual fires due to ground faults indicated that oversizing the equipment-grounding conductors in lieu of providing a ground fault protection

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Exception No. 2: Photovoltaic arrays installed at other

than dwelling units shall be permitted without ground-fault

protection if each equipment grounding conductor is sized

in accordance with 690.45.

(A) Ground-Fault Detection and Interruption. The

ground fault protection device or system shall:

1) beBe capable of detecting a ground-fault current,

ground fault in the PV array dc current-carrying con-

ductors and components, including any intentionally

grounded conductors,

(2) interruptingInterrupt the flow of fault current, and cur-

rent

(3) providingProvide an indication of the fault.fault, and

(4) Be listed for providing PV ground-fault protection

Automatically opening the grounded conductor of the

faulted circuitfor measurement purposes or to interrupt the

ground-fault current path shall be permitted. If a grounded

conductor is opened to interrupt the ground-fault current

path, all conductors of the faulted circuit shall be automati-

cally and simultaneously opened.

Manual operation of the main PV dc disconnect shall not

activate the ground-fault protection device or result in

grounded conductors becoming ungrounded.

would not reduce the potential for fire. Also, expanded the text to better define ground-fault detection requirements. Impact(s) : No negative impact.

690.6 Alternating-Current (ac) Modules.

(D) Ground-Fault Detection. Alternating-current module

systems shall be permitted to use a single detection device

to detect only ac ground faults and to disable the array by

removing ac power to the ac module(s).

Change Description: The text was deleted because there is no readily available equipment that can perform this function. There are no exposed receptacles connected to this system and ground fault detection is not necessary. Impact(s) : No negative impact.

2

690.8 Circuit Sizing and Current. (A) Calculation of Maximum Circuit Current. The

maximum current for the specific circuit shall be calculated in

accordance with 690.8(A)(1) through (A)(45). (5) DC-to-DC Converter Output Current. The maxi-

Change Description: Reworded and reorganized section to better define the requirements and to clarify expectations.

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mum current shall be the dc-to-dc converter continuous

output current rating.

(B) Ampacity and Overcurrent Device Ratings.Conduc-

tor Ampacity. PhotovoltaicPV system currents shall be

considered to be continuous.(2) Conductor Ampacity. Cir-

cuit conductors shall be sized to carry not less than the

larger of 690.8(B)(2)(a)690.8(B)(1) or (2)(b). (2).

(1) Overcurrent Devices. Overcurrent devices, where re-

quired, shall be rated as required by 690.8(B)(1)(a) through (1)(d).

(a) To carry not less than 125 percent of the maximum

currents calculated in 690.8(A).

(a)(1) One hundred and twenty-five percent of the maxi-

mum currents calculated in 690.8(A) without any additional

correction factors for conditions of use. before the applica-

tion of adjustment and correction factors.

(b) Terminal temperature limits shall be in accordance with

110.3(B) and 110.14(C).

(c) Where operated at temperatures greater than 40°C

(104°F), the manufacturer’s temperature correction factors

shall apply.

(d) The rating or setting of overcurrent devices shall be

permitted in accordance with 240.4(B), (C), and (D).

b)(2) The maximum currents calculated in 690.8(A) after

conditions of use have been applied.application of adjust-

ment and correction factors.

(c) The conductor selected, after application of condi-

tions of use, shall be protected by the overcurrent protective

device, where required.


690.9 Overcurrent Protection. (A) Circuits and Equipment. PhotovoltaicPV source cir-

cuit, photovoltaicPV output circuit, inverter output circuit,

and storage battery circuit conductors and equipment shall

be protected in accordance with the requirements of Article

240. Protection devices for PV source circuits and PV out-

put circuits shall be in accordance with the requirements of

690.9(B) through (E). Circuits, either ac or dc, connected to

Change Description: This section was revised for clarity. Also, language was added to insure that listed equipment be used to provide overcurrent protection. Impact(s) : No negative impact.

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more than one electrical source shall have overcurrent de-

vices located so as current-limited supplies (e.g., PV mod-

ules ac output of utility-interactive inverters) and also con-

nected to provide overcurrent protection from all

sources.sources having significantly higher current avail-

ability (e.g., parallel strings of modules, utility power),

shall be protected at the source from overcurrent.

B) Overcurrent Device Ratings. Overcurrent device rat-

ings shall be not less than 125 percent of the maximum

currents calculated in 690.8(A).

Exception: Circuits containing an assembly, together with

its overcurrent device(s), that is listed for continuous op-

eration at 100 percent of its rating shall be permitted to be

used at 100 percent of its rating.

CD) Photovoltaic Source and Output Circuits. Branch-

circuit or supplementary-type Listed PV overcurrent de-

vices shall be permittedrequired to provide overcurrent pro-

tection in photovoltaicPV source and output circuits. The

overcurrent devices shall be accessible but shall not be

required to be readily accessible.

Standard values of supplementary overcurrent devices

allowed by this section shall be in one ampere size incre-

ments, starting at one ampere up to and including 15 am-

peres. Higher standard values above 15 amperes for supple-

mentary overcurrent devices shall be based on the standard

sizes provided in 240.6(A).

E) Series Overcurrent Protection. In grounded PV

source circuits, a single overcurrent protection device,

where required, shall be permitted to protect the PV mod-

ules and the interconnecting conductors. In ungrounded PV

source circuits complying with 690.35, an overcurrent pro-

tection device, where required, shall be installed in each

ungrounded circuit conductor and shall be permitted to pro-

tect the PV modules and the interconnecting cables.

690.11 Arc-Fault Circuit Protection (Direct Current).

Photovoltaic systems with dc source circuits, dc output cir-

cuits, or both, on or penetrating a building operating at a

Change Description: This section was revised for clarity. Also, prescriptive methods were removed, thereby allowing alternate methods.

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PV system maximum system voltage of 80 volts or greater,

shall be protected by a listed (dc) arc-fault circuit inter-

rupter, PV type, or other system components listed to pro-

vide equivalent protection. The PV arc-fault protection

means shall comply with the following requirements:

(1) The system shall detect and interrupt arcing faults re-

sulting from a failure in the intended continuity of a

conductor, connection, module, or other system component

in the dc PV source and dc PV output circuits.

2) The system shall disable or disconnect one of the fol-

lowing:

a. Inverters or charge controllers connected to the fault circuit

when the fault is detected

b. System components within the arcing circuit


690.12 Rapid Shutdown of PV Systems on Buildings.

PV system circuits installed on or in buildings shall include

a rapid shutdown function that controls specific conductors

in accordance with 690.12(1) through (5) as follows.

(1) Requirements for controlled conductors shall apply

only to PV system conductors of more than 1.5 m (5 ft) in

length inside a building, or more than 3 m (10 ft) from a

PV array.

(2) Controlled conductors shall be limited to not more than

30 volts and 240 volt-amperes within 10 seconds of

rapid shutdown initiation.

(3) Voltage and power shall be measured between any two

conductors and between any conductor and ground.

(4) The rapid shutdown initiation methods shall be labeled

in accordance with 690.56(B).

(5) Equipment that performs the rapid shutdown shall be

listed and identified.

Change Description: This new section requires that PV systems installed on building roofs should be equipped with rapid shutdown equipment, de-energizing specific conductors of the system within 10 seconds of rapid shutdown initiation to minimize hazards to firefighters. Impact(s) : Improves safety - no negative impact

2

690.13 All Conductors.Building or Other Structure

Supplied by a Photovoltaic System. Means shall be pro-

vided to disconnect all current-carryingungrounded dc con-

ductors of a photovoltaicPV system from all other conduc-

Change Description: Section 690.13 was reorganized and rewritten to address various wiring methods previously covered in 690.4 and 690.14 and to improve clarity. Also, moved disconnect construction

1



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tors in a building or other structure. A switch, circuit breaker,

or other device shall not be installed in a grounded conductor

if operation of that switch, circuit breaker, or other device

leaves the marked, grounded conductor in an ungrounded and

energized state.

Exception No. 1: A switch or circuit breaker that is part of a

ground-fault detection system required by 690.5, or that is

part of an arc-fault detection/interruption system required

by 690.11, shall be permitted to open the grounded

conductor when that switch or circuit breaker is automati-

cally opened as a normal function of the device in respond-

ing to ground faults.

Exception No. 2: A disconnecting switch shall be permit-

ted in a grounded conductor if all of the following condi-

tions are met:

(1) The switch is used only for PV array maintenance.

(2) The switch is accessible only by qualified persons.

(3) The switch is rated for the maximum dc voltage and

current that could be present during any operation,

including ground-fault conditions.

690.14 Additional Provisions. Photovoltaic disconnecting

means shall comply with 690.14(A) through (D).

(A) Disconnecting Means. The disconnecting means shall

not be required to be suitable as service equipment and


(B) Equipment. Equipment such as photovoltaic source

circuit isolating switches, overcurrent devices, and blocking

diodes shall be permitted on the photovoltaic side of the

photovoltaic disconnecting means.

(C) Requirements for Disconnecting Means. Means

shall be provided to disconnect all conductors in a building

or other structure from the photovoltaic system conductors.

(3C) Suitable for Use. Each photovoltaicPV system dis-

connecting means shall not be suitable for the prevailing

requirements to Section 690.17. Impact(s) : No negative impact.



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conditions. required to be suitable as service equipment.

Equipment installed in hazardous (classified) locations shall

comply with the requirements of Articles 500 through 517.

690.15 Disconnection of Photovoltaic Equipment.

Means shall be provided to disconnect equipment, such as

inverters, batteries, charge controllers, and the like,charge

controllers, from all ungrounded conductors of all sources.

If the equipment is energized from more than one source,

the disconnecting means shall be grouped and identified.

A single disconnecting means in accordance with

690.17 shall be permitted for the combined ac output of one

or more inverters or ac modules in an interactive system.

(B) Equipment. Equipment such as PV source circuit iso-

lating switches, overcurrent devices, dc-to-dc converters,

and blocking diodes shall be permitted on the PV side of

the PV disconnecting means.

(C) Direct-Current Combiner Disconnects. The dc out-

put of dc combiners mounted on roofs of dwellings or other

buildings shall have a load break disconnecting means lo-

cated in the combiner or w i th in 1.8 m (6 ft) of the

combiner. The disconnecting means shall be permitted to

be remotely controlled but shall be manually operable

locally when control power is not available.

Change Description: Part of series of changes, reorganizing Article 690 and adding disconnect requirements, aimed at improving firefighters safety in case of an emergency. Impact(s) : No negative impact.

2

690.17 Switch or Circuit Breaker.Disconnect Type.

(A) Manually Operable. The disconnecting means for un-

grounded PV conductors shall consist of a manually oper-

able switch(es) or circuit breaker(s) breaker(s). The discon-

necting means shall be permitted to be power operable with

provisions for manual operation in the event of a power-

supply failure. complying with all of the following require-

ments: The disconnecting means shall be one of the follow-

ing listed devices:

(1) Located where readily accessibleA PV industrial con-

trol switch marked for use in PV systems

(2) Externally operable without exposing the operator to

Change Description: Part of series of changes, reorganizing Article 690 and including disconnect requirements, previously covered in other sections of this article. Impact(s) : No negative impact.

1



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contact with live partsA PV molded-case circuit

breaker marked for use in PV systems

(3) Plainly indicating whether in the open or closed posi-

tionA PV molded-case switch marked for use in PV

systems

(4) Having an interrupting rating sufficient for the nomi-

nal circuit voltage and the current that is available at

the line terminals of the equipmentA PV enclosed

switch marked for use in PV systems

(5) A PV open-type switch marked for use in PV systems

(6) A dc-rated molded-case circuit breaker suitable for

backfeed operation

(7) A dc-rated molded-case switch suitable for backfeed

operation

(8) A dc-rated enclosed switch

(9) A dc-rated open-type switch

(10) A dc-rated rated low-voltage power circuit breaker

Where all terminals of the disconnecting means may be

energized in the open position, a warning sign shall be

ounted on or adjacent to the disconnecting means. The

sign shall be clearly legible and have the following words

or equivalent:

(B) Simultaneous Opening of Poles. The PV disconnect-

ing means shall simultaneously disconnect all ungrounded

supply conductors.

C) Externally Operable and Indicating. The PV discon-

necting means shall be externally operable without expos-

ing the operator to contact with live parts and shall indicate

whether in the open or closed position.

(D) Disconnection of Grounded Conductor. A switch,

circuit breaker, or other device shall not be installed in a

grounded conductor if operation of that switch, circuit

breaker, or other device leaves the marked, grounded con-

ductor in an ungrounded and energized state.

Exception No. 1: A switch or circuit breaker that is part of

a ground-fault detection system required by 690.5, or that



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is part of an arc-fault detection/interruption system re-

quired by 690.11, shall be permitted to open the grounded

conductor when that switch or circuit breaker is automati-

cally opened as a normal function of the device in respond-

ing to ground faults.

Exception No. 2: A disconnecting switch shall be permit-

ted in a grounded conductor if all of the following condi-

tions are met:

(1) The switch is used only for PV array maintenance.

(2) The switch is accessible only by qualified persons.

(3) The switch is rated for the maximum dc voltage and

current that could be present during any operation,

including ground-fault conditions.

(E) Interrupting Rating. The building or structure dis-

connecting means shall have an interrupting rating suffi-

cient for the maximum circuit voltage and current that is

available at the line terminals of the equipment. Where all

terminals of the disconnecting means may be energized in

the open position, a warning sign shall be mounted on or

adjacent to the disconnecting means. The sign shall be

clearly legible and have the following words or equivalent:

WARNING ELECTRIC

SHOCK HAZARD DO NOT

TOUCH TERMINALS.

TERMINALS ON BOTH THE

LINE

AND LOAD SIDES MAY BE ENERGIZED IN

THE OPEN POSITION.

The warning sign(s) or label(s) shall comply with

110.21(B).

Exception: A connector shall be permitted to be used as

an ac or a dc disconnecting means, provided that it com-

plies with the requirements of 690.33 and is listed and

identified for the use with specific equipment.



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690.31 Methods Permitted.

(A) Wiring Systems. All raceway and cable wiring meth-

ods included in this Code and , other wiring systems and

fittings specifically intended and identified listed for use on

photovoltaic arraysPV arrays, and wiring as part of a listed

system shall be permitted. Where wiring devices with inte-

gral enclosures are used, sufficient length of cable shall be

provided to facilitate replacement.

Where photovoltaicPV source and output circuits oper-

ating at maximum system voltages greater than 30 volts are

installed in readily accessible locations, circuit conductors

shall be guarded or installed in a raceway.

B) Identification and Grouping. PV source circuits and

PV output circuits shall not be contained in the same race-

way, cable tray, cable, outlet box, junction box, or similar

fitting as conductors, feeders, branch circuits of other

non-PV systems, or inverter output circuits, unless the con-

ductors of the different systems are separated by a partition.

PV system conductors shall be identified and grouped as

required by 690.31(B)(1) through (4). The means of iden-

tification shall be permitted by separate color coding, mark-

ing tape, tagging, or other approved means.

(1) PV Source Circuits. PV source circuits shall be iden-

tified at all points of termination, connection, and splices.

(2) PV Output and Inverter Circuits. The conductors of

PV output circuits and inverter input and output circuits

shall be identified at all points of termination, connection,

and splices.

3) Conductors of Multiple Systems. Where the conduc-

tors of more than one PV system occupy the same junction

box, raceway, or equipment, the conductors of each system

shall be identified at all termination, connection, and splice

points.

Exception: Where the identification of the conductors is

evident by spacing or arrangement, further identification shall

not be required.

Change Description: Part of series of changes, reorganizing Article 690 and addressing various wiring methods, previously covered in other sections of this article. Impact(s) : No negative impact.

1



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(4) Grouping. Where the conductors of more than one PV

system occupy the same junction box or raceway with a

removable cover(s), the ac and dc conductors of each sys-

tem shall be grouped separately by cable ties or similar

means at least once and shall then be grouped at intervals

not to exceed 1.8 m (6 ft).

Exception: The requirement for grouping shall not apply if the

circuit enters from a cable or raceway unique to the circuit

that makes the grouping obvious.


(BC) Single-Conductor Cable.

(2) Cable Tray. PV source circuits and PV output circuits

using single-conductor cable listed and labeled as pho-

tovoltaic (PV) wire of all sizes, with or without a cable tray

marking/rating, shall be permitted in cable trays installed in

outdoor locations, provided that the cables are supported

at intervals not to exceed 300 mm (12 in.) and

secured at intervals not to exceed 1.4 m (4.5 ft).


1


(D) Multiconductor Cable. Multiconductor cable Type

TC-ER or Type USE-2 shall be permitted in outdoor loca-

tions in PV inverter output circuits where used with utility-

interactive inverters mounted in locations that are not

readily accessible. The cable shall be secured at intervals

not exceeding 1.8 m (6 ft). Equipment grounding for the

utilization equipment shall be provided by an equipment

grounding conductor within the cable.


1


(EG) Direct-Current Photovoltaic Source and Direct-

Current Output Circuits on or Inside a Building. Where

dc photovoltaicPV source or dc PV output circuits from a

building-integrated systems or other photovoltaic sys-

temPV systems are run inside a building or structure, they

shall be contained in metal raceways, Type MC metal-clad

Change Description: Part of series of changes, reorganizing Article 690 and addressing various wiring methods, previously covered in other sections of this article. Impact(s) :

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cable that complies with 250.118(10), or metal enclosures

from the point of penetration of the surface of the building

or structure to the first readily accessible disconnecting

means. The disconnecting means shall comply with

690.14(A)690.13(B), (B), and (C) and (D). 690.15(A) and

(B). The wiring methods shall comply with the additional

installation requirements in 690.31(G)(1) through (4).

(1) Beneath Roofs.Embedded in Building Surfaces. Wir-

ing methods shall not be installed within 25 cm (10 in.) of

the roof decking or sheathing except where directly below

the Where circuits are embedded in built-up, laminate, or

membrane roofing materials in roof surface areas not cov-

ered by PV modules and associated equipment., the loca-

tion of circuits Circuits shall be run perpendicular to the

roof penetration point to supports a minimum of 25 cm

(10 in.) below the roof decking.clearly marked using a

marking protocol that is approved as being suitable for

continuous exposure to sunlight and weather.

(4) Marking and Labeling Methods and Locations. The

labels or markings shall be visible after installation. The

labels shall be reflective, and all letters shall be capitalized

and shall be a minimum height of 9.5 mm (3⁄8 in.) in white

on a red background. Photovoltaic PV power circuit labels

shall appear on every section of the wiring system that is

separated by enclosures, walls, partitions, ceilings, or

floors. Spacing between labels or markings, or between a

label and a marking, shall not be more than 3 m (10 ft).

Labels required by this section shall be suitable for the

environment where they are installed.

No negative impact.


(I) Bipolar Photovoltaic Systems. Where the sum, with-

out consideration of polarity, of the PV system voltages of

the two monopole subarrays exceeds the rating of the con-

ductors and connected equipment, monopole subarrays in a

bipolar PV system shall be physically separated, and the

electrical output circuits from each monopole subarray

shall be installed in separate raceways until connected to


1



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the inverter. The disconnecting means and overcurrent pro-

tective devices for each monopole subarray output shall be

in separate enclosures. All conductors from each separate

monopole subarray shall be routed in the same raceway.

Bipolar PV systems shall be clearly marked with a perma-

nent, legible warning notice indicating that the disconnec-

Exception: Listed switchgear rated for the maximum volt-

age between circuits and containing a physical barrier

separating the disconnecting means for each monopole

subarray shall be permitted to be used instead of discon-

necting means in separate enclosures.


(J) Module Connection Arrangement. The connection to

a module or panel shall be arranged so that removal of a

module or panel from a PV source circuit does not interrupt

a grounded conductor connection to other PV source cir-

cuits.


1

690.35 Ungrounded Photovoltaic Power Systems. Pho-

tovoltaic power systems shall be permitted to operate with

ungrounded photovoltaicPV source and output circuits

where the system complies with 690.35(A) through (G).

(C) Ground-Fault Protection. All photovoltaicPV source

and output circuits shall be provided with a ground-fault

protection device or system that complies with 690.35(1)

through (3):(4):

(1) Detects a ground fault.fault(s) in the PV array dc

current-carrying conductors and components

(2) Indicates that a ground fault has occurred

(3) Automatically disconnects all conductors or causes the

inverter or charge controller connected to the faulted circuit to

automatically cease supplying power to output circuits.

(4) Is listed for providing PV ground-fault protection

Change Description: This change provides clarification regarding ground-fault protection devices installed in the ungrounded PV systems. Impact(s) : No negative impact.

2



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690.35 Ungrounded Photovoltaic Power Systems. Pho-

tovoltaic power systems shall be permitted to operate with

ungrounded photovoltaicPV source and output circuits

where the system complies with 690.35(A) through (G).

(D) Conductors. The photovoltaicPV source conductors

shall consist of the following: (1) Nonmetallic Metallic or nonmetallic jacketed multicon-

ductor cables

(2) Conductors installed in raceways, orraceways

(3) Conductors listed and identified as Photovoltaic (PV)

Wire PV wire installed as exposed, single conductors., or

(4) Conductors that are direct-buried and identified for

direct-burial use

Change Description: This change provides clarification regarding ground-fault protection devices installed in the ungrounded PV systems. Impact(s) : No negative impact.

2

690.41 System Grounding. For a photovoltaic power

source, one conductor of a 2-wire system with a photovol-

taic system voltage over 50 volts and the reference (center

tap) conductor of a bipolar system shall be solidly

grounded or shall use other methods that accomplish

equivalent system protection in accordance with 250.4(A)

and that utilize equipment listed and identified for the use.

Exception: Systems complying with 690.35.

Photovoltaic systems shall comply with one of the

following:

(1) Ungrounded systems shall comply with 690.35.

(2) Grounded two-wire systems shall have one conductor

grounded or be impedance grounded, and the system


(3) Grounded bipolar systems shall have the reference

(center tap) conductor grounded or be impedance

grounded, and the system shall comply with 690.5.

(4) Other methods that accomplish equivalent system pro-

tection in accordance with 250.4(A) with equipment

listed and identified for the use shall be permitted to be

used.

Change Description: Section revised for clarity into a list format. Also, removed reference to “over 50 volts” since the section now covers all voltage levels of PV systems. Impact(s) : No negative impact.

2

690.45 Size of Equipment Grounding Conductors. Change Description: 1



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Equipment grounding conductors for photovoltaicPV

source and photovoltaicPV output circuits shall be sized in

accordance with 690.45(A)250.122 or (B).. Where no over-

current protective device is used in the circuit, an assumed

overcurrent device rated at the PV maximum circuit current

shall be used when applying Table 250.122. Increases in

equipment grounding conductor size to address voltage

drop considerations shall not be required. An equipment

grounding conductor shall not be smaller than 14 AWG.

A) General. Equipment grounding conductors in photo-

voltaic source and photovoltaic output circuits shall be

sized in accordance with Table 250.122. Where no overcur-

rent protective device is used in the circuit, an assumed

overcurrent device rated at the photovoltaic rated short-

circuit current shall be used in Table 250.122. Increases in

equipment grounding conductor size to address voltage

drop considerations shall not be required. The equipment

grounding conductors shall be no smaller than 14 AWG.

(B) Ground-Fault Protection Not Provided. For other

than dwelling units where ground-fault protection is not

provided in accordance with 690.5(A) through (C), each

equipment grounding conductor shall have an ampacity of

at least two (2) times the temperature and conduit fill cor-

rected circuit conductor ampacity.

Revised section to move text from a subsection to the main body and removed portions no longer valid as a result of changes to other sections in this article. Impact(s) : No negative impact.

690.46 Array Equipment Grounding Conductors.

Equipment grounding conductors for photovoltaic mod-

ulesFor PV modules, equipment grounding conductors

smaller than 6 AWG shall comply with 250.120(C).

Where installed in raceways, equipment grounding con-

ductors and grounding electrode conductors not larger than

6 AWG shall be permitted to be solid.

Change Description: This change addresses a concern related to migration of water in strands of a conductor and subsequent degradation of the conductor and connections of conductors smaller than #6 AWG. Impact(s) : No negative impact.

2

690.47 Grounding Electrode System.

(B) Direct-Current Systems. If installing a dc system, a

grounding electrode system shall be provided in accordance

with 250.166 for grounded systems or 250.169 for un-

Change Description: This added text addresses equipment grounding requirements in ungrounded PV arrays connected to utility-interactive inverters,

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grounded systems. The grounding electrode conductor shall

be installed in accordance with 250.64.

A common dc grounding-electrode conductor shall be

permitted to serve multiple inverters. The size of the com-

mon grounding electrode and the tap conductors shall be in

accordance with 250.166. The tap conductors shall be con-

nected to the common grounding-electrode conductor by

exothermic welding or with connectors listed as grounding

and bonding equipment in such a manner that the common

grounding electrode conductor remains without a splice or

joint.

An ac equipment grounding system shall be permitted to

be used for equipment grounding of inverters and other

equipment and for the ground-fault detection reference for

ungrounded PV systems.

as allowed by 690.35. Impact(s) : No negative impact.


(C) Systems with Alternating-Current and Direct-

Current Grounding Requirements. Photovoltaic systems

having dc circuits and ac circuits with no direct connection

between the dc grounded conductor and ac grounded con-

ductor shall have a dc grounding system. The dc grounding

system shall be bonded to the ac grounding system by one

of the methods in (1), (2), or (3).

This section shall not apply to ac PV modules.

When using the methods of (C)(2) or (C)(3), the existing ac

grounding electrode system shall meet the applicable

requirements of Article 250, Part III.

(3) Combined Direct-Current Grounding Electrode

Conductor and Alternating-Current Equipment

Grounding Conductor. An unspliced, or irreversibly

spliced, combined grounding conductor shall be run from

the marked dc grounding electrode conductor connection

point along with the ac circuit conductors to the grounding

busbar in the associated ac equipment. This combined

grounding conductor shall be the larger of the sizes speci-

fied by 250.122 or 250.166 and shall be installed in accor-

dance with 250.64(E). For ungrounded systems, this con-

Change Description: Added wording addresses equipment grounding requirements in ungrounded PV systems. Impact(s) : No negative impact.

2



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ductor shall be sized in accordance with 250.122 and shall

not be required to be larger than the largest ungrounded

phase conductor.


(D) Additional Auxiliary Electrodes for Array Ground-

ing. A grounding electrode shall be installed in accordance

with 250.52 and 250.54 at the location of all ground- and

pole-mounted PV arrays and as close as practicable to the

location of roof-mounted PV arrays. The electrodes shall be

connected directly to the array frame(s) or structure. The dc

grounding electrode conductor shall be sized according to

250.166. Additional electrodes are not permitted to be used

as a substitute for equipment bonding or equipment ground-

ing conductor requirements. The structure of a ground- or

pole-mounted PV array shall be permitted to be considered

a grounding electrode if it meets the requirements of

250.52. Roof-mounted PV arrays shall be permitted to use

the metal frame of a building or structure if the require-

ments of 250.52(A)(2) are met.

Exception No. 1: An array grounding electrode(s) shall

not be required where the load served by the array is inte-

gral with the array.

Exception No. 2: An additional array grounding elec-

trode(s) shall not be required if located within 1.8 m (6 ft)

of the premises wiring electrode.

Change Description: Re-inserted subsection 690.47(D), inadvertently removed from the code in 2011. Impact(s) : No negative impact.

2

690.53 Direct-Current Photovoltaic Power Source. A

permanent label for the direct-current photovoltaicPV

power source indicating items the information specified in

(1) through (5) shall be provided by the installer at the

photovoltaicPV disconnecting means:

(1) Rated maximum power-point current.

(2) Rated maximum power-point voltage.

(3) Maximum system voltage.

(4) Short-circuit current Maximum circuit current. Where

the PV power source has multiple outputs, 690.53(1) and

(4) shall be specified for each output.

Change Description: Clarified the expectations regarding labeling of PV power sources and removed a conflict in terminology between “maximum circuit current” and “short-circuit current”, as they are used in other sections of this article. Impact(s) : No negative impact.

2



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690.56 Identification of Power Sources.

(C) Facilities with Rapid Shutdown. Buildings or struc-

tures with both utility service and a PV system, complying

with 690.12, shall have a permanent plaque or directory

including the following wording:

PHOTOVOLTAIC SYSTEM EQUIPPED

WITH RAPID SHUTDOWN

The plaque or directory shall be reflective, with all let-

ters capitalized and having a minimum height of 9.5 mm

(3⁄8 in.), in white on red background.

Change Description: Added requirements for labeling facilities equipped with a rapid shutdown. Impact(s) : No negative impact.

2

VIII. Storage Batteries

690.71 Installation.

(H) Disconnects and Overcurrent Protection. Where en-

ergy storage device input and output terminals are more

than 1.5 m (5 ft) from connected equipment, or where the

circuits from these terminals pass through a wall or parti-

tion, the installation shall comply with the following:

(1) A disconnecting means and overcurrent protection shall

be provided at the energy storage device end of the

circuit. Fused disconnecting means or circuit breakers

shall be permitted to be used.

(2) Where fused disconnecting means are used, the line

terminals of the disconnecting means shall be con-

nected toward the energy storage device terminals.

(3) Overcurrent devices or disconnecting means shall not

be installed in energy storage device enclosures where

explosive atmospheres can exist.

(4) A second disconnecting means located at the connected

equipment shall be installed where the disconnecting

means required by 690.71(H)(1) is not within sight of

the connected equipment.

(5) Where the energy storage device disconnecting means

is not within sight of the PV system ac and dc discon-

necting means, placards or directories shall be installed

at the locations of all disconnecting means indicating

the location of all disconnecting means.

Change Description: Added a new subsection addressing installation of disconnects and overcurrent protection for storage batteries. Impact(s) : Improves safety – no negative impact.

2



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IX. Systems over 6001000 Volts 690.81 Listing. Products listed for PV systems shall be

permitted to be used and installed in accordance with their

listing. PV wire that is listed for direct burial at voltages

above 600 volts, but not exceeding 2000 volts, shall be

installed in accordance with Table 300.50, column 1.

Change Description: This change addresses listing requirements for PV systems over 1000 V. Impact(s) : No negative impact.

2

X. Electric Vehicle Charging

690.90 General. Photovoltaic systems used directly to

charge electric vehicles shall comply with Article 625 in

addition to the requirements of this article.

690.91 Charging Equipment. Electric vehicle couplers

shall comply with 625.10. Personnel protection systems in

accordance with 625.22 and automatic de-energization of

cables in accordance with 625.19 are not required for PV

systems with maximum system voltages of less than

Change Description: Added references to Article 625, Electric Vehicle Charging Systems, for PV systems used directly to charge electric vehicles. Impact(s) : No negative impact.

2

ARTICLE 694 Wind Electric Systems


ARTICLE 695 Fire Pumps

695.3 Power Source(s) for Electric Motor-Driven Fire

Pumps. Electric motor-driven fire pumps shall have a reli-

able source of power.

(F) Transfer of Power. Transfer of power to the fire pump

controller between the individual source and one alternate

source shall take place within the pump room. [20:9.6.4]

(1) Power Source Selection. Selection of power source

shall be performed by a transfer switch listed for fire pump

service. [20:10.8.1.3.1]

(2) Overcurrent Device Selection. An instantaneous trip

circuit breaker shall be permitted in lieu of the overcurrent

Change Description: This change correlates Section 695.3 with NFPA 20. Also, it adds text allowing overcurrent protection device for the fire pump to be provided as a part of transfer switch assembly. Impact(s) : No negative impact.

2



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devices specified in 695.4(B)(2)(a)(1), provided that it is

part of a transfer switch assembly listed for fire pump ser-

vice that complies with 695.4(B)(2)(a)(2).

695.4 Continuity of Power. Circuits that supply electric

motor-–driven fire pumps shall be supervised from inad-

vertent disconnection as covered in 695.4(A) or (B).

(A) Direct Connection. The supply conductors shall di-

rectly connect the power source to either a listed fire pump

controller orcontroller, a listed combination fire pump con-

troller and power transfer switch, or a listed fire pump

power transfer switch.

(B) Connection Through Disconnecting Means and

Overcurrent Device.

(a) Individual Sources. Overcurrent protection for in-

dividual sources shall comply with 695.4(B)(2)(a)(1) or

(2).

(1) The oOvercurrent protective device(s) shall be rated to

carry indefinitely the sum of the locked-rotor current of

largest fire pump motor(s)motor and the pressure

maintenance pump motor(s) and the full-load current of

all of the other pump motors and the associated fire

pump accessory equipment when connected to this

power supply. (…)

(2) Overcurrent protection shall be provided by an assem-

bly listed for fire pump service and complying with the

following:

a. The overcurrent protective device shall not open

within 2 minutes at 600 percent of the full-load

current of the fire pump motor(s).

b. The overcurrent protective device shall not open

with a re-start transient of 24 times the full-load


c. The overcurrent protective device shall not open

within 10 minutes at 300 percent of the full-load


d. The trip point for circuit breakers shall not be

field adjustable. [20:9.2.3.4.1]

Change Description: This change correlates Section 695.4 with NFPA 20. Also, clarifies requirements regarding locking provisions for disconnecting means, consistent with the rest of the code. Impact(s) : No negative impact.

2



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(3) Disconnecting Means. All disconnecting

devices that are unique to the fire pump loads

shall comply with items (a) through (e).

(a) Features and Location — Normal Power Source. The

disconnecting means for the normal power source shall

comply with all of the following: [20:9.2.3.1]

(2) Be lockable in the closed position. The provision for

locking or adding a lock to the disconnecting means

shall be installed on or at the switch or circuit breaker

used as the disconnecting means and shall remain in

place w i t h or without the lock installed.

(3) Not be located within equipment the same enclosure,

panelboard, switchboard, switchgear, or motor control

center, with or without common bus, that feedssupplies

loads other than the fire pump.

(b) Features and Location — On-Site Standby Generator.

The disconnecting means for an on-site standby genera-

tor(s) used as the alternate power source shall be

installed in accordance with 700.10(B)(5) for emergency

circuits and shall be lockable in the closed position. The

provision for locking or adding a lock to the

disconnecting means shall be installed on or at the

switch or circuit breaker used as the disconnecting

means and shall remain in place with or without the

lock installed.

695.6 Power Wiring. Power circuits and wiring methods

shall comply with the requirements in 695.6(A) through (J),

and as permitted in 230.90(A), Exception No. 4; 230.94,

Exception No. 4; 240.13; 230.208; 240.4(A); and 430.31.

(D) Pump Wiring. All wiring from the controllers to the

pump motors shall be in rigid metal conduit, intermediate

metal conduit, electrical metallic tubing, liquidtight flexible

metal conduit, or liquidtight flexible nonmetallic conduit

Type LFNC-B, listed Type MC cable with an impervious

covering, or Type MI cable. Electrical connections at motor

Change Description: Connections in motor terminal boxes made with twist-on, insulation-piercing and soldered connectors have been shown to compromise from motor vibration and thus become a source of failures such as disconnection, overheating, ground fault, and short circuit. Para. 13.5.9.2 of NFPA 79 (Industrial Machinery) already prohibits their use.

Impact(s) :

2



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terminal boxes shall be made with a listed means of con-

nection. Twist-on, insulation-piercing–type, and soldered

wire connectors shall not be permitted to be used for this

purpose.

Improves safety - no negative impact.

ARTICLE 700 Emergency Systems

Relay, Automatic Load Control. A device used to ener-

gize switched set normally dimmed or normally-off switched emergency lighting equipment from an emer-

gency supply to full power illumination levels in the event

of a loss of the normal supply, and to de-energize or supply

by bypassing the dimming/switching controls, and to return

the emergency lighting equipment to normal status when

the device senses the normal supply ishas been restored.

Change Description: Added dimming devices to be overridden by an automatic load control relay. Impact(s) : No negative impact.

2

700.8 Surge Protection. A listed SPD shall be installed in

or on all emergency systems switchboards and panelboards.

Change Description: Added a requirement for a listed surge protection devices to be added in or on all emergency system switchboards and panelboards. Impact(s) : Improves safety - no negative impact.

2

700.10 Wiring, Emergency System.

(D) Fire Protection. Emergency systems shall meet the

additional requirements in (D)(1) through (D)(3) in assem-

bly occupancies for not less than 1000 persons or in build-

ings above 23 m (75 ft) in height with any of the following

occupancy classes: assembly, educational, residential, de-

tention and correctional, business, and mercantile.

Change Description: The need for fire protection of emergency systems is the same regardless of the occupancy classification. This change eliminates potential exclusion of some of the assembly occupancies from the requirements of this section. Impact(s) : No negative impact.

2

700.12 General Requirements.

(B) Generator Set.

(6) Outdoor Generator Sets. Where an outdoor housed

generator set is equipped with a readily accessible discon-

necting means in accordance with 445.18, and the discon-

Change Description: This change clarifies the expectations regarding disconnecting means for outdoor generator sets and provides reference to Section 445.18.

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necting means is located within sight of the building or

structure supplied, an additional disconnecting means shall

not be required where ungrounded conductors serve or pass

through the building or structure. Where the generator sup-

ply conductors terminate at a disconnecting means in or on

a building or structure, Tthe disconnecting means shall

meet the requirements of 225.36.


700.16 Emergency Illumination. Emergency illumination

shall include all required means of egress lighting, illumi-

nated exit signs, and all other lights specified as necessary

to provide required illumination.

Emergency lighting systems shall be designed and in-

stalled so that the failure of any individual lighting element,

such as the burning out of a lamp, cannot leave in total

darkness any space that requires emergency illumination.

Where high-intensity discharge lighting such as high-

and low-pressure sodium, mercury vapor, and metal halide

is used as the sole source of normal illumination, the emer-

gency lighting system shall be required to operate until

normal illumination has been restored.

Where an emergency system is installed, emergency

illumination shall be provided in the area of the disconnect-

ing means required by 225.31 and 230.70, as applicable,

where the disconnecting means are installed indoors.

Change Description: Added a requirement for emergency illumination in the indoor areas of the disconnecting means installed per 225.31 and 230.70. Impact(s) : No negative impact.

2

700.19 Multiwire Branch Circuits. The branch circuit

serving emergency lighting and power circuits shall not be

part of a multiwire branch circuit.

Change Description: This requirement was added to prevent unnecessary opening of one or two poles of a multi-wire branch circuit because of an overload or short circuit on one pole of a multi-wire circuit overcurrent protection. This change is consistent with similar requirement covered in Article 517. Impact(s) : Improves safety - no negative impact.

2

700.24 Directly Controlled Luminaires. Where emer- Change Description: 2



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gency illumination is provided by one or more directly

controlled luminaires that respond to an external control

input to bypass normal control upon loss of normal power,

such luminaires and external bypass controls shall be indi-

vidually listed for use in emergency systems.

This change expands bypass requirements for dimmed luminaires to luminaires with internal onboard dimming capability. Impact(s) : Improves safety - no negative impact.

700.26700.27 Ground-Fault Protection of Equipment.

The alternate source for emergency systems shall not be

required to have ground-fault protection of equipment with

automatic disconnecting means. Ground-fault indication of

the emergency source shall be provided in accordance with

700.6(D).700.6(D) if ground-fault protection of equipment

with automatic disconnecting means is not provided.

Change Description: Reworded section for clarity of intent. Impact(s) : No negative impact.

1

700.27700.28 Selective Coordination.

Emergency system(s) overcurrent devices shall be se-

lectively coordinated with all supply-side overcurrent pro-

tective devices.


professional engineer or other qualified persons engaged

primarily in the design, installation, or maintenance of elec-

trical systems. The selection shall be documented and made



Change Description: The additional language adds a requirement and identifies who is responsible for ensuring selective coordination of an emergency system’s overcurrent devices. Impact(s) : May have an impact on design agencies to have documentation from licensed professional engineer or other qualified person to meet the requirement. No negative impact.

2

ARTICLE 701 Legally Required Standby Systems

701.12 General Requirements.

(B) Generator Set.

(5) Outdoor Generator Sets. Where an outdoor housed








Change Description: This change clarifies the expectations regarding disconnecting means for outdoor generator sets and provides reference to Section 445.18. Impact(s) : No negative impact.

2



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a building or structure, Tthe disconnecting means shall

meet the requirements of 225.36.

701.26 Ground-Fault Protection of Equipment. The al-

ternate source for legally required standby systems shall not be

required to have ground-fault protection of equipment with

automatic disconnecting means. Ground-fault indication of

the legally required standby source shall be provided in

accordance with 701.6(D).701.6(D) if ground-fault protection

of equipment with automatic disconnecting means is not

provided.

Change Description: Reworded section for clarity of intent. Impact(s) : No negative impact.

1

701.27 Selective Coordination. Legally required standby

system(s) overcurrent devices shall be selectively coordi-

nated with all supply-side overcurrent protective devices.







Change Description: The additional language adds a requirement and identifies who is responsible for ensuring selective coordination of an emergency system’s overcurrent devices. Impact(s) : May have an impact on design agencies to have documentation from licensed professional engineer or other qualified person to meet the requirement. No negative impact.

2

ARTICLE 702 Optional Standby Systems

702.7 Signs.

(C) Power Inlet. Where a power inlet is used for a tem-

porary connection to a portable generator, a warning sign

shall be placed near the inlet to indicate the type of derived

system that the system is capable of based on the wiring of

the transfer equipment. The sign shall display one of the

following warnings:

WARNING:

FOR CONNECTION OF A SEPARATELY DERIVED

(BONDED NEUTRAL) SYSTEM ONLY

or

Change Description: A new provision was added requiring a warning sign at the power inlet for temporary connection to a portable generator, indicating type of derived system. Impact(s) : Improves safety - no negative impact.

2



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WARNING:

FOR CONNECTION OF A NONSEPARATELY

DERIVED (FLOATING NEUTRAL) SYSTEM ONLY

702.12 Outdoor Generator Sets.

(A) Permanently Installed Generators and Portable

Generators Greater Than 15 kW. Where an outdoor

housed generator set is equipped with a readily accessible

disconnecting means in accordance with 445.18, and the

disconnecting means is located within sight of the building or



through the building or structure. Where the generator supply

conductors terminate at a disconnecting means in or on a

building or structure, Tthe disconnecting means shall meet

the requirements of 225.36.

B) Portable Generators 15 kW or Less. Where a por-

table generator, rated 15 kW or less, is installed using a

flanged inlet or other cord- and plug-type connection, a

disconnecting means shall not be required where un-

grounded conductors serve or pass through a building or

structure.

Change Description: This change clarifies the expectations regarding disconnecting means for outdoor generator sets and provides reference to Section 445.18. Also, the section is now divided into two subsections, for generators greater than 15 kW and generators 15 kW or less. For generators 15 kW or less this new subsection allows omitting disconnecting means for flanged inlet and cord- and plug-type connection where ungrounded conductors serve or pass through a building or structure. This provision correlates the requirements with revised section 445.18. Impact(s) : No negative impact.

2

ARTICLE 705 Interconnected Electric Power Production Sources

705.12 Point of Connection. The output of an intercon-

nected electric power source shall be connected as specified in

705.12(A), (B), (C), or (D).

(D) Utility-Interactive Inverters.

(2) Bus or Conductor Ampere Rating. The sum of the

ampere ratings of overcurrent devices in circuits supplying

power to a busbar or conductor shall not exceed 120 percent

of the rating of the busbar or conductor.

Exception: Where the photovoltaic system has an energy

storage device to allow stand-alone operation of loads, the

value used in the calculation of bus or conductor loading shall

be 125 percent of the rated utility-interactive current from the

inverter instead of the rating of the overcurrent device

Change Description: Section 705.12(D) was rearranged and reorganized for better clarity. Also, deleted redundant ground-fault protection requirements which are already covered in Section 705.32. Impact(s) : No negative impact.

1



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between the inverter and the bus or conductor.

One hundred twenty-five percent of the inverter output cir-

cuit current shall be used in ampacity calculations for the

following:

(1) Feeders. Where the inverter output connection is made to

a feeder at a location other than the opposite end of the

feeder from the primary source overcurrent device, that

portion of the feeder on the load side of the inverter

output connection shall be protected by one of the

following:

(a) The feeder ampacity shall be not less than the sum

of the primary source overcurrent device and

125 percent of the inverter output circuit current.

(b) An overcurrent device on the load side of the in-

verter connection shall be rated not greater than the

ampacity of the feeder.

(2) Taps.In systems where inverter output connections are

made at feeders, any taps shall be sized based on the

sum of 125 percent of the inverter(s) output circuit current

and the rating of the overcurrent device protecting the

feeder conductors as calculated in 240.21(B).

3) Busbars. One of the methods that follows shall be used to

determine the ratings of busbars in panelboards.

(a) The sum of 125 percent of the inverter(s) output

circuit current and the rating of the overcurrent

device protecting the busbar shall not exceed the

ampacity of the busbar.

(b) Where two sources, one a utility and the other an

inverter, are located at opposite ends of a busbar

that contains loads, the sum of 125 percent of the

inverter(s) output circuit current and the rating of

the overcurrent device protecting the busbar shall

not exceed 120 percent of the ampacity of the

busbar. The busbar shall be sized for the loads

connected in accordance with Article 220. A

permanent warning label shall be applied to the

distribution equipment adjacent to the back-fed



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breaker from the inverter that displays the

following or equivalent wording:

WARNING:

INVERTER OUTPUT CONNECTION;

DO NOT RELOCATE THIS OVERCURRENT

DEVICE.

The warning sign(s) or label (s) shall comply

with 110.21(B).

(c) The sum of the ampere ratings of all

overcurrent devices on panelboards, both load and

supply devices, excluding the rating of the

overcurrent device protecting the busbar, shall not

exceed the ampacity of the busbar. The rating of

the overcurrent device protecting the busbar shall

not exceed the rating of the busbar. Permanent

warning labels shall be applied to distribution

equipment that displays the following or

equivalent wording:

WARNING:

THIS EQUIPMENT FED BY MULTIPLE SOURCES.

TOTAL RATING OF ALL OVERCURRENT

DEVICES, EXCLUDING MAIN SUPPLY

OVERCURRENT DEVICE,

SHALL NOT EXCEED AMPACITY OF

BUSBAR.

The warning sign(s) or label (s) shall comply

with

110.21(B).

(d) Connections shall be permitted on multiple-

ampacity busbars or center-fed panelboards where

designed under engineering supervision that

includes fault studies and busbar load

calculations.

(3) Ground-Fault Protection. The interconnection point

shall be on the line side of all ground-fault protection

equipment.



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Exception: Connection shall be permitted to be made to the

load side of ground-fault protection, provided that there is

ground-fault protection for equipment from all ground- fault

current sources. Ground-fault protection devices used with

supplies connected to the load-side terminals shall be

identified and listed as suitable for backfeeding.

(7) Inverter Output Connection. Unless the panelboard is

rated not less than the sum of the ampere ratings of all

overcurrent devices supplying it, a connection in a panel-

board shall be positioned at the opposite (load) end from

the input feeder location or main circuit location. The bus or

conductor rating shall be sized for the loads connected in

accordance with Article 220. In systems with panelboards

connected in series, the rating of the first overcurrent device

directly connected to the output of a utility-interactive in-

verter(s) shall be used in the calculations for all busbars and

conductors. A permanent warning label shall be applied to

the distribution equipment with the following or equivalent

wording:

WARNING

INVERTER OUTPUT

CONNECTION DO NOT

RELOCATE THIS

OVERCURRENT DEVICE

(6) Wire Harness and Exposed Cable Arc-Fault

Protection. A utility-interactive inverter(s) that has a wire

harness or cable output circuit rated 240 V, 30 amperes, or

less, that is not installed within an enclosed raceway, shall

be provided with listed ac AFCI protection.

705.31 Location of Overcurrent Protection. Overcurrent

protection for electric power production source conductors,

connected to the supply side of the service disconnecting

means in accordance with 705.12(A), shall be located

within 3 m (10 ft) of the point where the electric power

production source conductors are connected to the service.

Exception: Where the overcurrent protection for the power

Change Description: This new section provides requirements for placing overcurrent protection within three meters from the point where the electric power production source conductors are connected to the service. If the distance from the connection point to the overcurrent protection device exceeds 3 meters, the new exception allows using cable limiters or current-limited circuit

2



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production source is located more than 3 m (10 ft) from the

point of connection for the electric power production

source to the service, cable limiters or current-limited cir-

cuit breakers for each ungrounded conductor shall be in-

stalled at the point where the electric power production

conductors are connected to the service.

breakers at the connection point as a protection for the otherwise unprotected conductors. Impact(s) : Improves safety - no negative impact.

705.100 Unbalanced Interconnections.

(A) Single Phase. Single-phase inverters for hybrid sys-

tems and ac modules in interactive hybrid systems shall not

be connected to 3three-phase power systems unless the in-

terconnected system is designed so that significant unbal-

anced voltages cannot result.in order to limit unbalanced

voltages to not more than 3 percent.

Change Description: Removed unenforceable language (i.e., “significant”) and replaced it with a specific value of an acceptable voltage unbalance. Impact(s) : No negative impact.

2

ARTICLE 708 Critical Operations Power Systems (COPS)

708.14 Wiring of HVAC, Fire Alarm, Security, Emer-

gency Communications, and Signaling Systems. All con-

ductors or cables shall be installed using any of the metal

wiring methods permitted by 708.10(C)(1) and, in addition,

shall comply with 708.14(1) through (8), as applicable.

(1) All cables for fire alarm, security, signaling systems,

and emergency communications shall be shielded

twisted pair cables or installed to comply with the per-

formance requirements of the system.

(2) Shields of cables for fire alarm, s e c u r i t y , signaling

systems, and emergency communications shall be

continuous. arranged in accordance with the

manufacturer’s published installation instructions.

(7) All cables for fire a l a r m , security, and signaling

systems shall be riser-rated and shall be a listed 2-

hour electrical circuit protective system. Riser

emergency Emergency communication cables shall

be Type CMR-CI or shall be riser-rated and shall

Change Description: Reworded section for clarity of intent and added a riser-rated cable as an acceptable emergency communication cable. Impact(s) : No negative impact.

2



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be a listed 2-hour electrical circuit protective system.

708.20 Sources of Power.

(F) Generator Set.

(5) Outdoor Generator Sets.

(a) Permanently Installed Generators and Portable

Generators Greater Than 15 kW. Where an outdoor housed








a building or structure, the disconnecting means shall meet

the requirements of 225.36.

(b) Portable Generators 15 kW or Less. Where a por-

table generator, rated 15 kW or less, is installed using a

flanged inlet or other cord-and plug-type connection, a dis-

connecting means shall not be required where ungrounded

conductors serve or pass through a building or structure.

Change Description: Revised to correlate with changes in Articles 700, 701, and 702. This change clarifies the expectations regarding disconnecting means for outdoor generator sets and provides reference to Section 445.18. Also, the section is now divided into two subsections, for generators greater than 15 kW and generators 15 kW or less. For generators 15 kW or less this new subsection allows omitting disconnecting means for flanged inlet and cord- and plug-type connection where ungrounded conductors serve or pass through a building or structure. This provision correlates the requirements with revised Section 445.18. Impact(s) : No negative impact.

2

708.52 Ground-Fault Protection of Equipment.

(D) Selectivity. Ground-fault protection for operation of

the service and feeder disconnecting means shall be fully

selective such that the feeder device, but not the service

device, shall open on ground faults on the load side of the

feeder device. A six-cycle minimum separation between the

service and feeder Separation of ground-fault tripping

bands protection time-current characteristics shall be pro-

vided. conform to the manufacturer’s recommendations

Operating time of the disconnecting devices shall be con-

sidered in selecting the time spread between these two

bands and shall consider all required tolerances and discon-

nect operating time to achieve 100 percent selectivity.

Change Description: Revised to reflect changes to Section 517.17(C), introduced in 2008 edition of the Code. This change improves selective coordination for COPS. Impact(s) : No negative impact.

2

708.54 Selective Coordination. Critical operations power

system(s) overcurrent devices shall be selectively coordi-

nated with all supply-side overcurrent protective devices.


Change Description: The additional language adds a requirement and identifies who is responsible for ensuring selective coordination of a COPS’

2



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Exception: Selective coordination shall not be required

between two overcurrent devices located in series if no

loads are connected in parallel with the downstream

device.

overcurrent devices. Impact(s) : May have an impact on design agencies to have documentation from licensed professional engineer or other qualified person to meet the requirement. No negative impact.

ARTICLE 725 Class 1, Class 2, and Class 3

Remote-Control, Signaling, and Power-Limited Circuits

Power-Limited Tray Cable (PLTC). A factory assembly of

two or more insulated conductors rated at 300 V, with or

without associated bare or insulated equipment grounding

conductors, under a nonmetallic jacket.

Change Description: Added definition for Power-Limited Tray Cable. Impact(s) : No negative impact.

1

725.49 Class 1 Circuit Conductors.

(B) Insulation. Insulation on conductors shall be rated for

the system voltage and not less than 600 volts.

Change Description: Clarified the language regarding applicability of this Article regarding Class 1 circuit conductor insulation. Impact(s) : No negative impact.

1

725.135 Installation of Class 2, Class 3, and PLTC

Cables. Installation of Class 2, Class 3, and PLTC cables

shall comply with 725.135(A) through (M).

(A) Listing. Class 2, Class 3, and PLTC cables installed in

buildings shall be listed.

(B) Fabricated Ducts Used for Environmental Air. The

Change Description: Added new section addressing installation of Class 2, Class 3, and PLTC cables, similar to Section 800.13, covering communication circuits, including plenum grade cable routing assemblies. This is a companion change to the revision of Section 725.154, separating application and installation rules in to two sections.

2



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following wires and cables shall be permitted in ducts used

for environmental air as described in 300.22(B) if they are

directly associated with the air distribution system:

(1) Types CL2P and CL3P cables in lengths as short as

practicable to perform the required function

(2) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, CL2X,

CL3X, and PLTC cables installed in raceways that are

installed in compliance with 300.22(B)


nums). The following cables shall be permitted in other

spaces used for environmental air as described in

300.22(C):

(1) Types CL2P and CL3 cables

(2) Types CL2P and CL3P cables installed in plenum com-

munications raceways

(3) Types CL2P and CL3P cables and plenum communica-

tions raceways supported by open metallic cable trays

or cable tray systems


CL3X, and PLTC cables installed in raceways that are

installed in compliance with 300.22(C)


CL3X, and PLTC cables supported by solid bottom

metal cable trays with solid metal covers in other

spaces used for environmental air (plenums) as de-

scribed in 300.22(C)


CL3X, and PLTC cables installed in plenum communi-

cations raceways, riser communications raceways, and

general-purpose communications raceways supported

by solid bottom metal cable trays with solid metal cov-

ers in other spaces used for environmental air (ple-

nums) as described in 300.22(C)

(D) Risers — Cables in Vertical Runs. The following

cables shall be permitted in vertical runs penetrating one or

more floors and in vertical runs in a shaft:




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(1) Types CL2P, CL3P, CL2R, and CL3R cables

(2) Types CL2P, CL3P, CL2R, and CL3R cables installed

in the following:

a. Plenum communications raceways

b. Plenum cable routing assemblies

c. Riser communications raceways

d. Riser cable routing assemblies

(E) Risers — Cables in Metal Raceways. The following

cables shall be permitted in metal raceways in a riser hav-

ing firestops at each floor:


CL3X, and PLTC cables


CL3X, and PLTC cables installed in the following:


b. Riser communications raceways

c. General-purpose communications raceways

(F) Risers — Cables in Fireproof Shafts. The following

shall be permitted to be installed in fireproof riser shafts

having firestops at each floor:


CL3X, and PLTC cables

(2) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3, and

PLTC cables installed in the following:





e. General-purpose communications raceways

f. General-purpose cable routing assemblies

(G) Risers — One- and Two-Family Dwellings. The

following cables shall be permitted in one- and two-family

dwellings:



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PLTC cables

(2) Types CL2X and CL3X cables less than 6 mm

(0.25 in.) in diameter









(H) Cable Trays. Cables installed in cable trays outdoors

shall be Type PLTC. The following cables shall be permit-

ted to be supported by cable trays in buildings:

(1) Types CM CL2P, CL3P, CL2R, CL3R, CL2, CL3, and

PLTC cables




b. Riser communications raceways

c. General-purpose communications raceways

(I) Cross-Connect Arrays. The following cables shall be

permitted to be installed in cross-connect arrays:


PLTC cables









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(J) Industrial Establishments. In industrial establish-

ments where the conditions of maintenance and supervision

ensure that only qualified persons service the installation,

Type PLTC cable shall be permitted in accordance with

either (1) or (2) as follows:

(1) Where the cable is not subject to physical damage,

Type PLTC cable that complies with the crush and im-

pact requirements of Type MC cable and is identified as

LTC-ER for such use shall be permitted to be exposed

between the cable tray and the utilization equipment or

device. The cable shall be continuously supported and

protected against physical damage using mechanical

protection such as dedicated struts, angles, or channels.

The cable shall be supported and secured at intervals

not exceeding 1.8 m (6 ft).

(2) Type PLTC cable, with a metallic sheath or armor in

accordance with 725.179(E), shall be permitted to be

installed exposed. The cable shall be continuously

supported and protected against physical damage

using mechanical protection such as dedicated struts,

angles, or channels. The cable shall be secured at

intervals not exceeding 1.8 m (6 ft).

(K) Other Building Locations. The following wires and

cables shall be permitted to be installed in building loca-

tions other than the locations covered in 725.135(B)

through (I):


PLTC cables

(2) A maximum of 3 m (10 ft) of exposed Type CL2X wires

and cables in nonconcealed spaces

(3) A maximum of 3 m (10 ft) of exposed Type CL3X wires

and cables in nonconcealed spaces





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CL3X, and PLTC cables installed in raceways recog-

nized in Chapter 3

(6) Type CMUC undercarpet communications wires and

cables installed under carpet

(L) Multifamily Dwellings. The following wires and

cables shall be permitted to be installed in multifamily

dwellings in locations other than the locations covered in

725.135(B) through (I):


PLTC wires and cables

(2) Type CL2X wires and cables less than 6 mm (0.25 in.)

in diameter in nonconcealed spaces


in diameter in nonconcealed spaces


PLTC wires and cables installed in the following:







(5) Types CL2P, CL3P, CL2R, CL3R, CL2, CL3,

CL2X, CL3X, and PLTC wires and cables installed

in raceways recognized in Chapter 3

(6) Type CMUC undercarpet communications wires

and cables installed under carpet



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(M) One- and Two-Family Dwellings. The following

wires and cables shall be permitted to be installed in one-

and two-family dwellings in locations other than the loca-

tions covered in 725.135(B) through (I):


PLTC wires and cables


in diameter


in diameter

(4) Communications wires and Types CL2P, CL3P, CL2R,

CL3R, CL2, CL3, and PLTC cables installed in the

following:








CL3X, and PLTC wires and cables installed in race-

ways recognized in Chapter 3

(6) Type CMUC undercarpet communications wires and

cables installed under carpet

725.154 Applications of Listed Class 2, Class 3, and

PLTC Cables. Class 2, Class 3, and PLTC cables shall

comply with any of the requirements described in

25.154(A) through (I). (C) and as indicated in Table

725.154.

(GA) Class 2 and Class 3 Cable Substitutions. The sub-

stitutions for Class 2 and Class 3 cables listed in

Table 725.154(GA) and illustrated in Figure 725.154(GA)

shall be permitted. Where substitute cables are installed, the

wiring requirements of Article 725, Parts I and III, shall

Change Description: Converted descriptive portion of this section to a table format (Table 725.154). This is a companion change to the added Section 725.135, separating application and installation rules in to two sections.


1



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apply.

725.179 Listing and Marking of Class 2, Class 3, and

Type PLTC Cables; Communications Raceways; and

Cable Routing Assemblies. Class 2, Class 3, and Type

PLTC cables and cables, nonmetallic signaling raceways

and cable routing assemblies installed as wiring methods

within buildings shall be listed as being resistant to the

spread of fire and other criteria in accordance with

725.179(A) through (K)(J) and shall be marked in accor-

dance with 725.179(L).725.179 (K).

(F) Circuit Integrity (CI) Cable or Electrical Circuit

Protective System. Cables that are used for survivability of

critical circuits under fire conditions shall be listed as cir-

cuit integrity (CI) cable.meet either 725.179(F)(1) or (F)(2)

as follows:

(1) Circuit Integrity (CI) Cables. Circuit Integrity (CI)

cables, specified in 725.154(A), and (B), used for surviv-

ability of critical circuits, shall have the additional classifi-

cation using the suffix “CI.” Circuit integrity (CI) cables

shall only be permitted to be installed in a raceway where

specifically listed and marked as part of an electrical circuit

protective system as covered in 725.179(F)(2).

(2) Electrical Circuit Protective System. Cables specified

in 725.154(A), and (B), (D)(1), and (E), and used for circuit

integrity that are part of an electrical circuit protective sys-

tem shall have the additional classification using the suffix

“-CI”. Cables that are part of a listed electrical circuit protec-

tive system shall be considered to meet the requirements of

survivability. be identified with the protective system number

and hourly rating printed on the outer jacket of the cable and

installed in accordance with the listing of the protective sys-

tem.

Change Description: This change separates the two methods of establishing cable survivability. Cable are either tested as a CI cable or tested as part of an electrical circuit protective system. The new text clarifies the two cable options and marking requirements. Impact(s) : No negative impact.

2





Change Description: Revised to reflect nomenclature change from “signaling raceway” to “communication raceway”.

1



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dance with 725.179(L).725.179 (K).

(I) Plenum Signaling Raceways. Plenum signaling race-

ways shall be listed as having adequate fire-resistant and

low smoke-producing characteristics.










dance with 725.179(L).725.179 (K).

(JI) Riser Signaling Raceways.Cable Routing Assem-

blies. Riser signaling raceways cable routing assemblies

shall be listed as having adequate fire-resistant characteris-

tics capable of preventing the carrying of fire from floor to

floor.

Change Description: Revised to reflect nomenclature change from “signaling raceway” to “communication raceway” and addition of cable routing assemblies. Impact(s) : No negative impact.

2









dance with 725.179(L).725.179 (K).

(KJ) General-Purpose Signaling Raceways.General-

Use Cable Routing Assemblies. General-purpose signaling

racewaysGeneral-use cable routing assemblies shall be

listed as being resistant to the spread of fire.

Change Description: Revised to reflect nomenclature change from “signaling raceway” to “communication raceway” and addition of cable routing assemblies. Impact(s) : No negative impact.

2



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ARTICLE 728 Fire-Resistive Cable Systems

Added a new Article. The text of this new article not

included for brevity. Change Description: This new articles provides installation requirements for fire-resistive cable systems. Impact(s) : No negative impact.

2

ARTICLE 750 Energy Management System

Added a new Article. The text of this new article not included

for brevity. Change Description: This new article provides requirements for installation and operation of energy management systems. Impact(s) : No negative impact.

2

ARTICLE 760 Fire Alarm Systems

760.24 Mechanical Execution of Work.

(B) Circuit Integrity (CI) Cable. Circuit in tegr i ty

(CI) cables shall be supported at a distance not

exceeding 610 mm (24 in.). Where located within 2.1 m (7

ft) of the floor, as covered in 760.53(A)(1) and 760.130(1),

as applicable, the cable shall be fastened in an approved

manner at intervals of not more than 450 mm (18 in.). Cable

supports and fasteners shall be steel.

Change Description: This change correlates the installation requirements for CI cables with UL 2196 testing for the cable. Impact(s) : No negative impact.

2

760.32 Fire Alarm Circuits Extending Beyond One

Building. PowerNon–power-limited fire alarm circuits and

power-limited fire alarm circuits that extend beyond one

building and run outdoors either shall meet the installation

Change Description: As a result of this change all non-power-limited and power-limited signaling system circuits entering a building must be now

2



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requirements of Parts II, III, and IV of Article 800 or shall

meet the installation requirements of Part I of Article 300.

Non–power-limited fire alarm circuits that extend beyond

one building and run outdoors and shall meet the installa-

tion requirements of Part I of Article 300 and the applicable

sections of Part I of Article 225.

provided with transient protection. This change is consistent with the changes to NFPA 72. Impact(s) : Improves safety of fire alarm circuits – no negative impact.

760.51 Number of Conductors in Cable Trays and

Raceways, and Ampacity Adjustment Factors.

(B) Power-Supply Conductors and Fire AlarmNPLFA

Circuit Conductors. Where power-supply conductors and

non–power-limited fire alarm circuit conductors are permit-

ted in a raceway in accordance with 760.48, the number of

conductors shall be determined in accordance with 300.17.

The ampacity adjustment factors given in 310.15(B)(3)(a)

shall apply as follows:

Change Description: Revised to clarify that this section applies only to non-power limited circuits. Impact(s) : No negative impact.

1

760.135 Installation of PLFA Cables in Buildings. In-

stallation of power-limited fire alarm cables in buildings

shall comply with 760.135(A) through (J).

(The full text of the article is not included)

Change Description: Added new section addressing installation of PLFA cables. This is a companion change to the revision of Section 760.154, separating application and installation rules in to two sections. Impact(s) : No negative impact.

1

760.154 Applications of Listed PLFA Cables. PLFA

cables shall comply with the requirements described in ei-

ther 760.154(A), (B), or (C) Table 760.154 or where cable

substitutions are made as shown in 760.154(D)760.154(A).

Where substitute cables are installed, the wiring require-

ments of Article 760, Parts I and III, shall apply. Types

FPLP-CI, FPLR-CI, and FPL-CI cables shall be permitted

to be installed to provide 2-hour circuit integrity rated

cables.

(A) Plenum. Cables installed in ducts, plenums, and other

spaces used for environmental air shall be Type FPLP.

Types FPLP, FPLR, and FPL cables installed in compliance

Change Description: Converted descriptive portion of this section to a table format (Table 760.154). This is a companion change to the added Section 760.135, separating application and installation rules in to two sections. Impact(s) : No negative impact.

1



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with 300.22 shall be permitted. Type FPLP-CI cable shall

be permitted to be installed to provide a 2-hour circuit

integrity rated cable.

(B) Riser. Cables installed in risers shall be as described in

either (1), (2), or (3):

(1) Cables installed in vertical runs and penetrating more

than one floor, or cables installed in vertical runs in a

shaft, shall be Type FPLR. Floor penetrations requiring

Type FPLR shall contain only cables suitable for riser

or plenum use. Type FPLR-CI cable shall be permitted

to be installed to provide a 2-hour circuit integrity rated

cable.

(2) Other cables shall be installed in metal raceways or

located in a fireproof shaft having firestops at each

floor.

(3) Type FPL cable shall be permitted in one- and two-

family dwellings.

Informational Note: See 300.21 for firestop requirements for

floor penetrations.

(C) Other Wiring Within Buildings. Cables installed in

building locations other than those covered in 760.154(A)

or (B) shall be as described in either (C)(1), (C)(2), (C)(3),

or (C)(4). Type FPL-CI cable shall be permitted to be in-

stalled as described in either (C)(1), (C)(2), (C)(3), or

(C)(4) to provide a 2-hour circuit integrity rated cable.

(1) General. Type FPL shall be permitted.

(2) In Raceways. Cables shall be permitted to be installed

in raceways.

(3) Nonconcealed Spaces. Cables specified in Chapter 3

and meeting the requirements of 760.179(A) and (B) shall

be permitted to be installed in nonconcealed spaces where

the exposed length of cable does not exceed 3 m (10 ft).

(4) Portable Fire Alarm System. A portable fire alarm



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system provided to protect a stage or set when not in use

shall be permitted to use wiring methods in accordance

with 530.12.

760.176 Listing and Marking of NPLFA Cables. Non–

power-limited fire alarm cables installed as wiring within

buildings shall be listed in accordance with 760.176(A) and

(B) and as being resistant to the spread of fire in accordance

with 760.176(C) through (F), and shall be marked in accor-

dance with 760.176(G). Cable used in a wet location shall

be listed for use in wet locations or have a moisture-

impervious metal sheath.

(F) Fire Alarm Circuit Integrity (CI) Cable or Electri-

cal Circuit Protective System. Cables that are used for

survivability of critical circuits shall be listed as circuit

integrity (CI) cable. Cables specified in 760.176(C), (D),

and (E), and used for circuit integrity shall have the addi-

tional classification using the suffix “-CI.” Cables that are

part of a listed electrical circuit protective system shall be

considered to meet the requirements of survivability.under

fire conditions shall meet either 760.176(F)(1) or (F)(2) as

follows:

(1) Circuit Integrity (CI) Cables. Circuit integrity (CI)

cables, specified in 760.176(C), (D), and (E), and used for

survivability of critical circuits, shall have an additional

classification using the suffix “CI.” Circuit integrity (CI)

cables shall only be permitted to be installed in a raceway

where specifically listed and marked as part of an electrical

circuit protective system as covered in 760.176(F)(2).

(2) Electrical Circuit Protective System. Cables specified

in 760.176(C), (D), (E), and (F)(1), that are part of an

electrical circuit protective system, shall be identified with

the protective system number and hourly rating printed on

the outer jacket of the cable and installed in accordance

with the listing of the protective system.

Change Description: This change separates the two methods of establishing cable survivability. Cable are either tested as a CI cable or tested as part of an electrical circuit protective system. The new text clarifies the two cable options and marking requirements. Impact(s) : No negative impact.

2

760.179 Listing and Marking of PLFA Cables and In- Change Description: 2



of 203

sulated Continuous Line-Type Fire Detectors. PLFA

cables installed as wiring within buildings shall be listed as

being resistant to the spread of fire and other criteria in

accordance with 760.179(A) through (H) and shall be

marked in accordance with 760.179(I). Insulated continu-

ous line-type fire detectors shall be listed in accordance

with 760.179(J). Cable used in a wet location shall be listed

for use in wet locations or have a moisture-impervious

metal sheath.

(G) Fire Alarm Circuit Integrity (CI) Cable or Electri-

cal Circuit Protective System. Cables that are used for

survivability of critical circuits shall be listed as circuit

integrity (CI) cable. Cables specified in 760.179(D), (E),

(F), and (H) and used for circuit integrity shall have the

additional classification using the suffix “-CI.” Cables that

are part of a listed electrical circuit protective system shall

be considered to meet the requirements of survivabili-

ty.under fire conditions shall meet either 760.179(G)(1) or

(G)(2) as follows:

(1) Circuit Integrity (CI) Cables. Circuit integrity (CI) cables

specified in 760.179(D), (E), (F), and (H), and used for


classification using the suffix “CI.” Circuit integrity (CI)

cables shall only be permitted to be installed in a raceway

where specifically listed and marked as part of an electrical

circuit protective system as covered in 760.179(G)(2).

(2) Electrical Circuit Protective System. Cables specified in

760.179(D), (E), (F), (H), and (G)(1), that are part of an

electrical circuit protective system, shall be identified with the

protective system number and hourly rating printed on the

outer jacket of the cable and installed in accordance with

the listing of the protective system.

This change separates the two methods of establishing cable survivability. Cable are either tested as a CI cable or tested as part of an electrical circuit protective system. The new text clarifies the two cable options and marking requirements. Impact(s) : No negative impact.

ARTICLE 770

Optical Fiber Cables and Raceways

770.3 Other Articles. Installations of optical fiber cables Change Description: 2



of 203

and raceways shall comply with 770.3(A) and (B). Only

those sections of Chapter 2 and Article 300 referenced in

this article shall apply to optical fiber cables and raceways.

(B) Cables in Ducts for Dust, Loose Stock, or Vapor

Removal. The requirements of 300.22(A) for wiring sys-

tems shall apply to conductive optical fiber cables.

Added new subsection to provide requirements for optical fiber cables, similar to Section 800.3. Impact(s) : No negative impact.

770.24 Mechanical Execution of Work. Optical fiber

cables shall be installed in a neat and workmanlike manner.

Cables installed exposed on the surface of ceilings and

sidewalls shall be supported by the building structure in

such a manner that the cable will not be damaged by nor-

mal building use. Such cables shall be secured by hardware

including straps, staples, cable ties, hangers, or similar fit-

tings designed and installed so as not to damage the cable.

The installation shall also conform with 300.4(D) and

300.11.300.4(D) through (G) and 300.11. Nonmetallic

cable ties and other nonmetallic cable accessories used to

secure and support cables in other spaces used for environ-

mental air (plenums) shall be listed as having low smoke

and heat release properties.

Change Description: Revised to correlate with requirements in NFPA 90A, providing criteria for cable ties and accessories installed in plenums. Impact(s) : No negative impact.

2

770.47 Underground Optical Fiber Cables Entering

Buildings. Underground optical fiber cables entering build-

ings shall comply with 770.47(A) and (B).

(A) Underground Systems with Electric Light, Power,

Class 1, or Non–Power-Limited Fire Alarm Circuit

Conductors. Underground conductive optical fiber cables

entering buildings with electric light, power, Class 1, or

non– power-limited fire alarm circuit conductors in a race-

way, handhole enclosure, or manhole shall be located in a

section separated from such conductors by means of brick,

concrete, or tile partitions or by means of a suitable barrier.

(B) Direct-Buried Cables and Raceways. Direct-buried

conductive optical fiber cables shall be separated by at least

300 mm (12 in.) from conductors of any electric light,

power, or non–power-limited fire alarm circuit conductors

Change Description: Added new section addressing underground optical fiber cables entering buildings, similar to the sections in Articles 800, 820, 830, and 840. Impact(s) : No negative impact.

2



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or Class 1 circuit.

Exception No. 1: Direct-buried conductive optical fiber

cables shall not be required to be separated by at least

300 mm (12 in.) from electric service conductors where

electric service conductors are installed in raceways or

have metal cable armor.

Exception No. 2: Direct-buried conductive optical fiber

cables shall not be required to be separated b y at

least 300 mm (12 in.) from electric light or power branch-

circuit or feeder conductors, non–power-limited fire alarm

circuit conductors, or Class 1 circuit conductors where

electric light or power branch-circuit or feeder

conductors, non– power-limited fire alarm circuit

conductors, or Class 1 circuit conductors are installed in

a raceway or in metal- sheathed, metal-clad, or Type UF

or Type USE cables.

770.49 Metallic Entrance Conduit Grounding. Rigid

metal conduit (RMC) or intermediate metal conduit (IMC)

containing optical fiber entrance cable shall be connected

by a bonding conductor or grounding electrode conductor

to a grounding electrode in accordance with 770.100(B).

Change Description: Moved the definition containing a requirement to a new section to comply with NEC Style Manual. Impact(s) : No negative impact.

1

770.100 Entrance Cable Bonding and Grounding.

Where required, the non–current-carrying metallic mem-

bers of optical fiber cables entering buildings shall be

bonded or grounded as specified in 770.100(A) through

(D).

(A) Bonding Conductor or Grounding Electrode Con-

ductor.

(4) Length. The bonding conductor or grounding electrode

conductor shall be as short as practicable. In one- and two-

family dwellings, the bonding conductor or grounding elec-

trode conductor shall be as short as practicable not to ex-

ceed 6.0 m (20 ft) in length.

Change Description: Added new subsection, providing bonding and grounding conductor length and protection requirements, similar to Articles 800, 820, and 830. Impact(s) : No negative impact.

2



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Exception: In one- and two-family dwellings where it is not

practicable to achieve an overall maximum bonding con-

ductor or grounding electrode conductor length of 6.0 m

(20 ft), a separate ground rod meeting the minimum dimen-

sional criteria of 770.100(B)(3)(2) shall be driven, the

grounding electrode conductor shall be connected to the

separate ground rod in accordance with 770.100(C), and

the separate ground rod shall be bonded to the power

grounding electrode system in accordance with 770.100(D).

(56) Physical Damage.Protection. Where necessary, the

bonding conductor Bonding conductors and grounding

electrode conductors shall be guarded from protected where

exposed to physical damage. Where these conductors are

the bonding conductor or grounding electrode conductor is

installed in a metal raceway, both ends of the raceway shall

be bonded to the contained conductors or to the same ter-

minal or electrode to which the conductor(s) is (are)bond-

ing conductor or grounding electrode conductor is con-

nected.

770.110 Raceways and Cable Routing Assemblies for

Optical Fiber Cables.

(A) Types of Raceways. Optical fiber cables shall be per-

mitted to be installed in any raceway that complies with

either 770.110(A)(1) or (A)(2) and in cable routing assem-

blies installed in compliance with 770.110(C).

(2) Other PermittedCommunications Raceways. Optical

fiber cables shall be permitted to be installed in listed ple-

num optical fiber raceway, listed plenum communications

raceways, listed riser optical fiber raceway, listed riser com-

munications raceway, listed general-purpose optical fiber

raceway, or raceways, and listed general-purpose commu-

nications raceways selected in accordance with the provisions

of 770.113, 800.110, and 800.113, and installed in accordance

with 362.24 through 362.56, where the requirements appli-

cable to electrical nonmetallic tubing (ENT) apply.

Change Description: This change is one of a series of changes simplifying types of raceways specified in Articles 770, 800, and 820. Impact(s) : No negative impact.

1


Optical Fiber Cables. Change Description: This added subsection provides installation rules for cable routing

2



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(C) Cable Routing Assemblies. Optical fiber cables shall

be permitted to be installed in plenum cable routing assem-

lies, riser cable routing assemblies, and general-purpose

cable routing assemblies selected in accordance with the

provisions of 800.113 and Table 800.154(c) and installed in

accordance with 770.110(C)(1) and (C)(2).

(1) Horizontal Support. Cable routing assemblies shall be

supported where run horizontally at intervals not to exceed

900 mm (3 ft), and at each end or joint, unless listed for

other support intervals. In no case shall the distance be-

tween supports exceed 3 m (10 ft).

(2) Vertical Support. Vertical runs of cable routing assem-

blies shall be supported at intervals not exceeding 1.2 m

(4 ft), unless listed for other support intervals, and shall not

have more than one joint between supports.

assemblies. Impact(s) : No negative impact.

770.113 Installation of Optical Fiber Cables and Race-

ways, and Cable Routing Assemblies.Cables. Installation of

optical fiber cables and raceways, and cable routing assem-

blies shall comply with 770.113(A) through (J). Installation

of raceways shall also comply with 770.12 and 770.110.

(A) Listing. Optical fiber cables and raceways, and cable

routing assemblies installed in buildings shall be listed.

(C) Other Spaces Used For Environmental Air (Ple-

nums). The following cables and raceways shall be permit-

ted in other spaces used for environmental air as described

in 300.22(C):

(1) Types OFNP and OFCP cables

(2) Plenum optical fiber racewayTypes OFNP and OFCP

cables installed in plenum communications raceways

(3) Types OFNP and OFCP cables installed in plenum optical

fiber racewaysupported by open metallic cable trays or

plenum communications raceway cable tray systems

(4) Types OFNP and OFCP cables and plenum optical fiber

raceways supported by open metallic cable trays or cable

tray systemsOFNP, OFCP, OFNR, OFCR, OFNG,

OFCG, OFN, and OFC cables installed in raceways that are

Change Description: This change is one of a series of changes simplifying types of raceways specified in Articles 770, 800, and 820. This includes deletion of Section 770.182. Impact(s) : No negative impact.

2



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installed in compliance with 300.22(C)

(5) Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG,

OFN, and OFC cables installed in raceways that are

installed supported by solid bottom metal cable trays with

solid metal covers in other spaces used for environmental

air (plenums), in compliance with as described in

300.22(C)

(6) Types OFNP, OFCP, OFNR, OFCR, OFNG, OFCG,

OFN, and OFC cables and installed in plenum optical

fiber communications raceways, riser optical fiber race-

ways and communications raceways, or general-

purpose optical fiber communications raceways sup-

ported by solid bottom metal cable trays with solid metal

covers in other spaces used for environmental air (plenums),

as described in 300.22(C)

770.179 Optical Fiber Cables.

Optical fiber cables shall be listed in accordance with

770.179(A) through (E)(F) and shall be marked in

accordance with Table 770.179. Optical fiber cables shall

have a temperature rating of not less than 60°C (140°F).

(E) Optical Fiber Circuit Integrity (CI) Cables or Elec-

trical Circuit Protective System. Cables suitable for use

in systems to ensure that are used for survivability of criti-

cal circuits and pathways during a specified time under fire

conditions shall be additionally listed as circuit integrity

(CI) cable. Cables identified in 770.179(A) through (D) that

meet the requirements for circuit integrity shall have the

additional classification using the suffix “CI.”and meet ei-

ther 770.179(E)(1) or (E)(2).

770.182 Optical Fiber Raceways and Cable Routing

Assemblies.(1) Circuit Integrity (CI) Cables. Optical

fiber raceways and cable routing assemblies shall be listed

in accordance with 770.182(A) through (C). Circuit

integrity (CI) cables specified in 770.179(A) through (D),

and used for survivability of critical circuits, shall have an

additional classification using the suffix “CI.” In order to

Change Description: This change separates the two methods of establishing cable survivability. Cable are either tested as a CI cable or tested as part of an electrical circuit protective system. The new text clarifies the two cable options and marking requirements. The added subsection (F) covers marking and listing requirements for field-assembled optical fiber cables. Impact(s) : No negative impact.

2



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maintain its listed fire rating, circuit integrity (CI) cable

shall only be installed in free air.

(A) Plenum Optical Fiber Raceway. Plenum optical fiber

raceways shall be listed as having adequate fire-resistant and

low smoke-producing characteristics.

(B2) Riser Optical Fiber Raceways and Cable Routing

Assemblies. Fire-Resistive Cables. Riser optical fiber

raceways and riser cable routing assemblies shall be listed

as having fire-resistant characteristics capable of preventing

the carrying of fire from floor to floor. Cables specified in

770.179(A) through (D) and 770.179(E)(1), that are part of

an electrical circuit protective system, shall be fire-resistive

cable and identified with the protective system number on

the product or on the smallest unit container in which the

product is packaged and installed in accordance with the

listing of the protective system.

(C) General-Purpose Optical Fiber Cable Raceways

and Cable Routing Assemblies. General-purpose optical

fiber cable raceways and cable routing assemblies shall be

listed as being resistant to the spread of fire. (F) Field-Assembled Optical Fiber Cables. Field- assembled optical fiber cable shall comply with

770.179(F)(1) through (4).

(1) The specific combination of jacket and optical fibers

intended to be installed as a field- assembled optical

fiber cable shall be listed in accordance with

770.179(A), (B), or (D) and shall be marked in

accordance with Table 770.179.

(2) The jacket of a field-assembled optical fiber cable shall

have a surface marking indicating the specific optical

fibers with which it is listed for use.

(3) The optical fibers shall have a permanent marking, such

as a marker tape, indicating the jacket with which they

are listed for use.

(4) The jacket without fibers shall meet the listing

requirements for communications raceways in

800.182(A), (B), or (C) in accordance with the cable

marking.



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770.180 Grounding Devices. Where bonding or ground-

ing is required, devices used to connect a shield, a sheath, or non–current-carrying metallic members of a cable to a

bonding conductor or grounding electrode conductor shall

be listed or be part of listed equipment.

Change Description: New section added to address requirements for optical fiber cable grounding devices to be listed or part of listed equipment. Impact(s) : No negative impact.

2

ARTICLE 800

Communication Systems

800.12 Innerduct. Listed plenum communications race-

way, listed riser communications raceway, and listed

general-purpose communications raceway selected in ac-

cordance with the provisions of Table 800.154(b) shall be

permitted to be installed as innerduct in any type of listed

raceway permitted in Chapter 3.

Change Description: Added a new definition addressing use of raceways as an innerduct in communication systems. Impact(s) : No negative impact.

2

800.24 Mechanical Execution of Work. Communications

circuits and equipment shall be installed in a neat and

workmanlike manner. Cables installed exposed on the sur-

face of ceilings and sidewalls shall be supported by the

building structure in such a manner that the cable will not

be damaged by normal building use. Such cables shall be

secured by hardware, including straps, staples, cable ties,

hangers, or similar fittings designed and installed so as not

to damage the cable. The installation shall also conform to

300.4(D) and 300.11. Nonmetallic cable ties and other non-

metallic cable accessories used to secure and support cables

in other spaces used for environmental air (plenums) shall

be listed as having low smoke and heat release properties.


2



containing communications entrance wire or cable shall be

connected by a bonding conductor or grounding electrode

Change Description: Moved the definition containing a requirement to a new section to comply with NEC Style Manual.

1



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conductor to a grounding electrode in accordance with

800.100(B).



Communications Wires and Cables. (A) Types of Raceways. Communications wires and

cables shall be permitted to be installed in any raceway that

complies with either (A)(1) or (A)(2) and in cable routing

assemblies installed in compliance with 800.110(C).

(C) Cable Routing Assemblies. Communications wires

and cables shall be permitted to be installed in plenum

cable routing assemblies, riser cable routing assemblies,

and general-purpose cable routing assemblies selected in

accordance with the provisions of 800.113 and installed in

accordance with 800.110(C)(1) and (2).










Change Description: This added subsection provides installation rules for cable routing assemblies. Impact(s) : No negative impact.

2

800.113 Installation of Communications Wires, Cables

and Raceways, and Cable Routing Assemblies. Installa-

tion of communications wires, cables and raceways, and

cable routing assemblies shall comply with 800.113(A)

through (L). Installation of raceways and cable routing as-

semblies shall also comply with 800.110.

(A) Listing. Communications wires, communications

cables, communications raceways, and racewayscable rout-

ing assemblies installed in buildings shall be listed.


nums). The following wires, cables, and raceways shall be

Change Description: Expanded scope of the section to include cable routing assemblies. Impact(s) : No negative impact.

2



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permitted in other spaces used for environmental air as

described in 300.22(C):

(7) Types CMP, CMR, CMG, CM, and CMX cables in-

stalled in plenum communications raceways, riser com-

munications raceways, and general-purpose communi-

cations raceways supported by solid bottom metal

cable trays with solid metal covers in other spaces used

for environmental air (plenums) as described in

300.22(C)

(D) Risers — Cables and Raceways in Vertical Runs.

The following cables, raceways, and raceways cable rout-

ing assemblies shall be permitted in vertical runs penetrat-

ing one or more floors and in vertical runs in a shaft:

(3) Plenum and riser cable routing assemblies

(F) Risers — Cables, Raceways, and RacewaysCable

Routing Assemblies in Fireproof Shafts. The following

cables, raceways, and raceways cable routing assemblies shall

be permitted to be installed in fireproof riser shafts having

firestops at each floor:

(3) Plenum, riser, and general-purpose cable routing as-

semblies

800.154 Applications of Listed Communications Wires,

Cables and Raceways, and Listed Cable Routing Assem-

blies. Permitted and nonpermitted applications of listed

communications wires, cables, and raceways, and listed cable

routing assemblies, shall be in accordance with one of the

following:

(1) Listed communications wires and cables as indicated in

Table 800.154(a).

(2) Listed communications raceways as indicated in Table

800.154(b)

(3) Listed cable routing assemblies as indicated in Table

800.154(c)

Change Description: Expanded scope of the section to include cable routing assemblies. Impact(s) : No negative impact.

2

800.170 Equipment. Communications equipment shall be

listed as being suitable for electrical connection to a com-

munications network.

(C) Plenum Grade Cable Ties. Cable ties intended for

Change Description: Revised to correlate with requirements in NFPA 90A, providing criteria for cable ties and accessories installed in plenums.

2



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use in other space used for environmental air (plenums)

shall be listed as having low smoke and heat release prop-

erties.

G) Communications Circuit Integrity (CI) Cables or

Electrical Circuit Protective System. Cables suitable for

use in communications systems to ensure that are used for

survivability of critical circuits during a specified time un-

der fire conditions shall be listed as circuit integrity (CI)

cable. Cables identified in 800.179(A) through (E) that and

meet the requirements for circuit integrity shall have the

additional classification using the suffix “CI.”either

800.179(G)(1) or (2) as follows:

(1) Circuit Integrity (CI) Cables. Circuit integrity (CI)

cables specified in 800.179(A) through (E), and used for


classification using the suffix “CI.” In order to maintain its

listed fire rating, circuit integrity (CI) cable shall only be

installed in free air.

(2) Fire-Resistive Cables. Cables specified in 800.179(A)

through (E) and 800.179(G)(1), that are part of an electrical

circuit protective system, shall be fire-resistive cable iden-

tified with the protective system number on the product, or

on the smallest unit container in which the product is pack-

aged, and shall be installed in accordance with the listing of

the protective system.

Also, the change in subsection (G) separates the two methods of establishing cable survivability. Cable are either tested as a CI cable or tested as part of an electrical circuit protective system. The new text clarifies the two cable options and marking requirements. Impact(s) : No negative impact.


ing is required, devices used to connect a shield, a sheath,

or non–current-carrying metallic members of a cable to a

bonding conductor or grounding electrode conductor shall


(A) Plenum Communications Raceways and Plenum

Cable Routing Assemblies. Plenum communications race-

ways and plenum cable routing assemblies listed as plenum

optical fiber raceways shall be permitted for use in ducts,

plenums, and other spaces used for environmental air and

shall also be listed as having adequate fire-resistant and low

smoke-producing characteristics.

Change Description: New section added to address requirements for communication circuits grounding devices to be listed or part of listed equipment. Impact(s) : No negative impact.

2



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ARTICLE 810

Radio and Television Equipment 810.6 Antenna Lead-In Protectors. Where an antenna

lead-in surge protector is installed, it shall be listed as being

suitable for limiting surges on the cable that connects the

antenna to the receiver/transmitter electronics and shall be

connected between the conductors and the grounded shield

or other ground connection. The antenna lead-in protector

shall be grounded using a bonding conductor or grounding

electrode conductor installed in accordance with 810.21(F).

Change Description: Antenna lead-in protectors may be subject to high energy lightning surges in the range of 5-50 kA or higher. Listing and compliance with appropriate requirements ensure that the protector can withstand these surges without introducing a risk of fire or personal injury (from explosions) and also that the protector will continue to provide surge protection after being subjected to various environmental and surge conditions that may be expected in an typical installation. Impact(s) : Improves safety - no negative impact.

2

810.7 Grounding Devices. Where bonding or grounding is

required, devices used to connect a shield, a sheath, non–

current-carrying metallic members of a cable, or metal

parts of equipment or antennas to a bonding conductor or

grounding electrode conductor shall be listed or be part of

listed equipment.

Change Description: New section added to address requirements for Radio and television equipment grounding devices to be listed or part of listed equipment. Impact(s) : No negative impact.

2

ARTICLE 820 Community Antenna Television and Radio Distribution Systems

820.3 Other Articles. Circuits and equipment shall com-

ply with 820.3(A) through (G).(J).

(B) Wiring in Ducts for Dust, Loose Stock, or Vapor Removal. The requirements of 300.22(A) shall apply. (C) Equipment in Other Space Used for Environmental

Air. The requirements of 300.22(C)(3) shall apply.

Change Description: Added references to Section 300.22 for community antenna television and radio distribution wiring systems installed in ducts and other spaces used for environmental air. Impact(s) : No negative impact.

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820.24 Mechanical Execution of Work. Community tele-

vision and radio distribution systems shall be installed in a

neat and workmanlike manner. Coaxial cables installed ex-

posed on the surface of ceiling and sidewalls shall be sup-

ported by the building structure in such a manner that the

cables will not be damaged by normal building use. Such

cables shall be secured by hardware including straps,

staples, cable ties, hangers, or similar fittings designed and

installed so as not to damage the cable. The installation

shall also conform to 300.4(D) and 300.11. Nonmetallic

cable ties and other nonmetallic cable accessories used to

secure and support cables in other spaces used for environ-

mental air (plenums) shall be listed as having low smoke

and heat release properties.


2

820.47 Underground Coaxial Cables Entering Build-

ings. Underground coaxial cables entering buildings shall

comply with 820.47(A) and (B).

(A) Underground Systems with Electric Light and

Power, Power, Class 1, or Non–Power-Limited Fire

Alarm Circuit Conductors. Underground coaxial cables

in a duct, pedestal, handhole enclosure, or manhole that

contains electric light, power, or power conductorsClass 1

or Class 1 circuitsnon–power-limited fire alarm circuit con-

ductors shall be in a section permanently separated from

such conductors by means of a suitable barrier.

Change Description: This change addresses non-power-limited fire alarm circuits missing from this section. Impact(s) : No negative impact.

2



containing entrance coaxial cable shall be connected by a

bonding conductor or grounding electrode conductor to a

grounding electrode in accordance with 820.100(B).


1

820.100 Cable Bonding and Grounding. The shield of

the coaxial cable shall be bonded or grounded as specified

in 820.100(A) through (D).

Change Description: Correlates with similar requirements in Articles 770, 800, and 830, not allowing the use of steam or hot water pipes as

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(3) In Buildings or Structures Without an Intersystem

Bonding Termination or Grounding Means. If the build-

ing or structure served has no intersystem bonding termi-

nation or grounding means, as described in 820.100(B)(2),

the grounding electrode conductor shall be connected to

either of the following:

(2) If the building or structure served has no intersystem

bonding termination or grounding means, as described

in 820.100(B)(2) or (B)(3)(1), to any one of the indi-

vidual grounding electrodes described in 250.52(A)(5),

(A)(7), and (A)(8). Steam or hot water pipes or air

terminal conductors (lightning-rod conductors) shall

not be employed as grounding electrodes for bonding

conductors or grounding electrode conductors.

grounding electrodes. Impact(s) : No negative impact.


Coaxial Cables.

(C) Cable Routing Assemblies. Coaxial cables shall be

permitted to be installed in plenum cable routing assem-

blies, riser cable routing assemblies, and general-purpose

cable routing assemblies selected in accordance with the

provisions of 800.113 and installed in accordance with

820.110(C)(1) and (2).





tween supports exceed 3 m (10 ft)





Change Description: This added subsection provides installation rules for cable routing assemblies. Impact(s) : No negative impact.

2

820.113 Installation of Coaxial Cables. Installation of co-

axial cables shall comply with 820.113(A) through (K).

Installation of raceways shall comply with 820.110.



Change Description: This change establishes listing requirements for community antenna television and radio distribution system cables installed in other spaces used for environmental air (plenums).

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300.22(C):

(6) Types CATVP, CATVR, CATV, and CATVX cables in-

stalled in plenum communications raceways, riser com-

munications raceways, or general-purpose communica-

tions raceways supported by solid bottom metal cable trays

with solid metal covers in other spaces used for

environmental air (plenums) as described in 300.22(C)





bonding conductor, or grounding electrode conductor, shall


Change Description: New section added to address requirements for community antenna television and radio distribution system equipment grounding devices to be listed or part of listed equipment. Impact(s) : No negative impact.

2

ARTICLE 830 Network-Powered Broadband Communications Systems

830.3 Other Articles. Circuits and equipment shall com-

ply with 830.3(A) through (F).(G).

B) Wiring in Ducts for Dust, Loose Stock, or Vapor

Removal. The requirements of 300.22(A) shall apply.

Change Description: Added references to Section 300.22 for network-powered broadband communication wiring systems installed in ducts for dust, loose stock, or vapor removal. Impact(s) : No negative impact.

2

830.24 Mechanical Execution of Work. Network-

powered broadband communications circuits and equip-

ment shall be installed in a neat and workmanlike manner.

Cables installed exposed on the surface of ceilings and

sidewalls shall be supported by the building structure in

such a manner that the cable will not be damaged by nor-

mal building use. Such cables shall be secured by hardware

including straps, staples, cable ties, hangers, or similar fit-

tings designed and installed so as not to damage the cable.

The installation shall also conform to 300.4(D) and 300.11.

Nonmetallic cable ties and other nonmetallic cable acces-


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sories used to secure and support cables in other spaces

used for environmental air (plenums) shall be listed as hav-

ing low smoke and heat release properties.



containing network-powered broadband communications

entrance cable shall be connected by a bonding conductor

or grounding electrode conductor to a grounding elec-

trode in accordance with 830.100(B).


1

830.110 Raceways for Low- and Medium-Powerand

Cable Routing Assemblies for Network-Powered Broad-

band Communications Cables.

(A) Types of Raceways. Low-power network-powered

broadband communications cables shall be permitted to be

installed in any raceway that complies with either

830.110(A)(1) or (A)(2) and in cable routing assemblies

installed in compliance with 830.110(C). Medium-power

network-powered broadband communications cables shall

be permitted to be installed in any raceway that complies

with 830.110(A)(1).

(2) Communications Raceways. Low-power network-

powered broadband communications cables shall be per-

mitted to be installed in listed plenum communications

raceways, listed riser communications raceways, and listed

general-purpose communications raceways, selected in ac-

cordance with the provisions of 800.113 and 830.113 and

installed in accordance with 362.24 through 362.56, where

the requirements applicable to electrical nonmetallic tubing

apply.

Change Description: The change corrects an oversight in the 2011 NEC. Table 830.154(a) and 830.113 permit low-power network-powered communications cables to be installed in communications raceways, but communications raceways were omitted from this section. Impact(s) : No negative impact.

1

830.110 Raceways for Low- and Medium-Powerand

Cable Routing Assemblies for Network-Powered Broad-

band Communications Cables.

(C) Cable Routing Assemblies. Network-powered broad-

Change Description: This added subsection provides installation rules for cable routing assemblies.

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band communications cables shall be permitted to be in-

stalled in plenum cable routing assemblies, riser cable rout-

ing assemblies, and general-purpose cable routing

assemblies selected in accordance with the provisions of

800.113 and installed in accordance with 830.110(C)(1)

and (2).











830.113 Installation of Network-Powered Broadband

Communications Cables. Installation of network-powered

broadband communications cables shall comply with

830.113(A) through (H).




300.22(C):

(6) Types BLP, BMR, BLR, BM, BL, and BLX cables

installed in plenum communications raceways, riser

communications raceways, or general-purpose commu-

nications raceways supported by solid bottom metal

cable trays with solid metal covers in other spaces used

for environmental air (plenums) as described in

300.22(C)

Change Description: This change establishes listing requirements for network-powered broadband communication cables installed in other spaces used for environmental air (plenums). Impact(s) : No negative impact.

2






Change Description: New section added to address requirements for network-powered broadband communication cables grounding devices to be listed or part of listed equipment. Impact(s) :

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No negative impact.

ARTICLE 840 Premises-Powered Broadband Communications Systems

840.3 Other Articles.

(B) Cables in Ducts for Dust, Loose Stock, or Vapor

Removal. The requirements of 300.22(A) for wiring sys-

tems shall apply to conductive optical fiber cables.

(D) Installation and Use. The requirements of 110.3(B)

shall apply.

Change Description: Added new subsection to provide requirements for optical fiber cables, similar to Section 800.3. Impact(s) : No negative impact.

2

840.49 Metallic Entrance Conduit Grounding. The re-

quirements of 770.49 shall apply. Change Description: Added reference to Section 770.49 for metallic entrance conduit grounding. Impact(s) : No negative impact.

2

840.93 Grounding or Interruption. Non–current-carrying

metallic members of optical fiber cables, communications

cables, or coaxial cables entering buildings or attaching to

buildings shall comply with 840.93(A), (B), or (C), respec-

tively.

Change Description: Editorial change, consistent with NEC Style Manual. Impact(s) : No negative impact.

1

840.103 Equipment Grounding. The grounding of the

ONT shall be as required by the equipment listing.

Change Description: Deleted redundant section – grounding requirements are covered 840.101(C). Impact(s) : No negative impact.

1






Change Description: New section added to address requirements for premises-powered broadband communication cables grounding devices to be listed or part of listed equipment.

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CHAPTER 9 Tables

Table 1 Percent of Cross Section of Conduit and Tubing for

Conductors and Cables

Notes to Tables (6) For combinations of conductors of different sizes, use

actual dimensions or Table 5 and Table 5A for dimen-

sions of conductors and Table 4 for the applicable con-

duit or tubing dimensions.

Change Description: Since not all conductor sizes are covered in the referenced tables, the code was changed to allow use of actual dimensions of the conductors in calculating conduit and tubing fill. Impact(s) : No negative impact.

2



Notes to Tables (7) When calculating the maximum number of conductors or

cables permitted in a conduit or tubing, all of the same

size (total cross-sectional area including insulation), the

next higher whole number shall be used to determine the

maximum number of conductors permitted when the cal-

culation results in a decimal of 0.8 or larger.greater than

or equal to 0.8. When calculating the size for conduit or

tubing permitted for a single conductor, one conductor

shall be permitted when the calculation results in a deci-

mal greater than or equal to 0.8.

Change Description: Editorial change. Impact(s) : No negative impact.

1



Notes to Tables (10) The values for approximate conductor diameter and area

shown in Table 5 are based on worst-case scenario and

indicate round concentric-lay-stranded conductors. Solid

and round concentric-lay-stranded conductor values are

grouped together for the purpose of Table 5. Round

compact-stranded conductor values are shown in Table

5A. If the actual values of the conductor diameter and

Change Description: Added a new note clarifying the data provided in Tables 5 and 5A. Impact(s) : No negative impact.

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area are known, they shall be permitted to be used.

EFCOG Best Practice #178

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Transcript of EFCOG Best Practice #178