NEC Code-Making Panel 3 Second Draft Meeting Agenda November 2-7, 2015 San Diego, CA ...

264 Pages·2015·9.37 MB·English

National Fire Protection Association
1 Batterymarch Park, Quincy, MA 02169-7471
Phone: [phone] • Fax: [phone] • www.nfpa.org

NEC Code-Making Panel 3

Second Draft Meeting Agenda

November 2-7, 2015

San Diego, CA

Item No. Subject

15-11 -1 Call to Order

15-11-2 Introduction of Members and Guests

15-11-3 Approval of A2016 First Draft Meeting Minutes

15-11-4 Review of Meeting Procedures and Revision Schedule

15-11-5 Task Group Reports

15-11-6 Process Public Comments and Develop Second Revisions

15-11-7 Fire Protection Research Foundation Requests

15-11-8 Old Business

15-11-9 New Business

15-11-10 Adjournment
Public Comment No. 1063 Global Input Lawrence Ayer
Public Comment No. 462 Section No. 300.4 ROBERT JENSEN
Public Comment No. 1028 Section No. 300.4  Christel Hunter
Public Comment No. 1165 Section No. 300.4(B) james dorsey
Public Comment No. 1425 Section No. 300.5(A) submitted
Public Comment No. 1219 Section No. 300.5(D)(3) Marcelo Hirschler
Public Comment No. 1392 Section No. 300.5(D)(3) submitted
Public Comment No. 1395 Section No. 300.5(D)(3) submitted
Public Comment No. 970 Section No. 300.5(D)(4) WILLIAM NOACK
Public Comment No. 99 Section No. 300.7(B) DAVID KENDALL
Public Comment No. 1641 Section No. 300.9 submitted
Public Comment No. 1657 Section No. 300.11 submitted
Public Comment No. 879 Section No. 300.11 Marcelo Hirschler
Public Comment No. 122 Section No. 300.11(B)(1) Aaron Adamczyk
Public Comment No. 801 Section No. 300.11(B)(1) Marcelo Hirschler
Public Comment No. 498 Section No. 300.12 Phil Simmons
Public Comment No. 1151 Section No. 300.19(A) Christel Hunter
Public Comment No. 580 Section No. 300.20(B) Carl Johnson II
Public Comment No. 1788 Section No. 300.22(B) submitted
Public Comment No. 163 Section No. 300.22(C)(3) Aaron Adamczyk
Public Comment No. 555 Section No. 300.3(B)(1) ALFIO TORRISI
Public Comment No. 108 Section No. 300.37 CARL JOHNSON II
Public Comment No. 113 Section No. 300.37 CARL JOHNSON II
Public Comment No. 115 Section No. 300.37 CARL JOHNSON II
Public Comment No. 1472 Section No. 300.37 submitted
Public Comment No. 1496 Section No. 300.37 submitted
Public Comment No. 246 Section No. 300.37 Matt Szabo
Public Comment No. 416 Section No. 300.37 John Bogart
Public Comment No. 826 Section No. 590.4(G) James Dollard
Public Comment No. 1143 Section No. 590.4(J) LORI WEIDNER
Public Comment No. 615 Section No. 590.6(B) NEHAD EL‐SHERIF
Public Comment No. 691 Section No. 725, Part IV. Terry Peters
Public Comment No. 969 Section No. 725.1 Randall Wright
Public Comment No. 460 Section No. 725.3(C) ROBERT JENSEN
Public Comment No. 1397 Section No. 725.3(K) submitted
Public Comment No. 1677 Section No. 725.24 submitted
Public Comment No. 74 Section No. 725.24 DAVID KIDDOO
Public Comment No. 602 Section No. 725.121(A) Stanley Kaufman
Public Comment No. 689 Section No. 725.133 Terry Peters
Public Comment No. 447 Sections 725.135(K), 725.135(L), 725.ROBERT JENSEN
Public Comment No. 1423 Section No. 725.135(A) submitted
Public Comment No. 223 Section No. 725.135(K) DAVID KIDDOO
Public Comment No. 224 Section No. 725.135(L) DAVID KIDDOO
Public Comment No. 225 Section No. 725.135(M) DAVID KIDDOO
Public Comment No. 1689 Section No. 725.143 submitted
Public Comment No. 692 Section No. 725.143 Terry Peters
Public Comment No. 688 Section No. 725.179 Terry Peters
Public Comment No. 866 Section No. 725.179(B) Marcelo Hirschler
Public Comment No. 454 Section No. 760.3(B) ROBERT JENSEN
Public Comment No. 75 Section No. 760.24(A) DAVID KIDDOO
Public Comment No. 1685 Section No. 760.24(A) submitted
Public Comment No. 1429 Section No. 760.135(A) submitted
Public Comment No. 461 Section No. 760.176  ROBERT JENSEN
Public Comment No. 869 Section No. 760.176(D) Marcelo Hirschler
Public Comment No. 450 Section No. 760.179(C) ROBERT JENSEN
Public Comment No. 870 Section No. 760.179(E) Marcelo Hirschler
National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...
Public Comment No. 1063-NFPA 70-2015 [ Global Input ]
Article 100 Definitions
Voltage, Nominal…..
Informational Note No. 3: Certain 48-volt DC battery units have a charging float voltage up to 58 volts. In DC
applications 60 volts is used to cover the entire range of float voltages.
Article 110
110.27 Guarding of Live Part
(A) Live Parts Guarded Against Accidental Contact. Except as elsewhere required or permitted by this Code, live parts of
electrical equipment operating at 50 volts AC/60 volts DCor more shall be guarded against accidental contact by approved
enclosures or by any of the following means:
Article 200 Use and Identification of Grounded Conductors
200.7
(B) Circuits of Less Than 50 VoltsAC. A conductor with white or gray color insulation or three continuous white stripes or
having a marking of white or gray at the termination for circuits of less than 50 volts ACshall be required to be grounded only as
required by 250.20(A).
C) Circuits of 50 Volts AC or More. The use of insulation that is white or gray or that has three continuous white or gray stripes
for other than a grounded conductor for circuits of 50 volts ACor more shall be permitted only as in (1) and (2).
Article 215 Feeders
215.12(C)(2) Feeders Supplied from Direct-Current Systems.
Where a feeder is supplied from a dc system operating at more than 50 60 volts, each ungrounded conductor of 4 AWG or
larger shall be identi?ed 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 identi?ed by polarity at all termination,
connection, and splice points in compliance with 215.12(C)(2)(a) and (b). The identi?cation methods utilized for
conductors originating within each feeder panelboard or similar feeder distribution equipment shall be documented in
a manner that is readily available or shall be permanently posted at each feeder panelboard or similar feeder
distribution equipment.
Article 430 Motors, Motor Circuits, and Controllers
430.232 Where Required. Exposed live parts of motors and controllers operating at 50 volts DCor more between terminals
shall be guarded against accidental contact by enclosure or by location as follows:
430.233 Guards for Attendants. Where live parts of motors or controllers operating at over 50 volts ACto ground are guarded
against accidental contact only by location as specified in 430.232, and where adjustment or other attendance may be
necessary during the operation of the apparatus, suitable insulating mats or platforms shall be provided so that the attendant
cannot readily touch live parts unless standing on the mats or platforms.
Article 445 Generators
445.14 Protection of Live Parts. Live parts of generators operated at more than 50 volts AC/60 volts DCto ground shall not
be exposed to accidental contact where accessible to unquali?ed persons.
Article 460 Capacitors
460.6(A) Time of Discharge. The residual voltage of a capacitor shall be reduced to 50 volts DC , nominal, or less within 1
minute after the capacitor is disconnected from the source of supply.
460.28(A) Means for Discharge. A means shall be provided to reduce the residual voltage of a capacitor to 50 volts DCor less
within 5 minutes after the capacitor is disconnected from the source of supply.
Article 480 Storage Batteries
480.5 Overcurrent Protection for Prime Movers. Overcurrent protection shall not be required for conductors from a battery
with a nominal voltage of 60 volts DC or less if the battery provides power for starting, ignition, or control of prime
movers. Section 300.3 shall not apply to these conductors.
480.6 DC Disconnect Methods. (A) Disconnecting Means. A disconnecting means shall be provided for all ungrounded
conductors derived from a stationary battery system with a nominal voltage over 60 volts DC. A disconnecting means
shall be readily accessible and located within sight of the battery system.
Article 522 Control Systems for Permanent Amusement Attractions
522.25 Ungrounded Control Circuits. Separately derived ac and 2-wire dc circuits and systems 50 volts AC/60 volts DCor
greater shall be permitted to be ungrounded, provided that all the following conditions are met:
Article 625
625.18 Interlock. Electric vehicle supply equipment shall be provided with an interlock that de-energizes the electric
vehicle connector whenever the electrical connector is uncoupled from the electric vehicle. An interlock shall not be
required for portable cord-and-plug-connected electric vehicle supply equipment intended for connection to
1 of 2079 10/1/2015 11:02 AM
National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...
receptacle outlets rated at 125 volts, single phase, 15 and 20 amperes. An interlock shall not be required for dc
supplies less than5060volts dc.
625.19 Automatic De-Energization of Cable. The electric vehicle supply equipment or the cable-connector
combination of the equipment shall be provided with an automatic 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 5060volts dc.
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 non-locking, 2-pole,3-wire grounding-type receptacle outlets rated at 125 V, single phase, 15 and 20 amperes
or from a supply of less than 5060 volts dc.
(4) Supply Circuits. The supply circuit to the mechanical ventilation equipment shall be electrically interlocked with
the electric vehicle supply equipment and shall remain energized during the entire electric vehicle charging cycle.
Electric vehicle supply equipment shall be marked in accordance with625.15. Electric vehicle supply equipment
receptacles rated at 125 volts, single phase, 15 and 20 amperes shall be marked in accordance with 625.15 and
shall be switched, and the mechanical ventilation system shall be electrically interlocked through the switch supply
power to the receptacle. Electric vehicle supply equipment supplied from less than5060 volts dc shall be marked in
accordance with 625.15(C) and shall be switched, and the mechanical ventilation system shall be electrically
interlocked through the switch supply power to the electric vehicle supply equipment.
Article 669 Electroplating
669.6 Wiring Methods. Conductors connecting the electrolyte tank equipment to the conversion equipment shall be
in accordance with 669.6(A) and (B).
(A) Systems Not Exceeding 5060Volts Direct Current. Insulated conductors shall be permitted to be run without insulated
support, provided they are protected from physical damage. Bare copper or aluminum conductors shall be permitted where
supported on insulators.
(B) Systems Exceeding 50 60 Volts Direct Current. Insulated conductors shall be permitted to be run on insulated
supports, provided they are protected from physical damage. Bare copper or aluminum conductors shall be permitted
where supported on insulators and guarded against accidental contact up to the point of termination in accordance
with 110.27.
Article720 Circuits and Equipment Operating at Less than 50 Volts
Circuits and Equipment Operating at Less Than 50 Volts AC/60 Volts DC.
720.1 Scope. This article covers installations operating at less than 50 volts, alternating current, or 60 voltsdirectcurrentor
alternating current.
720.11 Mechanical Execution of Work.Circuits operating at less than 50 voltsAC or 60 volts DCshall be installed
in a neat and workmanlike manner. Cables shall be supported by the building structure in such a manner that the
cable will not be damaged by normal building use.Type your content here ...
Statement of Problem and Substantiation for Public Comment
Over the past decade numerous code articles have been placed into the NEC as a result of the increased resurgence of DC systems.
These systems, similar to their AC counterpart, have mandated code requirements that must be met when the system voltage exceeds
a certain threshold. For years the system threshold for many of the requirements has been kept at the 50 volt level. While this is
appropriate for AC systems, it can create confusion to the user of the document when applied to a 48 DC batteries during charging
where a “float voltage” is common at 58 volts. The float voltage can vary significantly depending on battery chemistry, battery
construction, and the actual ambient temperature. This voltage may be constant for the entire duration of the charge or can fluctuate.
Some 48 volt DC systems stay above the 50 volt threshold for 99% of the time for applications such as telecommunications, UPS
systems and emergency lighting.
This elevated voltage may create confusion since various AHJ’s might see 58 volts and mandate that a code rule must be followed
since the 50 volt threshold has been increased. To resolve these issues a DC task group was formed to research the DC systems
found in the NEC and to correlate the various DC topics that were being added to the NEC. The task group recommended the use of
60 volt DC throughout the code to eliminate the confusion that could arise from the elevated float voltage. The intent of the task group
was to provide a consistent use of the voltage threshold within the NEC document.
For the 2017 NEC Revision Cycle, a task group was formed to correlate the use of the 50/60V threshold and provide public comments
for the second draft. The task group members Larry Ayer (Chair), Bill Cantor, Donny Cook, Jim Dollard (Co-Chair), John Kovacik (DC
Task Group Chair), Ernie Gallo, Vince Saporita, and Jim White provided input and guidance for these recommendations.
To correlate the use of 50 volts for AC systems and 60 volts for DC systems, the recommended NEC changes are based on the
following:
2 of 2079 10/1/2015 11:02 AM
National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...
1. Where a code section refers to AC systems only and indicates 50 volts the acronym “AC” was added to provide clarity.
2. Where a code section refers to a requirement used only in a DC system at a 50 volt threshold, the voltage is revised to 60 volts and
the term “DC” is added
3. Where a code section indicates a 50 volt threshold, and the section is a requirement for both AC and DC systems, the text is revised
as “50 volts AC/60 volts DC”.
4. When a code section refers to DC systems, and the term “nominal” is used, it will be deleted since the voltage threshold is increased
to 60 volts.
5. A fine print note is being recommended in Article 100 below the definition for “Nominal Voltage” to provide additional information on
float voltage.
NEC changes are being recommended for the following code sections:
1. *Add informational note after “Voltage, Nominal”. Informational note to read as follows:*
*Informational Note No. 3: Certain 48-volt DC battery units use a charging float voltage up to 58 volts. In DC applications 60 volts is
used to cover the entire range of float voltages.*
2. For section 110.27, “50 volts” is being changed to “50 volts AC/60 volts DC”. This will clarify the voltage threshold for AC and DC
systems.
3. Section 200.7 (B) and (C) applies to conductor marking for AC systems only. “AC” is added after 50 volts to clarify that this
requirement is only for AC systems.
4. Section 210.5(C)(2) was revised in the First draft that changed “50 volts” to “60 volts” to correlate with the new microgrid article.
Revise section 215.12(C) from“50 volts” to “60 volts” to correlate with section 210.5(C)(2).
5. In section 445.14, revise “50 volts” to 50 volts AC/60 volts DC” to clarify that this requirement pertains to both AC and DC systems.
6. In sections 480.5 and 480.6 “50 volts” was changed to “60 volts” since these pertain to DC batteries and DC systems.
7. In section 522.25, “50 volts” is being changed to “50 volts AC / 60 volts DC” to clarify that this section pertains to both AC and DC
systems and distinguishes between the two voltage systems and thresholds.
8. Article 625, Electrical Vehicle Charging System. Revise the text from “50 volts” to“60 volts” since these are DC systems.
9. Section 669.6(A) and (B) are DC systems. Revise the text from“50 volts” to “60 volts”
10. Section 690.71 (B) is a DC system with a threshold of 50 volts. Revise the text from “50 volts” to “60 volts DC”.
11. Article 720 Circuits and Equipment Operating at Less Than 50 Volts covers both AC and DC systems. To correlate the Title has
been changed to “50 Volts AC/60 Volts DC”. The Scope 720.1 and section 720.11 have been modified to clarify that this Article applies
to both systems with the corresponding voltage.
Related Item
Public Input No. 3681-NFPA 70-2014 [Global Input]
Submitter Information Verification
Submitter Full Name:Lawrence Ayer
Organization: Biz Com Electric, Inc.
Affilliation: IEC
Street Address:
City:
State:
Zip:
Submittal Date: Wed Sep 23 14:39:50 EDT 2015
3 of 2079 10/1/2015 11:02 AM
National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...
Public Comment No. 462-NFPA 70-2015 [ Section No. 300.4 ]
300.4 Protection Against Physical Damage.
Where subject to physical damage, conductors, raceways, and cables shall be protected.
(A) Cables and Raceways Through Wood Members.
(1) Bored Holes.
In both exposed and concealed locations, where a cable- or raceway-type wiring method is installed through bored holes in
1
joists, rafters, or wood members, holes shall be bored so that the edge of the hole is not less than 32 mm (1 ⁄4 in.) from the
nearest edge of the wood member. Where this distance cannot be maintained, the cable or raceway shall be protected from
penetration by screws or nails by a listed and marked steel plate(s) or bushing(s)
, at least 1.6 mm ( 1⁄16 in.) thick, and
of appropriate length and width installed to cover the area of the wiring.
Exception No. 1: Steel plates shall not be required to protect rigid metal conduit, intermediate metal conduit, rigid
nonmetallic conduit, or electrical metallic tubing.
Exception No. 2: A listed and marked steel plate less than 1.6 mm ( 1⁄16 in.) thick that provides equal or better protection
against nail or screw penetration shall be permitted.
Informational Note: ANSI/UL 2239 defines requirements for listed steel bushings.
(2) Notches in Wood.
Where there is no objection because of weakening the building structure, in both exposed and concealed locations, cables or
raceways shall be permitted to be laid in notches in wood studs, joists, rafters, or other wood members where the cable or
raceway at those points is protected against nails or screws by a listed and marked steel plate at least 1.6 mm ( 1⁄16 in.)
thick, and of appropriate length and width, installed to cover the area of the wiring. The steel plate shall be installed before the
building finish is applied.
Exception No. 1: Steel plates shall not be required to protect rigid metal conduit, intermediate metal conduit, rigid nonmetallic
conduit, or electrical metallic tubing. Exception No. 2: A listed and marked steel plate less than 1.6 mm
(
1⁄16 in.) thick that provides equal or better protection against nail or screw penetration shall be permitted.
(B) Nonmetallic-Sheathed Cables and Electrical Nonmetallic Tubing Through Metal Framing Members.
(1) Nonmetallic-Sheathed Cable.
In both exposed and concealed locations where nonmetallic-sheathed cables pass through either factory- or field-punched, cut,
or drilled slots or holes in metal members, the cable shall be protected by listed bushings or listed grommets covering all metal
edges that are securely fastened in the opening prior to installation of the cable.
(2) Nonmetallic-Sheathed Cable and Electrical Nonmetallic Tubing.
Where nails or screws are likely to penetrate nonmetallic-sheathed cable or electrical nonmetallic tubing, a listed and marked
1
steel sleeve, steel plate, or steel clip not less than 1.6 mm ( ⁄16 in.) in thickness shall be used to protect the cable or
tubing. Exception: A listed and marked steel plate less than 1.6 mm
(
1
⁄16 in.) thick that provides equal or better protection against nail or screw penetration shall be permitted.
(C) Cables Through Spaces Behind Panels Designed to Allow Access.
Cables or raceway-type wiring methods, installed behind panels designed to allow access, shall be supported according to their
applicable articles.
504 of 2079 10/1/2015 11:02 AM
National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...
(D) Cables and Raceways Parallel to Framing Members and Furring Strips.
In both exposed and concealed locations, where a cable- or raceway-type wiring method is installed parallel to framing
members, such as joists, rafters, or studs, or is installed parallel to furring strips, the cable or raceway shall be installed and
supported so that the nearest outside surface of the cable or raceway is not less than 32 mm (1 1⁄4in.) from the nearest edge of
the framing member or furring strips where nails or screws are likely to penetrate. Where this distance cannot be maintained,
the cable or raceway shall be protected from penetration by nails or screws by a listed and marked steel plate, sleeve, or
1
equivalent at least 1.6 mm ( ⁄16 in.) thick.
Exception No. 1: Steel plates, sleeves, or the equivalent shall not be required to protect rigid metal conduit, intermediate metal
conduit, rigid nonmetallic conduit, or electrical metallic tubing.
Exception No. 2: For concealed work in finished buildings, or finished panels for prefabricated buildings where such
supporting is impracticable, it shall be permissible to fish the cables between access points. Exception No. 3: A listed and
marked steel plate less than 1.6 mm
(
1⁄16 in.) thick that provides equal or better protection against nail or screw penetration shall be permitted.
(E) Cables, Raceways, or Boxes Installed in or Under Roof Decking.
A cable, raceway, or box, 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 (1 1⁄2in.) measured from the lowest surface of the roof decking to the
top of the cable, raceway, or box. A cable, raceway, or box shall not be installed in concealed locations in metal-corrugated,
sheet decking–type roof.
Informational Note: Roof decking material is often repaired or replaced after the initial raceway or cabling and roofing
installation and may be penetrated by the screws or other mechanical devices designed to provide “hold down” strength
of the waterproof membrane or roof insulating material.
Exception: Rigid metal conduit and intermediate metal conduit shall not be required to comply with 300.4(E).
(F) Cables and Raceways Installed in Shallow Grooves.
Cable- or raceway-type wiring methods installed in a groove, to be covered by wallboard, siding, paneling, carpeting, or similar
1
finish, shall be protected by 1.6 mm ( ⁄16 in.) thick a listed and marked steel plate, sleeve, or equivalent or by not less than
32-mm (1 1⁄4-in.) free space for the full length of the groove in which the cable or raceway is installed.
Exception No. 1: Steel plates, sleeves, or the equivalent shall not be required to protect rigid metal conduit, intermediate metal
conduit, rigid nonmetallic conduit, or electrical metallic tubing. Exception No. 2: A listed and marked steel plate less than 1.6
mm
(
1
⁄16 in.) thick that provides equal or better protection against nail or screw penetration shall be permitted.
(G) Insulated Fittings.
Where raceways contain 4 AWG or larger insulated circuit conductors, and these conductors enter a cabinet, a box, an
enclosure, or a raceway, the conductors shall be protected by an identified fitting providing a smoothly rounded insulating
surface, unless the conductors are separated from the fitting or raceway by identified insulating material that is securely
fastened in place.
Exception: Where threaded hubs or bosses that are an integral part of a cabinet, box, enclosure, or raceway provide a
smoothly rounded or flared entry for conductors.
Conduit bushings constructed wholly of insulating material shall not be used to secure a fitting or raceway. The insulating fitting
or insulating material shall have a temperature rating not less than the insulation temperature rating of the installed conductors.
(H) Structural Joints.
A listed expansion/deflection fitting or other approved means shall be used where a raceway crosses a structural joint intended
for expansion, contraction or deflection, used in buildings, bridges, parking garages, or other structures.
Statement of Problem and Substantiation for Public Comment
The Panel 3 response to PI 1592 noted a lack of evaluation of protector plates from several manufacturers. This has now been
addressed. Video is accessible at the link which demonstrates that several NEC-compliant protector plates from different manufacturers
do not stop penetration from self-drilling drywall screws.
https://erico.box.com/s/0uvbl0bqapvj25jht3tazlgayqm6lx7r
If the NEC does not require listing of all protector plates, then there is a safety issue that is not being addressed. Self-drilling drywall
screws easily penetrate 1/16” thick protector plates made from low carbon steel (like they all are). Please watch the linked video which
demonstrates that NEC-compliant protector plates from several manufacturers clearly exhibit poor resistance to penetration. As it
stands today, STP2239 and CANENA withdrew the proposal which had already been accepted to define testing requirements for
protector plates, likely due to pressure from specific manufacturers. Without a listing requirement in the NEC, there is no motivation for
STP2239 to follow through with defining evaluation requirements for all protector plates.
Note that in the video demonstration there is no drywall. Without drywall providing support to the drywall screw, it requires the installer
to use less force to prevent the screw from skipping off the protector plate. Therefore, if drywall was present, the screws would
penetrate in even less time.
505 of 2079 10/1/2015 11:02 AM
National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...
Related Item
Public Input No. 1592-NFPA 70-2014 [Section No. 300.4]
Submitter Information Verification
Submitter Full Name:ROBERT JENSEN
Organization: DBI-TELECOMMUNICATION INFRASTR
Affilliation: BICSI
Street Address:
City:
State:
Zip:
Submittal Date: Fri Aug 28 16:07:34 EDT 2015
506 of 2079 10/1/2015 11:02 AM
National Fire Protection Association Report http://submittals.nfpa.org/TerraViewWeb/ContentFetcher?commentPara...
Public Comment No. 1028-NFPA 70-2015 [ Section No. 300.4 [Excluding any Sub-Sections] ]
Where subject to physical damage, conductors, raceways, and cables shall be protected.
Informational Note: Physical damage is not expected to occur to concealed wiring methods during normal
building operation. Minor damage to a raceway, cable armor or cable insulation does not necessarily
violate the integrity of either the contained conductors or the conductors’ insulation.
Statement of Problem and Substantiation for Public Comment
This informational note provides guidance regarding wiring integrity and physical damage. There are many places in the NEC that refer
to "physical damage", and concealment behind walls in accordance with installation requirements in the NEC protects wiring from
physical damage during normal building operation. Since we have no definition of "physical damage" in the NEC and there have been
instances of inspectors rejecting installations with minor scrapes on wiring methods, the second sentence provides guidance for those
cases.
The panel stated that "The addition of this Informational Note does not provide any valuable information to the user to determine
violation of integrity of the conductors or conductor insulation where damage to the raceway has occurred." This informational note is
not intended to provide such information. It is intended to indicate to users of the code that minor blemishes on a wiring method do not
necessarily mean that the wiring method must be replaced or that it is incapable of functioning. To clarify that, the word "Visible" was
replaced with "Minor" as the first word in the second sentence.
Related Item
Public Input No. 4306-NFPA 70-2014 [Section No. 300.4 [Excluding any Sub-Sections]]
Submitter Information Verification
Submitter Full Name:Christel Hunter
Organization: General Cable
Street Address:
City:
State:
Zip:
Submittal Date: Wed Sep 23 05:57:30 EDT 2015
507 of 2079 10/1/2015 11:02 AM