NFPA 70
National Electrical Code
International Electrical Code® Series
2017
See ALERT
,Copyright © 2016
National Fire Protection Association®
One Batterymarch Park
Quincy, Massachusetts 02169-7471
NFPA, NFPA 70, National Fire Protection Association, National Electrical Code, and NEC
are registered trademarks of the National Fire Protection Association.
IMPORTANT NOTICES AND DISCLAIMERS CONCERNING NFPA® STANDARDS
NOTICE AND DISCLAIMER OF LIABILITY CONCERNING THE USE OF NFPA STANDARDS
NFPA® codes, standards, recommended practices, and guides (“NFPA Standards”), of which the document contained herein
is one, are developed through a consensus standards development process approved by the American National Standards
Institute. This process brings together volunteers representing varied viewpoints and interests to achieve consensus on fire
and other safety issues. While the NFPA administers the process and establishes rules to promote fairness in the development
of consensus, it does not independently test, evaluate, or verify the accuracy of any information or the soundness of any
judgments contained in NFPA Standards.
The NFPA disclaims liability for any personal injury, property or other damages of any nature whatsoever, whether special,
indirect, consequential or compensatory, directly or indirectly resulting from the publication, use of, or reliance on NFPA
Standards. The NFPA also makes no guaranty or warranty as to the accuracy or completeness of any information published
herein.
In issuing and making NFPA Standards available, the NFPA is not undertaking to render professional or other services for or
on behalf of any person or entity. Nor is the NFPA undertaking to perform any duty owed by any person or entity to someone
else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a
competent professional in determining the exercise of reasonable care in any given circumstances.
The NFPA has no power, nor does it undertake, to police or enforce compliance with the contents of NFPA Standards.
Nor does the NFPA list, certify, test, or inspect products, designs, or installations for compliance with this document. Any
certification or other statement of compliance with the requirements of this document shall not be attributable to the NFPA
and is solely the responsibility of the certifier or maker of the statement.
See ALERT
ALERT: THIS STANDARD HAS BEEN MODIFIED BY A TIA OR ERRATA
Users of NFPA codes, standards, recommended practices, and guides (“NFPA Standards”) should be
aware that NFPA Standards may be amended from time to time through the issuance of Tentative Interim
Amendments or corrected by Errata. An official NFPA Standard at any point in time consists of the current
edition of the document together with any Tentative Interim Amendment and any Errata then in effect.
In order to determine whether an NFPA Standard has been amended through the issuance
of Tentative Interim Amendments or corrected by Errata, visit the “Codes & Standards” section on NFPA’s
website. There, the document information pages located at the “List of NFPA Codes & Standards” provide
up-to-date, document-specific information including any issued Tentative Interim Amendments and Errata.
To view the document information page for a specific NFPA Standard, go to
http://www.nfpa.org/docinfo to choose from the list of NFPA Standards or use the search feature to select
the NFPA Standard number (e.g., NFPA 101). The document information page includes postings of all
existing Tentative Interim Amendments and Errata. It also includes the option to register for an “Alert”
feature to receive an automatic email notification when new updates and other information are posted
regarding the document.
ISBN: 978-145591277-3 (SB Print)
ISBN: 978-145591278-0 (LL Print)
ISBN: 978-145591279-7 (Spiral Print)
ISBN: 978-145591280-3 (PDF)
1 2 3 4 5 LSC 20 19 18 17 16
, IMPORTANT NOTICES AND DISCLAIMERS CONCERNING NFPA® STANDARDS
Updating of NFPA Standards
Users of NFPA codes, standards, recommended practices, and guides (“NFPA Standards”) should be aware that
these documents may be superseded at any time by the issuance of new editions or may be amended from time to
time through the issuance of Tentative Interim Amendments or corrected by Errata. An official NFPA Standard at
any point in time consists of the current edition of the document together with any Tentative Interim Amendments
and any Errata then in effect. In order to determine whether a given document is the current edition and whether
it has been amended through the issuance of Tentative Interim Amendments or corrected through the issuance of
Errata, consult appropriate NFPA publications such as the National Fire Codes® Subscription Service, visit the NFPA
website at www.nfpa.org, or contact the NFPA at the address listed below.
Interpretations of NFPA Standards
A statement, written or oral, that is not processed in accordance with Section 6 of the Regulations Governing the
Development of NFPA Standards shall not be considered the official position of NFPA or any of its Committees and
shall not be considered to be, nor be relied upon as, a Formal Interpretation.
Patents
The NFPA does not take any position with respect to the validity of any patent rights referenced in, related to,
or asserted in connection with an NFPA Standard. The users of NFPA Standards bear the sole responsibility for
determining the validity of any such patent rights, as well as the risk of infringement of such rights, and the NFPA
disclaims liability for the infringement of any patent resulting from the use of or reliance on NFPA Standards.
NFPA adheres to the policy of the American National Standards Institute (ANSI) regarding the inclusion of
patents in American National Standards (“the ANSI Patent Policy”), and hereby gives the following notice pursuant
to that policy:
NOTICE: The user’s attention is called to the possibility that compliance with an NFPA Standard may
require use of an invention covered by patent rights. NFPA takes no position as to the validity of any such
patent rights or as to whether such patent rights constitute or include essential patent claims under the
ANSI Patent Policy. If, in connection with the ANSI Patent Policy, a patent holder has filed a statement of
willingness to grant licenses under these rights on reasonable and nondiscriminatory terms and conditions to
applicants desiring to obtain such a license, copies of such filed statements can be obtained, on request, from
NFPA. For further information, contact the NFPA at the address listed below.
Law and Regulations
Users of NFPA Standards should consult applicable federal, state, and local laws and regulations. NFPA does not,
by the publication of its codes, standards, recommended practices, and guides, intend to urge action that is not in
compliance with applicable laws, and these documents may not be construed as doing so.
Copyrights
NFPA Standards are copyrighted. They are made available for a wide variety of both public and private uses. These
include both use, by reference, in laws and regulations, and use in private self-regulation, standardization, and the
promotion of safe practices and methods. By making these documents available for use and adoption by public
authorities and private users, the NFPA does not waive any rights in copyright to these documents.
Use of NFPA Standards for regulatory purposes should be accomplished through adoption by reference. The term
“adoption by reference” means the citing of title, edition, and publishing information only. Any deletions, additions,
and changes desired by the adopting authority should be noted separately in the adopting instrument. In order
to assist NFPA in following the uses made of its documents, adopting authorities are requested to notify the NFPA
(Attention: Secretary, Standards Council) in writing of such use. For technical assistance and questions concerning
adoption of NFPA Standards, contact NFPA at the address below.
For Further Information
All questions or other communications relating to NFPA Standards and all requests for information on NFPA
procedures governing its codes and standards development process, including information on the procedures for
requesting Formal Interpretations, for proposing Tentative Interim Amendments, and for proposing revisions to
NFPA standards during regular revision cycles, should be sent to NFPA headquarters, addressed to the attention
of the Secretary, Standards Council, NFPA, 1 Batterymarch Park, P.O. Box 9101, Quincy, MA 02269-9101; email:
For more information about NFPA, visit the NFPA website at www.nfpa.org. All NFPA codes and standards can be
viewed at no cost at www.nfpa.org/docinfo.
, Copyright © 2016 National Fire Protection Association®. All Rights Reserved.
NFPA 70®
®
National Electrical Code
2017 Edition
This edition of NFPA 70, National Electrical Code, was prepared by the National Electrical Code
Committee and acted on by NFPA at its June Association Technical Meeting held June 13–16, 2016,
in Las Vegas, NV. It was issued by the Standards Council on August 4, 2016, with an effective date of
August 24, 2016, and supersedes all previous editions.
This document has been amended by one or more Tentative Interim Amendments (TIAs) and/or
Errata. See “Codes & Standards” at www.nfpa.org for more information.
This edition of NFPA 70 was approved as an American National Standard on August 24, 2016.
History and Development of the National Electrical Code ®
The National Fire Protection Association has acted as sponsor of the National Electrical Code since
1911. The original Code document was developed in 1897 as a result of the united efforts of various
insurance, electrical, architectural, and allied interests.
In accordance with the Regulations Governing the Development of NFPA Standards, a National
Electrical Code First Draft Report containing proposed amendments to the 2014 National Electrical
Code was published by NFPA in July 2015. This report recorded the actions of the various Code-
Making Panels and the Correlating Committee of the National Electrical Code Committee on each
public input and first revision that had been made to revise the 2014 Code. The report was published
at www.nfpa.org/70. Following the close of the public comment period, the Code-Making Panels
met, acted on each comment, and created some second revisions, which were reported to the
Correlating Committee. NFPA published the National Electrical Code Second Draft Report in April
2016, which recorded the actions of the Code-Making Panels and the Correlating Committee on
each public comment on the National Electrical Code Committee First Draft Report. The National
Electrical Code First Draft Report and the National Electrical Code Second Draft Report were
presented to the 2016 June Association Technical Meeting for adoption.
NFPA has an Electrical Section that provides particular opportunity for NFPA members interested
in electrical safety to become better informed and to contribute to the development of the National
Electrical Code and other NFPA electrical standards. At the Electrical Section Codes and Standards
Review Session held at the 2016 NFPA Conference and Expo, Section members had the opportunity
to discuss and review the report of the National Electrical Code Committee prior to the adoption of
this edition of the Code by the Association at its 2016 June Technical Session.
This 54th edition supersedes all other previous editions, supplements, and printings dated 1897,
1899, 1901, 1903, 1904, 1905, 1907, 1909, 1911, 1913, 1915, 1918, 1920, 1923, 1925, 1926, 1928, 1930,
1931, 1933, 1935, 1937, 1940, 1942, 1943, 1947, 1949, 1951, 1953, 1954, 1955, 1956, 1957, 1958, 1959,
1962, 1965, 1968, 1971, 1975, 1978, 1981, 1984, 1987, 1990, 1993, 1996, 1999, 2002, 2005, 2008, 2011,
and 2014.
This Code is purely advisory as far as NFPA is concerned. It is made available for a wide variety of
both public and private uses in the interest of life and property protection. These include both use in
law and for regulatory purposes and use in private self-regulation and standardization activities such
as insurance underwriting, building and facilities construction and management, and product
testing and certification.
NFPA 70, National Electrical Code, NFPA, and National Fire Protection Association are registered trademarks of the National Fire Protection Association,
Quincy, Massachusetts, 02169
National Electrical Code
International Electrical Code® Series
2017
See ALERT
,Copyright © 2016
National Fire Protection Association®
One Batterymarch Park
Quincy, Massachusetts 02169-7471
NFPA, NFPA 70, National Fire Protection Association, National Electrical Code, and NEC
are registered trademarks of the National Fire Protection Association.
IMPORTANT NOTICES AND DISCLAIMERS CONCERNING NFPA® STANDARDS
NOTICE AND DISCLAIMER OF LIABILITY CONCERNING THE USE OF NFPA STANDARDS
NFPA® codes, standards, recommended practices, and guides (“NFPA Standards”), of which the document contained herein
is one, are developed through a consensus standards development process approved by the American National Standards
Institute. This process brings together volunteers representing varied viewpoints and interests to achieve consensus on fire
and other safety issues. While the NFPA administers the process and establishes rules to promote fairness in the development
of consensus, it does not independently test, evaluate, or verify the accuracy of any information or the soundness of any
judgments contained in NFPA Standards.
The NFPA disclaims liability for any personal injury, property or other damages of any nature whatsoever, whether special,
indirect, consequential or compensatory, directly or indirectly resulting from the publication, use of, or reliance on NFPA
Standards. The NFPA also makes no guaranty or warranty as to the accuracy or completeness of any information published
herein.
In issuing and making NFPA Standards available, the NFPA is not undertaking to render professional or other services for or
on behalf of any person or entity. Nor is the NFPA undertaking to perform any duty owed by any person or entity to someone
else. Anyone using this document should rely on his or her own independent judgment or, as appropriate, seek the advice of a
competent professional in determining the exercise of reasonable care in any given circumstances.
The NFPA has no power, nor does it undertake, to police or enforce compliance with the contents of NFPA Standards.
Nor does the NFPA list, certify, test, or inspect products, designs, or installations for compliance with this document. Any
certification or other statement of compliance with the requirements of this document shall not be attributable to the NFPA
and is solely the responsibility of the certifier or maker of the statement.
See ALERT
ALERT: THIS STANDARD HAS BEEN MODIFIED BY A TIA OR ERRATA
Users of NFPA codes, standards, recommended practices, and guides (“NFPA Standards”) should be
aware that NFPA Standards may be amended from time to time through the issuance of Tentative Interim
Amendments or corrected by Errata. An official NFPA Standard at any point in time consists of the current
edition of the document together with any Tentative Interim Amendment and any Errata then in effect.
In order to determine whether an NFPA Standard has been amended through the issuance
of Tentative Interim Amendments or corrected by Errata, visit the “Codes & Standards” section on NFPA’s
website. There, the document information pages located at the “List of NFPA Codes & Standards” provide
up-to-date, document-specific information including any issued Tentative Interim Amendments and Errata.
To view the document information page for a specific NFPA Standard, go to
http://www.nfpa.org/docinfo to choose from the list of NFPA Standards or use the search feature to select
the NFPA Standard number (e.g., NFPA 101). The document information page includes postings of all
existing Tentative Interim Amendments and Errata. It also includes the option to register for an “Alert”
feature to receive an automatic email notification when new updates and other information are posted
regarding the document.
ISBN: 978-145591277-3 (SB Print)
ISBN: 978-145591278-0 (LL Print)
ISBN: 978-145591279-7 (Spiral Print)
ISBN: 978-145591280-3 (PDF)
1 2 3 4 5 LSC 20 19 18 17 16
, IMPORTANT NOTICES AND DISCLAIMERS CONCERNING NFPA® STANDARDS
Updating of NFPA Standards
Users of NFPA codes, standards, recommended practices, and guides (“NFPA Standards”) should be aware that
these documents may be superseded at any time by the issuance of new editions or may be amended from time to
time through the issuance of Tentative Interim Amendments or corrected by Errata. An official NFPA Standard at
any point in time consists of the current edition of the document together with any Tentative Interim Amendments
and any Errata then in effect. In order to determine whether a given document is the current edition and whether
it has been amended through the issuance of Tentative Interim Amendments or corrected through the issuance of
Errata, consult appropriate NFPA publications such as the National Fire Codes® Subscription Service, visit the NFPA
website at www.nfpa.org, or contact the NFPA at the address listed below.
Interpretations of NFPA Standards
A statement, written or oral, that is not processed in accordance with Section 6 of the Regulations Governing the
Development of NFPA Standards shall not be considered the official position of NFPA or any of its Committees and
shall not be considered to be, nor be relied upon as, a Formal Interpretation.
Patents
The NFPA does not take any position with respect to the validity of any patent rights referenced in, related to,
or asserted in connection with an NFPA Standard. The users of NFPA Standards bear the sole responsibility for
determining the validity of any such patent rights, as well as the risk of infringement of such rights, and the NFPA
disclaims liability for the infringement of any patent resulting from the use of or reliance on NFPA Standards.
NFPA adheres to the policy of the American National Standards Institute (ANSI) regarding the inclusion of
patents in American National Standards (“the ANSI Patent Policy”), and hereby gives the following notice pursuant
to that policy:
NOTICE: The user’s attention is called to the possibility that compliance with an NFPA Standard may
require use of an invention covered by patent rights. NFPA takes no position as to the validity of any such
patent rights or as to whether such patent rights constitute or include essential patent claims under the
ANSI Patent Policy. If, in connection with the ANSI Patent Policy, a patent holder has filed a statement of
willingness to grant licenses under these rights on reasonable and nondiscriminatory terms and conditions to
applicants desiring to obtain such a license, copies of such filed statements can be obtained, on request, from
NFPA. For further information, contact the NFPA at the address listed below.
Law and Regulations
Users of NFPA Standards should consult applicable federal, state, and local laws and regulations. NFPA does not,
by the publication of its codes, standards, recommended practices, and guides, intend to urge action that is not in
compliance with applicable laws, and these documents may not be construed as doing so.
Copyrights
NFPA Standards are copyrighted. They are made available for a wide variety of both public and private uses. These
include both use, by reference, in laws and regulations, and use in private self-regulation, standardization, and the
promotion of safe practices and methods. By making these documents available for use and adoption by public
authorities and private users, the NFPA does not waive any rights in copyright to these documents.
Use of NFPA Standards for regulatory purposes should be accomplished through adoption by reference. The term
“adoption by reference” means the citing of title, edition, and publishing information only. Any deletions, additions,
and changes desired by the adopting authority should be noted separately in the adopting instrument. In order
to assist NFPA in following the uses made of its documents, adopting authorities are requested to notify the NFPA
(Attention: Secretary, Standards Council) in writing of such use. For technical assistance and questions concerning
adoption of NFPA Standards, contact NFPA at the address below.
For Further Information
All questions or other communications relating to NFPA Standards and all requests for information on NFPA
procedures governing its codes and standards development process, including information on the procedures for
requesting Formal Interpretations, for proposing Tentative Interim Amendments, and for proposing revisions to
NFPA standards during regular revision cycles, should be sent to NFPA headquarters, addressed to the attention
of the Secretary, Standards Council, NFPA, 1 Batterymarch Park, P.O. Box 9101, Quincy, MA 02269-9101; email:
For more information about NFPA, visit the NFPA website at www.nfpa.org. All NFPA codes and standards can be
viewed at no cost at www.nfpa.org/docinfo.
, Copyright © 2016 National Fire Protection Association®. All Rights Reserved.
NFPA 70®
®
National Electrical Code
2017 Edition
This edition of NFPA 70, National Electrical Code, was prepared by the National Electrical Code
Committee and acted on by NFPA at its June Association Technical Meeting held June 13–16, 2016,
in Las Vegas, NV. It was issued by the Standards Council on August 4, 2016, with an effective date of
August 24, 2016, and supersedes all previous editions.
This document has been amended by one or more Tentative Interim Amendments (TIAs) and/or
Errata. See “Codes & Standards” at www.nfpa.org for more information.
This edition of NFPA 70 was approved as an American National Standard on August 24, 2016.
History and Development of the National Electrical Code ®
The National Fire Protection Association has acted as sponsor of the National Electrical Code since
1911. The original Code document was developed in 1897 as a result of the united efforts of various
insurance, electrical, architectural, and allied interests.
In accordance with the Regulations Governing the Development of NFPA Standards, a National
Electrical Code First Draft Report containing proposed amendments to the 2014 National Electrical
Code was published by NFPA in July 2015. This report recorded the actions of the various Code-
Making Panels and the Correlating Committee of the National Electrical Code Committee on each
public input and first revision that had been made to revise the 2014 Code. The report was published
at www.nfpa.org/70. Following the close of the public comment period, the Code-Making Panels
met, acted on each comment, and created some second revisions, which were reported to the
Correlating Committee. NFPA published the National Electrical Code Second Draft Report in April
2016, which recorded the actions of the Code-Making Panels and the Correlating Committee on
each public comment on the National Electrical Code Committee First Draft Report. The National
Electrical Code First Draft Report and the National Electrical Code Second Draft Report were
presented to the 2016 June Association Technical Meeting for adoption.
NFPA has an Electrical Section that provides particular opportunity for NFPA members interested
in electrical safety to become better informed and to contribute to the development of the National
Electrical Code and other NFPA electrical standards. At the Electrical Section Codes and Standards
Review Session held at the 2016 NFPA Conference and Expo, Section members had the opportunity
to discuss and review the report of the National Electrical Code Committee prior to the adoption of
this edition of the Code by the Association at its 2016 June Technical Session.
This 54th edition supersedes all other previous editions, supplements, and printings dated 1897,
1899, 1901, 1903, 1904, 1905, 1907, 1909, 1911, 1913, 1915, 1918, 1920, 1923, 1925, 1926, 1928, 1930,
1931, 1933, 1935, 1937, 1940, 1942, 1943, 1947, 1949, 1951, 1953, 1954, 1955, 1956, 1957, 1958, 1959,
1962, 1965, 1968, 1971, 1975, 1978, 1981, 1984, 1987, 1990, 1993, 1996, 1999, 2002, 2005, 2008, 2011,
and 2014.
This Code is purely advisory as far as NFPA is concerned. It is made available for a wide variety of
both public and private uses in the interest of life and property protection. These include both use in
law and for regulatory purposes and use in private self-regulation and standardization activities such
as insurance underwriting, building and facilities construction and management, and product
testing and certification.
NFPA 70, National Electrical Code, NFPA, and National Fire Protection Association are registered trademarks of the National Fire Protection Association,
Quincy, Massachusetts, 02169
