National Fuel Gas Code
2021
2021NATIONALFUELGASCODE FRONTCOVER
Fifteenth Edition 2021First PrintingPrinted in U.S.A.American Gas Association
An American National Standard
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NFPA codes standards remended practices and guides (*NFPA Standards") of which the documentcontained herein is one and AGA's Z223.1 are developed through a consensus standards development process approvedby theAmrican National Stadards IstiuteThis proces brings togetherolunteersreresenting varidthe process and establish rales to promote faimess in the development of consensus they do not independently test viewpoints and intrests to achieve consensus onfre and the safety issues. While theAGA and theNFPA administrevaluate or verify the accuracy of any infomation or the soundness of any judgments contained in their codes andstandards.
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Th AGA and tPAhavepower nrdthydake tpolicrnf mlie withth ntets fthis documet. Nor do the AGA and the NFPA lis certify test or inspect products designs or installtions forplianc withthsdocmennycerifictionrthrstatement of lian withthrequirements f this document shall not be atrbutable to the AGA and the NFPA and is solely the responsibility of the certifier or makerof the statement.
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REMINDER: UPDATING OF STANDARDS
NFPA: Users of NFPA codes standards remended practices and guides (*NFPA Standards") should be awarethat NFPA Standards may be amended from time to time through the issuance of a Tentative Interim Amendment （TIA) r corrected by ErrataAn oficil NFPAStandard at any poit in time consists of the current editionof thepage provides up-to-date document-specific infomation as well as postings of all existing TIAs and Erata. It also ueou mop u aoeu o “eu q pa ao s jo ss a q8no ppuincludes 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.
an Amendment or corected by Eata.An official ANSI Z223.1 code at any point n time cnsists of the current ASC Z223: Users of the ANSI Z223.1 code should be aware that the code may be amended through the issuance ofZ223.1 has been amended go to edition of the document together with any Amendments and Erata then in effect. To detemine whether the ANSI
ADDITIONAL NOTICES AND DISCLAIMERS
Updating of AGA and NFPA Standards
that these documents may be superseded at any time by the isuance ofnew editions ormay be amendd from time to time through the ise fTentatie Iim Amndmnts or cetdby Eraa Anffcial NFPA r AGA doum at ay point n time Users of NFPA codes standards romended practices and guides (NFPA Standards and AGA Z223.1 should be awareconsistsfthecut iio f th dct togethr withayTntiv Irim mnnts and ay Eatthin ffet order to determine whether a given document is the current odition and whether it has been amended through the issuance ofNatinalFreCdes8 Subcripton Serce visithe PA wesite w.fp ocaet t AGA rNFPA atte addss Tentative Interim Amendments or corretd through the isuance of Erata consult appropriate NFPA plications such as thlisted below.
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A statement written or oral that is not processed in accordance with the interpretation procdures of the Z223 Comitee orZ223 Commite or the NFPA or any of is Commitees and shall not be considred to be nor be relied upon as a Fomal Setion 6 oftheRegulaiosGoeing thDeelpmnt f NFPAStanards shallot e csiderdtheoffcial positi of thInterpretation.
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Users ofAGA and PA docnts should cul alial fdral sate andcalls and rgulatioThAGA an thNFPA do not by the publication of their codes standards remended pcties and guides intend to urge actioe that s not in pliance with applicable laws and this document may not be constred as doing so.
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tibfiilnid UseofAGAandNPA dntsfrregulatry pposes sh b acmlish thrug doptionbyrferneTh mdsiredby ading ity sd b td arlyi ainnstmmndat PAfoin usesmaditsdding attierrqstd ttify thPAAnietrytndsoi writing of such use For techical asistance and questions conceming adoption of AGA and NFPA documents contact the AGA orthe NFPA at the addresses below.
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