IEEE SA STANDARDS ASSOCIATION IEEE Standard for Electric Penetration STANDARDS Assemblies in Containment Structures for Nuclear Power Generating Stations IEEE Power and Energy Society Developed by the Nuclear Power Engineering Committee IEEEStd 317TM-2025 (Revision of IEEE Std 317-2013) IEEE IEEEStd317TM-2025 (Revision of IEEE Std 317-2013) IEEE Standard for Electric Penetration Assemblies in Containment Structures for Nuclear Power Generating Stations Developed by the Nuclear Power Engineering Committee of the IEEEPowerand EnergySociety Approved19 June 2025 IEEE SA Standards Board Abstract: An electric penetration assembly is an assembly of insulated electric conductors, conductors through a single aperture in the nuclear containment structure, while providing a pressure barrier between the inside and the outside of the containment structure. The electric penetrationassemblyincludesterminal(junction)boxes,terminalblocks,connectorsandcable supports, and splices which are designed and furnished as an integral part of the assembly. Requirements for the design, construction, qualification, test, and installation of electric stations are prescribed in this standard. Criteria intended to facilitate the determination of the features of design, construction, test, qualification, and installation relative to the electric penetration assemblies of primary containments of the nuclear facilities that comply with the UnitedStatesNuclearRegulatoryCommission'sCodeofFederalRegulations(1oCFR5O)are presented in this standard. Keywords: aperture seals, class MC components, conductor seals, containment electric penetration assembly, containment penetrations, control power penetrations, DBE, design basis instrumentation penetrations, low voltage power penetrations, LvP, medium voltage power penetrations, module seals, MvP, penetration feedthroughs, penetration modules, qualified life, SAC,severeaccidentconditions The Institute of Electricaland Electronics Engineers, Inc 3 Park Avenue, New York, NY 10016-5997, USA Copyright @ 2025 by The Insttute of Electrical and Electronics Engineers, Inc. All rights reserved. Published 8 August 2025. Printed in the United States of America IEEE is a registered trademark in the U.S. Patent & Trademark Ofice, owned by The Institute of Electrical and Electronics Engineers Incorporated. National Electrical Code, NEC, and NFPA 70 are registered trademarks in the U.S. Patent & Trademark Ofice, owned by the National Fire Protection Association PDF: ISBN 979-8-8557-2388-5 STD28079 Print: ISBN 979-8-8557-2389-2 STDPD28079 IEEE prohibits discrimination, harassment, and bullying Formoreinformation,visithttps://www.ieee.org/about/corporate/governance/p9-26.html Nopartof thispublication may bereproducedinanyform, in anelectronicretrievalsystemorotherwise, without theprior writenpermission of the publisher. Important Notices and Disclaimers Concerning IEEE Standards Documents IEEE Standards documents are made available for use subject to important notices and legal disclaimers. These notices and disclaimers, or a reference to this page (https://standards.ieee.org/ipr/disclaimers.html), appear in all IEEE standards and may be found under the heading “Important Notices and Disclaimers Concerning IEEE Standards Documents." Notice and Disclaimer of Liability Concerning the Use of IEEE Standards Documents IEEE Standards documents are developed within IEEE Societies and subcommittees of IEEE Standards Association (IEEE SA) Board of Governors. IEEE develops its standards through an accredited consensus development process,whichbrings togethervolunteersrepresentingvariedviewpointsand interests to achieve the final product. IEEE standards are documents developed by volunteers with scientific, academic, and industry-based expertise in technical working groups. Volunteers involved in technical working groups arenotnecessarilymembersofIEEEorIEEESAandparticipatewithoutcompensationfromIEEE.While IEEE administers the process and establishe