IEEE SA STANDARDS ASSOCIATION IEEE Standard for Electric Penetration ISTANDARDS Assemblies in Containment Structures for Nuclear Power Generating Stations IEEEPower and EnergySociety Developed by the NuclearPowerEngineeringCommittee IEEEStd317TM-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 Developedbythe NuclearPowerEngineeringCommittee of the IEEEPowerandEnergySociety Approved19June2025 IEEESAStandardsBoard Abstract: An electric penetration assembly is an assembly of insulated electric conductors, pressure barrier between the inside and the outside of the containment structure. The electric penetration assembly includes terminal (junction)boxes,terminal blocks,connectors and cable 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 penetration assemblies in nuclear containment structures for stationary nuclear power generating 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 United States Nuclear Regulatory Commission's Code of Federal Regulations (10CFR50)are presented in this standard. Keywords:apertureseals,class MC components，conductor seals,containmentelectric penetration assembly, containment penetrations, control power penetrations,DBE,design basis events, electric penetration assembly, electrical penetration assembly,fiber seals, IEEE 317TM, instrumentation penetrations,low voltage power penetrations,LvP,medium voltage power penetrations,module seals,MvP,penetration feedthroughs,penetration modules,qualified life SAC, severe accident conditions The Institute of Electrical and Electronics Engineers, Inc. 3 Park Avenue, New York, NY 10016-5997, USA Copyright 2025 by The Institute 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 IEEEprohibits discrimination, harassment, and bullying. Formoreinformation,visithttps://www.ieee.org/about/corporate/governance/pg-26.htm. No part of this publication may be reproduced in any form, in an electronic retrieval system or otherwise, without the prior written permission of the publisher. ImportantNoticesandDisclaimersConcerningIEEEStandardsDocuments 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 StandardsDocuments 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 developmentprocess,whichbringstogethervolunteers representing varied viewpoints andintereststo 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 are not necessarily members of IEEE