{"abstract":"The U.S. Nuclear Regulatory Commission (NRC) is issuing a new Regulatory Guide (RG) 1.257, \"Qualification of Fiber-Optic Cables, Connections, and Optical Fiber Splices for Use in Safety Systems for Production and Utilization Facilities.\" This RG describes an approach that is acceptable to the staff of the NRC for use in complying with the NRC's regulations that address the environmental qualification of fiber-optic cables, connections, and optical fiber splices in safety systems in production and utilization facilities. This RG endorses, subject to the conditions described in Section C of the RG, the Institute of Electrical and Electronics Engineers (IEEE) Standard 1682- 2023, \"IEEE Standard for Qualifying Fiber Optic Cables, Connections, and Optical Fiber Splices for Use in Safety Systems in Nuclear Power Generating Stations.\"","action":"Final guide; issuance.","agencies":[{"raw_name":"NUCLEAR REGULATORY COMMISSION","name":"Nuclear Regulatory Commission","id":383,"url":"https://www.federalregister.gov/agencies/nuclear-regulatory-commission","json_url":"https://www.federalregister.gov/api/v1/agencies/383","parent_id":null,"slug":"nuclear-regulatory-commission"}],"body_html_url":"https://www.federalregister.gov/documents/full_text/html/2025/08/12/2025-15227.html","cfr_references":[],"citation":"90 FR 38827","comment_url":null,"comments_close_on":null,"correction_of":null,"corrections":[],"dates":"Revision 0 to RG 1.257 is available on August 12, 2025.","disposition_notes":null,"docket_ids":["NRC-2024-0161"],"dockets":[{"supporting_documents":[{"title":"Draft Regulatory Guide Qualification of Fiber-Optic Cables Connections and Optical Fiber Splices for Use in Safety Systems for Production and Utilization Facilities","document_id":"NRC-2024-0161-0002"}],"agency_name":"NRC","documents":[{"comment_count":null,"comment_start_date":null,"updated_at":"2025-08-12T09:59:09.161-04:00","comment_url":"https://www.regulations.gov/commenton/NRC-2024-0161-0004","allow_late_comments":false,"id":"NRC-2024-0161-0004","comment_end_date":null,"regulations_dot_gov_open_for_comment":false}],"supporting_documents_count":1,"id":"NRC-2024-0161","title":"Draft Regulatory Guide: Qualification of Fiber-Optic Cables, Connections, and Optical Fiber Splices for Use in Safety Systems for Production and Utilization Facilities"}],"document_number":"2025-15227","effective_on":null,"end_page":38828,"executive_order_notes":null,"executive_order_number":null,"explanation":null,"full_text_xml_url":"https://www.federalregister.gov/documents/full_text/xml/2025/08/12/2025-15227.xml","html_url":"https://www.federalregister.gov/documents/2025/08/12/2025-15227/regulatory-guide-qualification-of-fiber-optic-cables-connections-and-optical-fiber-splices-for-use","images":{},"images_metadata":{},"json_url":"https://www.federalregister.gov/api/v1/documents/2025-15227?publication_date=2025-08-12","mods_url":"https://www.govinfo.gov/metadata/granule/FR-2025-08-12/2025-15227/mods.xml","not_received_for_publication":null,"page_length":2,"page_views":{"count":100,"last_updated":"2026-04-04 04:15:05 -0400"},"pdf_url":"https://www.govinfo.gov/content/pkg/FR-2025-08-12/pdf/2025-15227.pdf","presidential_document_number":null,"proclamation_number":null,"public_inspection_pdf_url":"https://public-inspection.federalregister.gov/2025-15227.pdf?1754916306","publication_date":"2025-08-12","raw_text_url":"https://www.federalregister.gov/documents/full_text/text/2025/08/12/2025-15227.txt","regulation_id_number_info":{},"regulation_id_numbers":[],"regulations_dot_gov_info":{"supporting_documents":[{"title":"Draft Regulatory Guide Qualification of Fiber-Optic Cables Connections and Optical Fiber Splices for Use in Safety Systems for Production and Utilization Facilities","document_id":"NRC-2024-0161-0002"}],"comments_count":0,"agency_id":"NRC","comments_url":"https://www.regulations.gov/docketBrowser?rpp=50&so=DESC&sb=postedDate&po=0&dct=PS&D=NRC-2024-0161","supporting_documents_count":1,"docket_id":"NRC-2024-0161","document_id":"NRC-2024-0161-0004","regulation_id_number":null,"title":"Draft Regulatory Guide: Qualification of Fiber-Optic Cables, Connections, and Optical Fiber Splices for Use in Safety Systems for Production and Utilization Facilities","checked_regulationsdotgov_at":"2025-08-13T16:55:04Z"},"regulations_dot_gov_url":null,"significant":null,"signing_date":null,"start_page":38827,"subtype":null,"title":"Regulatory Guide: Qualification of Fiber-Optic Cables, Connections, and Optical Fiber Splices for Use in Safety Systems for Production and Utilization Facilities","toc_doc":"Qualification of Fiber-Optic Cables, Connections, and Optical Fiber Splices for Use in Safety Systems for Production and Utilization Facilities","toc_subject":"Regulatory Guide","topics":[],"type":"Notice","volume":90}