Final rule · 2025-02065

Regulatory Guides: Criteria for Power Systems for Nuclear Power Plants and Criteria for the Protection of Class 1E Power Systems and Equipment for Nuclear Power Plants

The U.S. Nuclear Regulatory Commission (NRC) is issuing Revision 4 to Regulatory Guide (RG) 1.32, "Criteria for Power Systems for Nuclear Power Plants," and new RG 1.238, "Criteria for the Protection of Class 1E Power Systems and Equipment for Nuclear Power Plants." RG 1.32, Revision 4, describes an acceptable approach for use in complying with NRC regulations for the design, operation, and testing of electric power systems in nuclear power plants. RG 1.238 describes an acceptable approach for use in complying with NRC regulations for protection of Class 1E power systems and equipment at nuclear power plants. The NRC is also withdrawing RG 1.41, "Preoperational Testing of Redundant On-Site Electric Power Systems to Verify Proper Load Group Assignments," since its guidance is incorporated into RG 1.32, Revision 4.