Nuclear Regulatory Commission May 13, 2005 – Federal Register Recent Federal Regulation Documents

The U.S. Nuclear Regulatory Commission (NRC) is proposing to issue a regulatory information summary (RIS) to clarify regulatory requirement issues associated with post-fire safe-shutdown circuit analyses and protection, particularly the requirements of Title 10 of the Code of Federal Regulations, Part 50 (10 CFR 50), Appendix R, which have been interpreted by licensees in a manner that is not consistent with regulatory expectations. The industry and NRC regional inspectors have requested clarification of regulatory expectations with respect to post-fire safe-shutdown circuits. In addition, clarification of these requirements will assist licensees in evaluating the transition to a risk-informed, performance-based fire protection program. Three terms are to be addressed in this RIS: ``any-and-all'' (with respect to spurious actuations), ``associated circuits,'' and ``emergency control station.'' Clarification of the term ``one-at-a- time'' (with respect to spurious actuations) will be provided in a separate generic communication. For each term addressed, this RIS identifies the applicable NRC regulatory requirement, provides the regulatory expectation with respect to the requirement, and specifies one acceptable approach to achieving regulatory compliance. Attachment 1 to this RIS provides additional discussion that explains the basis for the regulatory expectations, including a discussion of the various ways in which each term or phrase has been interpreted by stakeholders. This RIS also gives the staff's views on the use of Nuclear Energy Institute (NEI) guidance document NEI 00-01, ``Guidance for Post-Fire Safe Shutdown Circuit Analysis,'' Revision 1 (ML050310295), in complying with Appendix R. The deterministic methodology presented in NEI 00-01, in conjunction with the guidance in this RIS, is one acceptable approach to achieving regulatory compliance with post-fire safe-shutdown circuit protection requirements. Note that RIS 2004-03, Revision 1, ``Risk-Informed Approach for Post-Fire Safe-Shutdown Circuit Inspections'' (ML042440791) provides guidance on conducting risk-informed circuit inspections, whereas this RIS clarifies the regulatory requirements for compliance with Appendix R. This Federal Register notice is available through the NRC's Agencywide Documents Access and Management System (ADAMS) under accession number ML051110160.