Proposed Generic Communication; Post-Fire Safe-Shutdown Circuit Analysis Spurious Actuations
The U.S. Nuclear Regulatory Commission (NRC) is proposing to issue a generic letter (GL) to: (1) Request addressees to review their fire protection program to confirm compliance with existing applicable regulatory requirements regarding their assumptions of the phrase ``one-at-a-time'' in light of the information provided in this GL and, if appropriate, take additional actions to return to compliance. Specifically, although some licensees have performed their post-fire, safe-shutdown circuit analyses based on an assumption of only a single spurious actuation per fire event or that spurious actuations will occur ``one-at-a-time,'' recent industry cable fire test results demonstrated that these assumptions are not valid. (2) Require addressees to submit a written response to the NRC in accordance with NRC regulations in Title 10 of the Code of Federal Regulations, Section 50.54(f) (10 CFR 50.54(f)). This Federal Register notice is available through the NRC's Agencywide Documents Access and Management System (ADAMS) under accession number ML051650017.