Document: NRC Regulatory Guide
Document ID: 22ccfd5e-c5d8-4615-a02c-32369aa9f533
Document Type: regulatory_guide
Title: Acceptability of Probabilistic Risk Assessment Results for Risk-Informed Activities (Rev. 3)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1930/ML19308B636.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.200
CFR Part: 
CFR Title: 

Content:
…including specification of the failure modes, including spurious operation. FSS-A4 Use of language, “one or more,” is problematic, since it does not specify a minimum requirement. Clarification IDENTIFY sufficient one or more combinations of target sets ... has been represented. FSS-A5 The number of individual fire scenarios and level of detail should be commensurate with the relative risk importance of the physical analysis unit. Clarification Cat I and II: For each unscreened … can be characterized commensurate with its risk significance. NOTE FSS-A5-5: It is expected … will be commensurate with the capability category and the fire relative risk importance … FSS-B1, B2 -------------------- No objection -------------------- FSS-C1, FSS- C3 thru FSS-C8 -------------------- No objection -------------------- DG-1362, Appendix A, Page A-28 Table A-4. Staff Position on ASME/ANS RA-Sa-2009 Part 4, Technical and Peer Review Requirements for At-Power Internal Fire Index No Issue Position Resolution FSS-C2 See Issue for ES-C1 Clarification Cat II and III: For those scenarios that represent significant contributors to a physical analysis unit’s fire risk, CHARACTERIZE … NOTE FSS-C3-3: … are not significant contributors (as defined in Part 1), … FSS-D1, FSS-D2, FSS-D4 thru FSS-D11 -------------------- No objection -------------------- FSS-D3 Again the “either bounded or accurately characterized” issue for CC II and CC III. Clarification Cat I: …in the analysis of each fire scenario such that the fire risk contribution of each unscreened physical analysis unit is bounded. Cat II: …the fire risk contribution of each unscreened physical analysis unit can be either bounded or accurately characterized. Cat III: …the fire risk contribution of each unscreened physical analysis unit can be either bounded or accurately characterized and such that the risk… FSS-E1 thru FSS-E4 -------------------- No objection -------------------- FSS-F1 Use of the term