Document: NRC Regulatory Guide
Document ID: 666e1303-0170-4974-a7d6-af27eb586524
Document Type: regulatory_guide
Title: Risk-Informed, Performance-Based Fire Protection for Existing Light-Water Nuclear Power Plants (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2104/ML21048A448.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.205
CFR Part: 
CFR Title: 

Content:
proach, methods, and data acceptable. There are two aspects to assessing the technical adequacy of the PRA results. First, the underlying PRA (i.e., the baseline model) should be technically adequate. Second, the analyses, assumptions, and approximations to map the cause-effect relationship associated with the application must be technically adequate. The licensee may address the first aspect for risk-informed applications by conforming to the peer review and self-assessment processes in RG 1.200. This RG provides one approach acceptable to the NRC for determining the technical adequacy of the baseline PRA model. RG 1.200 endorses, with certain clarifications and qualifications, Addendum A to the American Society of Mechanical Engineers/American Nuclear Society (ASME/ANS) RA-Sa 2009, “Standard for Probabilistic Risk Assessment for Nuclear Power Plant Applications” (“PRA Standard”) (Ref. 32). The licensee should address the second aspect by describing the specific modeling of each cause and effect relationship associated with the application. The NRC staff will review the engineering analyses, assumptions, and approximations made in developing and using the PRA model to determine 7 For more information on these codes, the user is encouraged to contact the National Institute of Standards and Technology at 100 Bureau Drive, Gaithersburg, MD 20899; phone: 301-975-2000; website: https://www.nist.gov/ and the Electricité de France at phone: +33 (0) 1 4042 4637, website: https://www.edf.fr/en/the-edf-group. RG 1.205, Revision 2, Page 26 whether they are appropriate, focusing on the key assumptions (i.e., those that are significant to the application), as outlined in NUREG-0800, Section 19.1, “Determining the Technical Adequacy of Probabilistic Risk Assessment for Risk-Informed License Amendment Requests after Initial Fuel Load” (Ref. 33). The licensee should submit the documentation described in Section 4.2 of RG 1.200 to address the baseline PRA and