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:
he context of the staff position in this RG, relevant application-specific regulatory guidance, and the related requirements (e.g., license condition) for the application. The application-specific RGs identify the specific PRA results used to support the decision- making and the portions of the base PRA needed to provide those results. The portions of the base PRA DG-1362, Page 47 needed to support the application-specific analysis should be identified and the guidance in this RG applies to those portions. Regulatory positions C.3.1 and C.3.2 summarize the staff position on the outcome of the application of the application-specific RGs in determining the scope of application of this RG. One acceptable approach to demonstrate conformance with regulatory positions C.3.1 and C.3.2 is to use a national consensus standard. The ASME/ANS Level 1/LERF PRA standard provides the technical requirements for this purpose. If the ASME/ANS Level 1/LERF PRA standard is implemented, as endorsed by the staff in Appendices A and B of this RG, as applicable, with exceptions and clarifications, regulatory positions C.3.1 and C.3.2 are considered to be met. When using this RG, it is anticipated that the licensee’s description of the application should include the following: • SSCs, operator actions, and plant operational characteristics affected by the application • a description of the cause-effect relationships related to the change and the affected SSCs, operator actions, and plant operational characteristics • mapping of the cause-effect relationships onto PRA model elements • identification of the PRA results that will be used to compare against the applicable acceptance criteria or guidelines and how the comparison is to be made • the scope of risk contributors (hazard groups and modes of operation) included in the PRA to support the decision 3.1 Scope of Risk Contributors Addressed by the PRA Model Based on the definition of the application, and in particular the