Document: NRC Regulatory Guide
Document ID: 8a2332d3-66ca-40af-84e1-507db8b26559
Document Type: regulatory_guide
Title: TRIAL - Acceptability of Probabilistic Risk Assessment Results for Non-Light Water Reactor Risk-Informed Activities
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2123/ML21235A008.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.247
CFR Part: 
CFR Title: 

Content:
demonstrating that the event sequences or contributors significant to the application were not impacted; o justification that the PRA has been performed in such a way that its results are acceptable, commensurate with the level of maturity of the design. This should include any commitments for updating the PRA to ensure that it reflects the plant design for and is consistent with the PRA’s intended use in the application. • description of the appropriateness of key assumptions, approximations, and sensitivity studies thereof relevant to the results used in the application. • justification of the appropriateness of a given portion of the PRA that does not meet an SR or meets a CC lower than that deemed appropriate for the application as specified in the application- specific guidance. • description of the appropriateness of PRA model upgrades, including the use of NDMs, for the application under consideration. RG 1.247, Page 66 D. IMPLEMENTATION The NRC staff may use this trial use regulatory guide as a reference in its regulatory processes, such as licensing, inspection, or enforcement. The purpose of a trial use regulatory guide, such as this one, is to allow early use prior to general implementation. As a result, the staff anticipates continuing to evaluate the positions in this regulatory guide. Therefore, staff may withdraw or add positions from this trial use guide after the trial use period ends if a position is determined to be not acceptable. Moreover, this trial use regulatory guide does not establish a staff position for purposes of backfitting as that term is defined in 10 CFR 50.109, “Backfitting,” and as described in NRC Management Directive (MD) 8.4, “Management of Backfitting, Forward Fitting, Issue Finality, and Information Requests”, nor does the NRC staff intend to use the guidance to affect the issue finality of an approval under 10 CFR Part 52, “Licenses, certifications, and approvals for nuclear power plants.” Any changes to