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:
l provides the information necessary to easily reproduce and justify results. The sources of information used in the PRA also should be referenced and retrievable. The methodology used to perform each aspect of the work is described either by documenting the actual process in the PRA documentation or by reference to existing methodology documents. Sources of both parameter and model uncertainty are identified and documented, and their impact on the results is assessed generally for each technical element. A source of model uncertainty is one that is related to an issue for which there is no consensus approach or model (e.g., choice of data source, success criteria, human reliability model). A key source of uncertainty is one in which the choice of approach or model is known to have an impact on the risk (e.g., total integrated risk, risk of a source, POS, hazard group, frequency of an event sequence or event sequence family, importance measures), or the set of initiating events and event sequences that contribute most to the consequence risk, such that the impact influences a decision supported by the PRA. Assumptions made in performing the analyses are identified and documented along with their justifications to the extent that the context of the assumption is understood. The results (e.g., products and outcomes) from the various analyses are documented. The characteristics and attributes needed for documentation of a given PRA analysis element are as follows: • The documentation is sufficient to facilitate independent peer reviews. • The documentation describes the interim results (sufficient to provide traceability and defensibility of the final results) and the final results and insights. • The documentation describes the processes used to perform the analyses for each PRA element sufficient to understand the bases of the results of the PRA, including any analysis that is unique to a PRA analysis element. • The documentation describes the identification