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:
d their impact on the PRA model • Understanding of the impact of the assumptions on Level 2 results Technical Elements for PRA Documentation The documentation of the PRA model provides the necessary information so that the results can easily be reproduced and justified. 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 through documenting the actual process in the PRA documentation, or through reference to existing methodology documents. Sources of uncertainty (both parameter and model) are identified and their impact on the results are 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 DG-1362, Page 35 criteria, reactor coolant pressure seal LOCA model, human reliability model). A key source of uncertainty is where the choice of approach or model is known to have an impact on the risk profile (e.g., total CDF and total LERF), the set of initiating events and accident sequences that contribute most to CDF and to LERF such that it influences a decision being made using the PRA. Assumptions made in performing the analyses are identified and documented along with their justification to the extent that the context of the assumption is understood. The results (e.g., products and outcomes) from the various analyses are documented. Table 13 summarizes the characteristics and attributes needed for documentation for each hazard group and associated technical elements. Table 13. Summary of Technical Characteristics and Attributes for PRA Documentation Element Technical Characteristics and Attributes Traceability and Justification • The documentation is sufficient to facilitate independent peer reviews. • The documentation describes the interim results (sufficient to provide traceability and defensibility of the