Document: NUREG-0800
Document ID: 8dd882f4-a34f-4415-acd1-ebb441c72786
Document Type: srp
Title: PROBABILISTIC RISK ASSESSMENT AND SEVERE ACCIDENT
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1213/ML12132A481.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19.0
CFR Part: 
CFR Title: 

Content:
aff will determine that the applicant has performed risk importance studies at the system, train, and component level that adequately provide insights about (1) the systems that contribute the most in achieving the low risk level assessed in the PRA, (2) events (e.g., component failures or human errors) that contribute the most to decreases in the built-in plant safety level, and (3) events that contribute the most to the assessed risk. 8. The staff will determine that the applicant’s uncertainty analysis identifies major contributors to the uncertainty associated with the estimated risks. The staff will determine, for designs using passive safety systems and active defense-in-depth systems, that the applicant has performed sensitivity studies without credit for the non- safety-related defense-in-depth systems. These studies provide additional insights about the risk importance of the defense-in-depth systems that are taken into account in selecting non-safety-related systems for regulatory treatment according to the 19.0-13 Draft Revision 3 – September 2012 Regulatory Treatment of Non-safety Systems (RTNSS ) process (See SRP Section 19.3 for additional information). 9. Consistent with the guidance in Section 2.5 of RG 1.174, the staff expects that the applicant will have subjected its PRA to quality control. In accordance with the Statement of Consideration for the revised Part 52 (72 FR 49365), the PRA is not part of the design-basis information, therefore, the PRA is not subject to the quality assurance requirements of 10 CFR Part 50, Appendix B. However, the applicant should address the following methods of quality control: A. Use of personnel qualified for the analysis B. Use of procedures that ensure control of documentation, including revisions, and provide for independent review, verification, or checking of calculations and information used in the analyses C. Documentation and maintenance of records, including archival documentation as well as submittal