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:
es where the intended function of the design feature is relied upon to resolve postulated accidents when the reactor core has melted and exited the reactor vessel (ex- vessel severe accidents) and the containment is challenged. The location of the ex-vessel severe accident design information in the DCD is not important to the application of this special departure process in paragraph B.5.c. Some design features may have intended functions to meet both “design-basis” requirements and to resolve ex-vessel severe accidents. If these design features are reviewed under paragraph VIII.B.5, then the appropriate criteria from either paragraph B.5.b or B.5.c are selected depending upon from which function the departure is being taken. 6. 10 CFR 52.47(a)(27) states that a DC application must contain an FSAR that includes description of the design-specific PRA and its results. With respect to this regulation, the following items are noted: A. The Statement of Consideration (72 FR 49365) for the revised Part 52 states that the definition of Tier 2 in Section II.E.1 of the DCRs has been modified to exclude the design-specific PRA and the evaluation of SAMDAs. The PRA and SAMDA evaluations do not need to be included in Tier 2 because they are not part of the design-basis information. B. The Statement of Consideration (72 FR 49380) for the revised Part 52 states the understanding that the complete PRA (e.g., codes) will be available for NRC inspection at the applicant’s offices, if needed. The NRC expects that, generally, the information that it needs to perform its review of the DC application from a PRA perspective is that information that will be contained in applicants’ FSAR Chapter 19. 19.0-7 Draft Revision 3 – September 2012 C. Prior to the revision to 10 CFR Part 52 in August 2007, regulations required DC applicants to separately submit their PRAs. As a result, Chapter 19 of the design-specific DCDs submitted before the issuance of this rule revision did not