Document: NUREG-0800
Document ID: dd4f84a9-8976-44c4-b631-d7c0254f4efc
Document Type: srp
Title: PROBABILISTIC RISK ASSESSMENT AND SEVERE ACCIDENT EVALUATION FOR
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML1416/ML14161A594.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19.0
CFR Part: 
CFR Title: 

Content:
iteria given in Section II of this SRP. 2. Staff responsible for the review of the seismic and structural design of the facility review (1) the applicant’s evaluation of seismic fragilities, and (2) the applicant’s determination of plant-level HCLPF in accordance with the acceptance criteria given in Section II of this SRP. The staff reviewing the plant system and accident sequence analysis verifies that the applicant has considered random equipment failures, seismic interactions, as well as operator actions in the plant system and accident sequence analysis as applicable. It is important that the plant systems analysis focus on those sequences leading to core damage or containment failures, including applicable sequences leading to the following containment failures: (1) loss of containment integrity, (2) loss of containment isolation, and (3) loss of function for prevention of containment bypass. The applicant should address the following operating modes in the analysis: (1) at power (full power), (2) low power, and (3) shutdown. Design-Specific PRA (Treatment of Internal Fires) 1. The reviewer considers the extent to which applicant’s assessment of the risk associated with internal fires conforms to the guidance in either NUREG/CR-6850 (EPRI 1011989), “Fire PRA Methodology for Nuclear Power Facilities,” issued September 2005 or EPRI TR-100370, “Fire-Induced Vulnerability Evaluation (FIVE),” EPRI, April 1992. The FIVE methodology is considered to be a simplified method suitable for identifying fire vulnerabilities and performing screening evaluations. The NRC considers the NUREG/CR-6850 approach to be a state-of-the-art fire risk analysis approach because methodological issues raised in past fire risk analyses, including individual plant examination of fire analyses, have been addressed in NUREG/CR-6850 to the extent allowed by the current state-of-the-art. NUREG/CR-6850 is therefore considered to be a preferable method for performing fire PRA to