Document: NUREG-0800
Document ID: 643ab154-682e-480f-a57b-a5fd7390a34e
Document Type: srp
Title: REVIEW OF TRANSIENT AND ACCIDENT ANALYSIS METHODS
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0535/ML053550265.pdf
Revision Date: 2023-06
Chapter: 15
Section ID: 15.0.2
CFR Part: 
CFR Title: 

Content:
gular uncertainty statement is accomplished when the individual uncertainty contributions are determined (see Regulatory Guide 1.157, Ref. 10). For other events, a complete uncertainty analysis is not required. However, in most cases the SRP guidance is to use “suitably conservative” input parameters. This suitability determination may involve a limited assessment of biases and uncertainties. The individual uncertainty (in terms of range and distribution) of each key contributor is determined from the experimental data, input to the nuclear power plant model, and the effect on appropriate figures of merit evaluated by performing separate calculations. The figures of merit and devices chosen must be consistent. The NRC has developed the Code Scaling, Applicability, and Uncertainty (CSAU) methodology for code uncertainty evaluation. The CSAU process has been demonstrated for LBLOCA [Refs. 4 and 5] and boiling-water reactor ATWS [Ref. 11]. Other methods of uncertainty evaluation may be acceptable. f. Quality Assurance Plan The reviewers should confirm that the evaluation model is maintained under a quality assurance program that meets the requirements of Appendix B to 10 CFR Part 50. As a minimum, the program must address design control, document control, software configuration control and testing, and corrective actions. The reviewers should confirm that the quality assurance program documentation includes procedures that address all of these areas. The reviewers may conduct an audit of the implementation of the code developer’s quality assurance program. The reviewers should confirm that independent peer reviews were performed at key steps in the evaluation model development process. The peer review team should include programmers, developers, end users, and independent members with recognized expertise in relevant engineering and science disciplines, code numerics, and computer programming. Expert peer review team members, who were not directly involved in the