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:
ally not detailed enough to support code assessment of specific models. Plant data can be used for code assessment if it can be demonstrated that the available instrumentation provides measurements of adequate resolution to assess the code. The assessment cases must compare code predictions to all important measured variables in order to show that good predictions of one test variable do not result from compensating errors. Assessments must include a description of all assessment cases, specific models that are being assessed in each case, and acceptance criteria used. Acceptance criteria must be supported by quantitative analysis whenever possible. ECCS evaluation models must include a specific assessment to meet the criteria in Appendix K to 10 CFR Part 50. Small-break ECCS evaluation models must also meet the assessment requirements of TMI Action Item II.K.3.30, where applicable. 5. Uncertainty Analysis The uncertainty analysis must address all important sources of code uncertainty, including the mathematical models in the code and user modeling such as nodalization. The major sources of uncertainty must be addressed consistent with the results of the accident sequence identification process. When the code is used in a licensing calculation, the combined code and application uncertainty must be less than the design margin for the safety parameter of interest. The analysis must include a sample uncertainty evaluation for a typical plant application. In some cases, bounding values are used for input parameters as described in SRP sections or Regulatory Guides and are used for plant operating conditions such as accident initial conditions, set points, and boundary conditions. 6. Quality Assurance Plan The code must be maintained under a quality assurance program that meets the requirements of Appendix B to 10 CFR Part 50. 15.0.2-7 Initial Issuance - December 2005 III. REVIEW PROCEDURES 1. Assignment of Review Responsibilities The lead reviewer for the evaluation