Document: NUREG-0800
Document ID: ac43f632-9db1-4857-9f56-bfba45965456
Document Type: srp
Title: * These are modifications to a plant’s design, operations, or other activities that require NRC approval. These modifica
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0232/ML023250195.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19
CFR Part: 
CFR Title: 

Content:
fected by the issue being evaluated. This includes (1) identifying the specific PRA contributors for the particular application, (2) assessing the portions of the model that should be modified for the application, and (3) identifying supplemental analyses that could be used to support the application. This approach will help reviewers determine the scope and level of detail of analysis required for the remaining steps in the change process. SRP 19-14 Table III-1 of this SRP chapter summarizes the general guidance for use in identifying elements of the PRA model that may be affected by an application. This guidance, presented as a list of questions, will assist reviewers in establishing a cause-effect relationship between the application and the PRA model. The answers to these questions should be used to identify the extent to which the proposed change affects the design, operation, and maintenance of plant SSCs. Reviewers should also verify that the effects of the proposed changes on plant elements (SSCs, operator actions, etc.) are adequately characterized in the elements of the PRA model or by appropriate changes to the logic model structure. For full-scale applications of the PRA, for example, this should be reflected in a quantification of the impact on the PRA results. For applications like component categorization, however, sensitivity studies on the effects of the change may be sufficient. Similarly, for other applications, it may be adequate to define the qualitative relationship of the impact on the PRA elements, or it may simply be necessary to identify which elements are impacted. The review procedure for this element is therefore intended to verify that the submittal appropriately accounts for the effects of the changes on SSC reliability and unavailability or on operator actions. Where applicable, reviewers should also evaluate the modeling and quantification of the effects of the change to ensure that the models are appropriate and that the results can