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:
fication of the success criteria? • Does the modification of success criteria necessitate changes in other criteria, such as system interdependencies? Event Trees • Does the application address an issue that can be associated with a particular branch or branches on the event trees, and if so, is the branching structure adequate? • Does the application necessitate the introduction of new branches or top events to represent concerns not addressed in the event trees? • Does the application necessitate consideration of reordering branch points (i.e., does the application affect the sequence-dependent failure analysis)? System Reliability Models • Does the application impact system design in such a way as to alter system reliability models? • Does the application impact the support functions of the system in such a way as to alter the dependencies in the model? • Does the application impact the system performance and, if so, is that impact obscured by conservative modeling techniques? Parameter Database • Can the application be clearly associated with one or more of the basic event definitions, or does it necessitate new basic events? • Does the application necessitate a specialized probability model (e.g., time-dependent model)? • Does the application necessitate modifications to specific parameter values? • Does the application introduce new component failure modes? • Does the application affect the component mission times? • Does the application necessitate that the plant-specific (historical) data be taken into account, and can this be easily achieved by an update of the previous parameters? • Does the application involve a change that may impact parameter values, and do the present estimates reflect the current status of the plant with respect to what is to be changed? Dependent Failure Analysis • Does the application introduce or suggest new common cause failure contributions? • Does the application introduce new asymmetries that