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:
n and/or review), or changes may be combined as risk tradeoffs (balancing risk increases with risk decreases). Changes grouped in this way should normally be related, for example by affecting the same single system or activity, the same safety function, or the same accident sequence group, or by being of the same type (e.g., changes in AOT). However, this does not preclude unrelated changes from being accepted. When combined change requests are submitted, the staff should conduct a detailed assessment of the relationship between the individual changes and how they have been modeled in the risk assessment. In its review, the staff should evaluate the acceptability of the individual changes and the overall impact of the combined changes with respect to the principles and expectations discussed in Section II of this SRP Chapter 19. Section III.2.3 discusses the review of combined change requests in more detail. III.2 Element 2: Conduct Engineering Evaluations In order to make findings regarding the acceptability of a proposed license amendment, the staff should establish its position on the basis of an integrated assessment of traditional engineering evaluations and probabilistic information. Section 2.2 of Regulatory Guide 1.174 describes the specific evaluations that the licensee is expected to perform. The scope and quality of the engineering analyses conducted to justify a proposed change should be appropriate for the nature and scope of that change. Section 3 of Regulatory Guide 1.174 describes the various types of traditional engineering and probabilistic information that should be included in submittals. The results of this element should be reviewed to determine if the submittal satisfies the following principles for risk-informed decisionmaking: the proposed change meets current regulations (unless the change is explicitly related to a requested exemption or rule change); the defense-in-depth philosophy is maintained; sufficient safety margins are maintained;