Document: NUREG-0800
Document ID: e32f0820-4e33-476e-aa36-4ca8c2c64af0
Document Type: srp
Title: Use of Probabilistic Risk Assessment in Plant-Specific, Risk-Informed Decisionmaking:
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0119/ML011940192.pdf
Revision Date: 2023-06
Chapter: 19
Section ID: 19.0
CFR Part: 
CFR Title: 

Content:
ction provides guidance to assist reviewers in making this determination. For consistency, Sections Il1.1 through 111.4 present this guidance in terms of the four elements of the approach described in Section 2 of RG 1.174. 111.1 Element 1: Define the Proposed Change In this element, reviewers should verify that the submittal provides enough information to meet the staff's expectation that all potential safety impacts have been identified and evaluated. In addition, reviewers should be satisfied that, where appropriate, the licensee has identified design and operational aspects of the plant related to the change request that should be enhanced consistent with an improved understanding of their safety significance based on the methodology used to support the proposed relaxation in regulation. These enhancements should be appropriately reflected in changes to the plant's LB (e.g., technical specification, license conditions, and FSAR). Reviewers must also assess the proposed changes as they relate to the plant's LB, which specifies how the licensee satisfies certain basic regulatory requirements such as diversity, redundancy, defense-in-depth, and the General Design Criteria. This assessment should include reviewing the engineering (or other pertinent) analysis and data that identify the safety margins, and plant design and/or activities conducted to preserve those margins. If exemptions from regulations or other forms of relief are needed to implement the licensee's proposed change, reviewers should ensure that the appropriate requests accompany the licensee's submittal. Reviewers should also verify that the licensee has identified and appropriately used available information reflecting traditional engineering concepts and principles. Among the non-PRA sources of information that should be examined to support the evaluation of safety significance include the safety insights developed in licensing documents such as the FSAR, as well as the bases for the plant's