Document: NRC Regulatory Guide
Document ID: 6f84e3bf-9ff3-49fb-a16a-0de3b89e6bc6
Document Type: regulatory_guide
Title: An Approach for Plant-Specific Risk-Informed Decisionmaking for Inservice Inspection of Piping (Rev. 2)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2103/ML21036A105.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.178
CFR Part: 
CFR Title: 

Content:
les described in this guide and in RG 1.174. RG 1.174 provides general guidance for performing this evaluation, which is supplemented by the RI-ISI guidance herein. The discussions below summarize the regulatory issues and engineering activities that should be considered for RI-ISI programs, divided, for simplicity, into deterministic and PRA analyses. Section C.2.1 addresses the deterministic engineering analysis, Section C.2.2 addresses the PRA-related analysis, and Section C.2.3 describes the integration of the deterministic and PRA analyses. In reality, many facets of the deterministic and PRA analyses are iterative. The engineering evaluations should do all of the following: a. Demonstrate that the proposed change is consistent with the defense-in-depth philosophy. b. Demonstrate that the proposed change maintains sufficient safety margins. c. Demonstrate that, when proposed changes result in an increase in risk, the increases should be small and consistent with the intent of the Commission’s policy statement on safety goals for the operations of nuclear power plants. RG 1.178, Page 11 d. Support the integrated decisionmaking process. The scope and quality of the engineering analyses performed to justify the changes proposed to the ISI programs should be appropriate for the nature and scope of the change. The following subsections present the decision criteria associated with each key principle identified above. The licensee can propose equivalent criteria if such criteria can be shown to meet the key principles set forth in Section C of RG 1.174. 2.1 Engineering Analysis The licensee should consider the appropriateness of qualitative and quantitative analyses, as well as analyses using traditional engineering approaches and those techniques associated with the use of PRA findings. Areas to be evaluated from this viewpoint include meeting the regulations, defense-in-depth attributes, safety margins, assessment of the failure potential of piping segments, and