Document: NRC Regulatory Guide
Document ID: 47b09be1-4bf8-45f9-a099-7fed871c09bd
Document Type: regulatory_guide
Title: Plant-Specific, Risk-Informed Decisionmaking: Inservice Testing (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML2114/ML21140A055.pdf
Revision Date: 2023-05
Chapter: 
Section ID: RG-1.175
CFR Part: 
CFR Title: 

Content:
for all applications RG 1.175, Page 5 such as IST (this guide), inservice inspection, and technical specifications. However, licensees may propose other approaches for consideration by the NRC staff. This revision does not provide guidance on preparing a request to use an RI-IST program for snubbers; however, the NRC staff will consider requests such requests if submitted. Key Principles of Risk-Informed Integrated Decisionmaking In risk-informed decisionmaking, risk-informed changes to an IST program are expected to meet a set of key principles as applicable to an alternative request in accordance with 10 CFR 50.55a(z)(1). Some of these principles are written in the terms typically used in deterministic engineering decisions (e.g., defense-in-depth), which are not directly applicable to a 10 CFR 50.55a(z)(1) alternative request. Although the principles are written in these terms, the use of risk analysis is encouraged to help ensure and to show that these principles are met. These principles include the following: • Principle 1: The proposed licensing-basis change meets the current regulations unless it is explicitly related to a requested exemption (i.e., a specific exemption under 10 CFR 50.12, “Specific Exemptions”). • Principle 2: The proposed licensing-basis change is consistent with the defense-in-depth philosophy. • Principle 3: The proposed licensing-basis change maintains sufficient safety margins. • Principle 4: When proposed licensing-basis changes result in an increase in risk, the increase should be small and consistent with the intent of the Commission’s policy statement on safety goals for the operations of nuclear power plants. • Principle 5: The impact of the proposed licensing-basis change should be monitored using performance measurement strategies. Each of these principles should be considered in the risk-informed, integrated decisionmaking process, as illustrated in Figure 1. RG 1.174 gives additional guidance on the key