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:
ed beyond once every 6 years or three refueling outages (whichever is longer) without specific, compelling, documented justification. Extensions beyond 6 years or three refueling outages (whichever is longer) will be considered as component performance data at extended intervals are acquired. Components categorized as HSSC that are not in the licensee’s current IST program should be considered for testing as described by NRC-approved ASME risk-informed Code Cases. If the licensee does not use an OM Code testing method, the licensee should develop alternative test methods to ensure operational readiness and to detect component degradation (i.e., degradation associated with failure RG 1.175, Page 22 modes identified as important in the licensee’s PRA). At a minimum, the RI-IST program should summarize these components and their proposed testing. For components categorized as HSSC that were the subject of a previous NRC-approved relief request or an authorized alternative test, the RI-IST alternative request should discuss the appropriateness of the test method specified in the previous relief or alternative request in light of the component’s safety significance. If practical, IST components (with the exception of certain check valves and relief valves) should, at a minimum, be exercised or operated at least once every refueling cycle. More frequent exercising should be considered for components in any of the following categories, if practical: a. components with high risk significance, b. components in adverse or harsh environmental conditions, and c. components with any abnormal characteristics (operational, design, or maintenance conditions). The RI-IST program description should include the testing strategy for each component (or group of components) in the licensee’s RI-IST program. The RI-IST program description should summarize all testing to be performed on a group of components (e.g., MOV testing in response to NRC Generic Letter 96-05). The