Document: NUREG-0800
Document ID: 4e1d86bd-74a5-4678-8bc0-ffce3ba28ea0
Document Type: srp
Title: RISK-INFORMED INSERVICE TESTING
Source: NUREG-0800
Source URL: https://www.nrc.gov/docs/ML0428/ML042880272.pdf
Revision Date: 2023-06
Chapter: 3
Section ID: 3.9.7
CFR Part: 
CFR Title: 

Content:
hose non-code components that the licensee's integrated decision-making process categorized as HSSC. The staffs basis for reaching a conclusion that the licensee's proposed RI-IST program "provides an acceptable level of quality and safety" will be predicated, in part, on the licensee's use of PRA to identify the appropriate components that should be included in an RI-IST program. In addition, PRA insights should be used to evaluate test requirements (i.e., test methods and frequency). This will ensure that assumptions used to justify relaxations in testing requirements for components within the scope of the current ASME Code-required IST program remain valid. 3. Changes To Component Test Requirements A RI-IST program should identify components that are candidates for an improved test strategy (i.e., frequency, methods or both) as well as components for which the test strategy might be relaxed. It should also, in some cases, identify components categorized HSSC that may not be included in the present IST program. The information contained in, and derived from, the PRA should be used to help construct the testing strategy for components. To the extent practicable, components with high safety significance should be tested in ways that are effective at detecting their risk-important failure modes and causes (e.g., ability to detect failure, to detect conditions that are precursors to failure, and predict end of service life). [Note: The test described in the current ASME Code may not be particularly effective in detecting the risk- important failure modes and causes of a component or group of components. A more effective test strategy for HSSC components may be to conduct an enhanced test at an extended test interval.] Components categorized as LSSC may be tested less rigorously than components categorized as HSSC (e.g., less frequent or informative tests). In some situations, an acceptable test strategy for components categorized HSSC may be to conduct the existing