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:
ndition (e.g., improve testing practices, repair or replace the component). The root cause of failure should be determined for all components categorized as having high safety significance, as well as for components categorized LSSC when the apparent cause of failure may contribute to common cause failures. * Assess the applicability of the failure or nonconforming condition to other components in the IST program (including any test sample expansion that may be required for grouped components such as relief valves). * Correct other susceptible similar IST components as necessary. * Consider the effectiveness of the component's test strategy in detecting the failure or nonconforming condition. Adjust the test frequency or methods or both, as appropriate, when the component (or group of components) experiences repeated or age-related failures or nonconforming conditions. The corrective action evaluations should periodically be given to the licensee's PRA group so that any necessary model changes and regrouping are done as might be appropriate. The effect of the failures on overall plant risk should be evaluated and the fact that the corrective actions taken will restore the plant risk to an acceptable level should be confirmed. The RI-IST program documents should be periodically revised to record any RH-IST program changes resulting from corrective actions taken. 4. Periodic Reassessment The test strategy for IST components should be periodically assessed to reflect changes in plant configuration, component performance, test results, and industry experience. 5. RO-ST Program Changes After Initial Approval Licensees can change their RI-IST programs consistent with the process (i.e., as defined in the RI-ST Program Description) and results that were reviewed and approved by the NRC staff. As discussed in Section V below, the overall RI-IST program, including changes thereto, are enforceable under 10 CFR 50.55a. Examples of changes to RI-IST programs that would not