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:
d test intervals are less than the expected time to failure of the components in question. In addition, the reviewer should spot check the licensee's calculations or basis for concluding that adequate component capability exists, above that required during design basis conditions, so that component operating characteristics over time do not lead to a point of insufficient margin before the next scheduled test activity. The reviewer should verify that the IST intervals are not extended beyond once every 6 years or beyond three refueling outages (whichever is longer) without specific compelling documented justification. Extensions beyond 6 years or beyond three refueling outages should be considered as component performance data at extended test intervals is acquired. 2 Unless the technical adequacy of the licensee's proposal is dependent upon the affected commitment determined to be unacceptable, the Staff reviewer should prepare either: (i) a backfit analysis showing that imposition of the commitment will constitute a cost-justified substantial increase in protection to public health and safety, or (ii) a "documented evaluation" demonstrating that one or more of the exceptions in Section 50.109(a)(4) have been met. 3.9.7-1 7 Rev. 0 -August 1998 The reviewer should verify that the licensee made a commitment to adopt enhanced test strategies as described in the risk-informed IST Code Cases developed by ASME, as endorsed by the NRC. If the licensee chooses not to adopt one or more of these Code Cases (or if such a Code Case is unavailable, the reviewer should examine the licensee's written technical justification outlining why it is impractical to implement the risk-informed Code Case strategy and should assess the adequacy of the licensee's proposed alternative test strategy. The reviewer should verify that the licensee's RI-IST program identifies and tests components categorized HSSC that are not in the licensee's current IST program commensurate with their safety