Pressurized water reactor designs preclude full-flow testing of certain safety-related standby pumps during power operations. This is problematic for Group B pumps that test in the alert range under comprehensive pump test conditions that are only available during refueling outages. The ASME OM committees sought to resolve this issue when new provisions were added to ISTB-6200 in ASME OM-2012. The provisions allow analysis of pump performance in lieu of testing at an increased frequency. Palo Verde Generating Station employed these rules to satisfy OM requirements for a vibration alert range entry of its high pressure safety injection pump without having to submit for regulatory relief or shut down to perform the test. The changes to ISTB-6200 in ASME OM-2012 give plants the flexibility to ensure safe operation without undergoing extraordinary measures to accommodate testing requirements.

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