Approved 10/27/97 REQUIREMENT F. Violation/Inadequate Procedures Off-Normal (3) Incorrect maintenance (including calibration) on or unauthorized modifications to Safety Significant SSC required to be operable or in operation. INTERPRETATION Clarify the phrase "required to be operable or in operation" in Criteria 1.F.ON(3). Intent: Equipment that is "operable or in operation" is either physically operating, or in a standby condition and will operate upon automatic or manual demand, such as diesel generator systems. Additional Information: The authorization bases (usually the TSRs) contain requirements for equipment operability based on the plant conditions/facility status. Some safety significant SSC may not be required to be operable or in operation when a facility or process is shutdown. If the event occurs when the SSC is not required to be operable or operating due to the facility condition, then this reporting threshold is not met. For example, a facility has three identical pumps that are categorized as safety significant SSC. When the facility is operating, the TSRs require that one pump is running and another is in standby (i.e., it would start automatically if the running pump fails, as indicated by a drop in system pressure). The third pump is deenergized and isolated. Normal operating practice at the facility is to rotate the pumps on a monthly basis. In other words, the standby pump is now started, the running pump is now deenergized and isolated, and the third pump is placed in a standby condition. For this situation one pump is always in operation, one is always operable, and one is inoperable. The status of each individual pump changes monthly. Incorrect maintenance on or unauthorized modifications to the deenergized pump is not reportable under this criteria. Incorrect maintenance on or unauthorized modifications to the running or standby pump is reportable. In a shutdown condition, the TSRs require that the same three pumps be deenergized and tagged out to prevent over pressurizing the system. In this case, all three pumps are inoperable and thus reporting under this criteria is not required. |
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