A self-revealing
NCV was identified for an inadequate tagging procedure that resulted in a failure to properly isolate a fire hydrant before maintenance. Because of the failure, the hydrant was forced off the associated fire protection system
header, depressurized the system, and rendered it
inoperable. The licensee entered the problem into their corrective action program and initiated actions to prevent recurrence. This finding was more than minor because it affected the mitigating system cornerstone objective of availability of systems, i.e. Fire Protection System, and was associated with the protection against fire, an external hazards attribute. While the finding caused the fire protection system to be
inoperable, the inspectors determined that the degradation rating used for the
significance determination process was low. Therefore, the finding was considered to be of very low safety significance. The cause of the finding was associated with the accurate and up-to-date procedures and work packages aspect of the human performance cross-cutting area. The clearance procedure and Work Order (
WO) were not sufficient to ensure continued fire protection system operability during hydrant maintenance
