GDC 54 Piping Systems Penetrating Containment
“Piping systems penetrating containment: Piping systems penetrating primary reactor containment shall be provided with leak detection, isolation, and containment capabilities having redundancy, reliability, and performance capabilities which reflect the importance to safety of isolating these piping systems. Such piping systems shall be designed with a capability to test periodically the operability of the isolation valves and associated apparatus and to determine if valve leakage is within acceptable limits.”
The industry standard ANSI/ANS N260 (1976)  addresses the requirements of GDC 54 to GDC 57 related to the containment isolation provisions for fluid systems. The NRC staff has endorsed these provisions in RG 1.141  with certain additional provisions. In combination, the standard and the RG provide adequate requirements that the piping system penetrating containment are designed with capability to periodically test the operability, and acceptability of valve leakage.