Abstract: The present disclosure pertains to a system configured to protect flows in piping systems using minimal spare components. Some embodiments may provide: a first piping subsystem configured to receive a portion of the input flow; a second piping subsystem configured to receive the portion of the input flow by substituting for the first subsystem; a test subsystem configured to detect whether each of the first and second subsystems is able to vent when at least one, in the each subsystem, of a respective pressure and a respective pressure rate satisfies first and second criteria, respectively; and first and second pilots configured to detect a maximum pressure and a maximum pressure rate, respectively, of the portion of the first and second subsystems.