(1) Tire utility shall test each pressure-relief valve in place within aperiodic interval of not more than three months to determine whether it has sufficient capacity to limit the pressure on the facilities to which it is connected to the desired maximum pressure.

(2) Where the test is not feasible, a pressure-relief valve shall be tested by the utility by calculating the required capacity of the relieving equipment at each station and comparing the results with the rated or experimentally determined relieving capacity of the installed equipment for the operating conditions under which it works.

(3) If it is determined that tire relieving equipment is of insufficient capacity, it shall be replaced with equipment that has the adequate capacity or further equipment may be installed to provide the required capacity.