Section 193.2619 - Control systems(a) Each control system must be properly adjusted to operate within design limits.(b) If a control system is out of service for 30 days or more, it must be inspected and tested for operational capability before returning it to service.(c) Control systems in service, but not normally in operation, such as relief valves and automatic shutdown devices, and control systems for internal shutoff valves for bottom penetration tanks must be inspected and tested once each calendar year, not exceeding 15 months, with the following exceptions: (1) Control systems used seasonally, such as for liquefaction or vaporization, must be inspected and tested before use each season.(2) Control systems that are intended for fire protection must be inspected and tested at regular intervals not to exceed 6 months.(d) Control systems that are normally in operation, such as required by a base load system, must be inspected and tested once each calendar year but with intervals not exceeding 15 months.(e) Relief valves must be inspected and tested for verification of the valve seat lifting pressure and reseating.Amdt. 193-2, 45 FR 70407, Oct. 23, 1980, as amended by Amdt. 193-17, 65 FR 10960 , Mar. 1, 2000