(a) Scope. This section sets forth requirements for the periodic maintenance of pressure tanks that supply water to sprinkler systems.
(b) General Provisions. Water tanks that supply water to sprinkler systems shall be maintained in compliance with the requirements of FC901.6, NFPA 25, and this section.
(c) Periodic Maintenance Requirements. Sprinkler system pressure tanks shall be inspected and tested at least monthly by a certificate of fitness holder and if necessary, corrective action taken, in accordance with the following procedure:
(1) Close both the top and bottom valves on the sight glass level gauge.
(2) Open the petcock at the bottom of the gauge glass and drain the water out of the glass by cracking the top valve to clear the glass. Close the petcock. Open the top valve and allow air to enter the glass.
(3) Open the bottom valve to allow water to enter the gauge glass. Open the top valve.
(4) When the air and water levels stabilize, the level should be at the 2/3 level or the level required for the design of the system. Immediate corrective action shall be taken in the event the water level is below the design level.
(5) If the water level is too high, drain water using the emergency valve on the tank. After draining to the design level, introduce compressed air into the tank until the design air pressure is obtained.
(d) Notification of Central Station. If the sprinkler system pressure tank is monitored by a central station, the central station company shall be notified before any testing is conducted.