(a) Protective Devices in General. The owner or occupant of every premise receiving water supply shall apply and maintain suitable means of protection of the premise supply, and all appliances, against damage arising in any manner from the use of the water supply, variation of water pressure, or any interruption of water supply. Particularly, such owner or occupant must protect water-cooled compressors for refrigeration systems by means of high and/or low pressure safety cutout devices. There shall be provided means for the prevention of the transmission of water ram or noise of operation of any valve or appliance through the piping of their own or adjacent premises.
(b) Relief Valves. On all "closed systems" (i.e., systems having a check valve, pressure regulator, or reducing valve, water filter or softener) an effective pressure relief valve shall be installed at or near the top of the hot water tank, or on the hot water distribution pipe connection to the tank. No stop valve shall be placed between the hot water tank and the relief valve or on the drain pipe. (See applicable plumbing codes).
(c) Air Chambers. An air chamber or approved shock absorber shall be installed at the terminus of each riser, fixture branch, or hydraulic elevator main for the prevention of undue water hammer. The air chamber shall be sized in conformance with applicable local plumbing codes. Where possible, the air chamber should be provided at its base with a valve for water drainage and replenishment of air.