(1)
Every direct flush valve shall
(a)
open fully and close positively under service pressure,
(b)
complete their cycle of operation automatically,
(c)
be provided with a means of regulating the volume of water that they discharge, and
(d)
be provided with a vacuum breaker unless the fixture is designed so that back-siphonage cannot occur, and
(e)
conform to ASSE 1037 / ASME A112.1037 / CSA B125.37, “Performance requirements for pressurized flushing devices for plumbing fixtures.”