ASSE (PLUMBING) 1056-2013 Performance Requirements for Spill Resistant Vacuum Breaker Assemblies
: Brown Technical Book Store
Spill resistant vacuum breaker assemblies are installed in the water supply lines to prevent the backflow of non-potable material into the potable water supply caused by backsiphonage only. They are not for use in any system where backpressure is applied to the assembly. When the system is pressurized, the air inlet valve closes to prevent a flow through the check valve and to eliminate vent spillage. The assembly shall: Not be subjected to backpressure; and Be installed with its critical level (CL) not less than 12 inches (305 mm) above the flood level rim of the fixture or appliances served. In the absence of a critical level (CL) mark on an assembly, the extreme bottom of the body casting shall be considered the critical level of the assembly for testing and installation purposes.