ASSE (Plumbing) 1047-2009

This standard applies to the type of assembly identified as Reduced Pressure Detector Fire Protection Backflow Prevention Assemblies (RPDF). This assembly consists of two (2) independently-acting check valves, internally force loaded to a normally closed position, and separated by an intermediate chamber (or zone) in which there is a hydraulically operated relief means for venting to atmosphere, internally force loaded to a normally open position. These assemblies are designed to operate under continuous pressure conditions. This standard also applies to Manifold Reduced Pressure Fire Protection Backflow Prevention Assemblies. They consist of two or more complete RPDF assemblies in parallel. The assemblies do not need to be of the same pipe size.