What is a pressure vacuum breaker (PVB) assembly?
A PVB assembly is a mechanical preventer that consists of an independently acting, spring-loaded check valve and an independently acting, spring-loaded, air inlet valve on the discharge side of the check valve. It includes shutoff valves at each end of the assembly and is equipped with test cocks. A PVB may be used to isolate health or non- health hazards, but is effective against backsiphonage only.
