What types of Backflow Prevention devices are there?
There are testable devices such as Reduced Pressure Zone Devices (RPZD) or Registered Air Gaps (RAG) for high hazard areas, Double Check Valves (DCV) for medium hazard areas and non-testable Dual Check Valves for low hazard areas. The hazard ratings for potential cross-connection situations are specified in the Australian Standards, AS/NZS 3500.
