BACK-FLOW PREVENTION DEVICES & TESTER LIST
Commonly Used Backflow Prevention Devices
The three most common and effective devices installed to prevent backflow are shown below:
Used mainly on tanks and sinks, it is a gap between the outlet and the basin.
- The gap needs to be a minimum two times the supply pipe diameter.
Pressure Vacuum Breaker
Used mainly on lawn irrigation systems. It has a one way check and a spring loaded air inlet valve that closes when water pressure drops.
- No backpressure (from fertilizer injection system or water well)
- 12" above highest sprinkler head
- Protect from freezing
Reduced Pressure (RP) Principle Assemblies
A reduced pressure principle assembly is a mechanical valve assembly that consists of two internally loaded independently operating check valves and a mechanically independent, hydraulically dependent relief valve located between the check valves.
It is used for services that have either health hazards or non-health hazards and under conditions of backpressure or backsiphonage. It provides the highest level of protection among the mechanical backflow prevention devices.Cross Connection Control Pro