What is a key feature of a reduced pressure zone (RPZ) device?

A key feature of a reduced pressure zone (RPZ) device is its ability to prevent backflow by maintaining a pressure differential. This device is specifically designed to protect the water supply from contamination that can occur when there is a backflow event.

The RPZ operates with two check valves and a pressure differential relief valve, which works together to ensure that the pressure in the system is always lower than the pressure in the external water source. This maintains a negative pressure zone that prevents any potentially contaminated water from flowing back into the clean water supply, especially during events that could lead to backpressure or backsiphonage.

This design is crucial in situations where the water supply may be at risk due to industrial processes, chemical use, or other contaminants that could pose a health hazard. The RPZ's ability to maintain this pressure differential makes it one of the most reliable backflow prevention methods available, allowing it to effectively mitigate the risk of backflow under various conditions.