A reduced pressure zone device, otherwise known as a RPZ or RPZD, is a type of backflow preventer used to guard against the polluting effects of backflow in your sewer, irrigation and water system.  Annual RPZ testing is required for most major metropolitan areas, so make sure you turn to professional, certified and licensed RPZ

A RPZ refers to a reduced pressure zone and applies in any discussion about reduced water pressure situations in a disruption of the water supply.  Where a RPZ occurs, a RPZD, or reduced pressure zone device, is needed to prevent back pressure, or back-siphonage, from occurring. A RPZ is a redundant design, providing several safety