RPZ High Hazard Backflow Prevention

Reduced Pressure Zone Backflow Preventers are devices that protect the water supply from contamination from substances that, if ingested, could be harmful to human health.

Many piping arrangements directly connect a source of harmful substances to drinking water piping. This piping is required by state and federal law to be protected from any possible backflow.

For example, homes with central heating boilers have a fill valve to add water to the boiler as needed. That fill valve could be opened when there is low or negative pressure in the water supply lines, such as when the house or city water main is off for maintenance, or when a fire truck is pulling water out through a nearby hydrant.