When it comes to protecting your backflow assembly, there’s a right way and a wrong way. Choosing the right way means offering the most complete protection you can provide your water supply and your employees. Installing your backflow prevention assembly improperly exposes it to unnecessary flooding risks. Here’s why:

Why is Protecting an RPZ Important?

A commercial building or industrial plant can use all the water it wants, but once the water has passed through the meter and the backflow preventer, it will not be allowed back into the water supply.

An RPZ provides the best level of protection because it has a built-in relief valve, which will open up and actually dump the backflowing water out of the valve, in order to prevent any chance of contaminated water re-entering the water supply. 



Reduced Pressure Zone (RPZ) valve assemblies, on the other hand, provide the highest level of protection for your water supply.

There is one critical difference between an RPZ and a DC: RPZs are designed to dump water to protect the water system.

An RPZ uses two independently operating check valves, just like the DC valve assembly. But it’s also equipped with a hydraulically-operated differential relief valve that’s located below the first check valve.

This hydraulic valve (and its strategic placement) makes the RPZ virtually fail-safe because when the zone of pressure is compromised, the relief valve opens, and the water is expelled. Since it is virtually impossible for contaminants to backflow through an RPZ valve, they are trusted for maximum protection of the water supply.


Since RPZ valve covers provide the best barrier between backflow and your water supply, it deserves the highest level of protection you can provide. When it’s working properly, it floods the surrounding area, so an RPZ is better off in an enclosure outside the building.

In fact, RPZs offer so much peace of mind, many jurisdictions are now requiring their use on all domestic and fire service lines. And when it comes to installing RPZs, you essentially have two options: inside in a mechanical room (which exposes you to unnecessary flooding risks), or in an RPZ enclosure.

If you are an architect or design engineer, you’ll want your project to benefit from your good decision making. So don’t take the risk of installing the RPZ inside the building. Moving the RPZ outside and protecting it with an above-ground RPZ enclosure is your best option.

Get started by talking to one of our experts. They’ll take your exact measurements and put together a Reduced Pressure Zone Assembly or Double-Check Backflow Assembly enclosure that’s perfect for you.