Backflow Prevention and Testing for Fullerton Businesses

What backflow is and why it matters

Water normally flows one way: from the city main into your building. Backflow happens when pressure changes make it flow the other way. A drop in street pressure from a main break or firefighting can siphon water back out of the building, and a pump or boiler in the building can push it back. If that water has been in contact with chemicals, irrigation, a carbonation system or a fire sprinkler line, it can contaminate the public supply.

A backflow prevention assembly is a set of check valves and relief components installed so water can only move in one direction. Because the internal parts wear and can stick, especially with hard water, the assemblies are tested periodically to make sure they still close properly.

Where commercial properties often have assemblies

On the main domestic water service to the building.
On fire sprinkler connections.
On landscape irrigation systems.
On beverage carbonation and soda systems in restaurants and bars.
On equipment fed with chemicals, such as some dish and laundry setups.
On boilers or other process connections in larger buildings.

Terms on a test report

Reduced pressure assembly (RP): An assembly with two check valves and a relief valve between them, used where the hazard is higher. It can discharge water when it relieves, so it needs a place for that water to go.
Double check assembly: Two independent check valves, used for lower-hazard connections.
Test cocks: Small valves on the assembly used to attach the tester's gauge.
Certified tester: A person certified to test backflow assemblies. The water utility may keep its own list or rules on who can test.
Test report: The form recording the results, usually submitted to the water purveyor.

How a routine test usually goes

Notice or schedule.Many properties receive a notice from the water utility; others track their own dates. Check with the City of Fullerton water utility for your requirements.
Brief shutoff.Water downstream of the assembly is shut off during the test. Plan for a short interruption.
Gauge test.The tester connects a gauge to the test cocks and checks each valve.
Repair if needed.Failed assemblies usually need parts replaced or a rebuild, then a retest.
Report.Results are submitted on the required form. Keep your own copy on file.

When something looks wrong

IfAn RP assembly is dripping or discharging from its relief portIt may be relieving as designed during a pressure change, or an internal part may be failing. Have it tested.
IfYou are adding a soda system, irrigation or chemical feedAsk a plumber whether new backflow protection is required before installation.
IfAn assembly failed its testSchedule repair and a retest promptly and keep records of both.
IfYou received a notice you do not understandCall the water utility listed on the notice and ask what it requires.

Questions to ask a backflow tester

Are you certified to test in Fullerton, and how do I confirm it?
Will you submit the report to the water utility or give it to me?
If the assembly fails, can you repair it, and what does the retest involve?
How long will water be off during the test?

Common questions

How often does backflow need to be tested?

Testing is commonly required on a regular schedule, but the exact interval and process come from the water purveyor. Check with the City of Fullerton water utility for your property.

Is backflow testing the same as a plumbing inspection?

No. It is a specific test of one device. A plumber may also be a certified tester, but not every plumber is.

Why is water coming out of our backflow device?

Reduced pressure assemblies are designed to discharge when they relieve. Frequent or continuous discharge usually means a part needs attention, so have it tested.

General information for Fullerton, not a quote or professional advice. In an emergency, call 911.