Backflow Testing

Three things about this subject are true, checkable in one free federal document, and almost never said out loud.

Key point

EPA separates containment at the service connection from fixture protection inside a building, and the assembly a property is required to test annually is almost always the first kind. It faces outward: it exists so that whatever is inside the building cannot reach the public main.

Source: U.S. EPA, Cross-Connection Control Manual, EPA 816-R-03-002, February 2003.

CrossConnect is a referral service, not a contractor. We connect property owners and managers with independent contractors. Backflow assembly testing is normally restricted to testers holding a specific certification and using calibrated equipment, and the report usually has to reach your water purveyor — ask to see the certification and ask who files the report. We carry out no testing, we certify nobody, we do not set prices, and we never charge callers anything. Nothing here selects a device for any installation or states that any assembly is passing.

One: the assembly faces outward

The manual names the service connection as the primary containment point, and it separates that from the fixture protection fitted inside a building. The assembly at the boundary is installed to keep hazards inside the premises out of the public system.

So the annual test is not a fee on your own water. It is a check on the thing standing between your premises and everybody else’s. Which changes how the whole obligation reads.

Source: U.S. EPA, Cross-Connection Control Manual, EPA 816-R-03-002, February 2003.

Two: there are two kinds of backflow and most devices stop one

Backsiphonage is the supply falling to a vacuum and atmospheric pressure pushing something into it. Backpressure is a connected system at a higher pressure forcing something in against a supply that is working normally.

Atmospheric and pressure vacuum breakers address backsiphonage and are not for backpressure. A device chosen against one event gives no protection against the other. The distinction, and what each family is approved for.

Three: the strongest protection has no moving parts

An air gap must be twice the supply pipe diameter and never less than one inch. Nothing to stick, nothing to corrode, no test kit — and EPA still requires that air gaps be inspected as often as mechanical preventers, because the thing that ruins one is a person.

Two numbers and a ruler, and the version of this that is probably true in your own yard.

And it is not hypothetical

85–90 psi against 65–70 psithe pressure difference in a documented incident that put about 2,000 cubic feet of propane into an 8-inch public water main

EPA’s manual records case histories rather than warnings: a funeral home aspirator, sodium hydroxide backsiphoned during a main break with water measured at a pH as high as 13, and the propane above. All three, and what they have in common.

What we will not tell you

Which device your installation needs, how often yours must be tested, or whether an assembly is passing. The first is a hazard assessment, the second is your purveyor’s program, the third is a measurement with a calibrated gauge.

That refusal has its own page, along with the price and anything at all about the water itself.

The service itself

We connect property owners and managers with independent contractors who cover their area, and the contractors pay us when we route them a call. You are never charged.

How that works in full, and where we route.

Every page here

Know what is on the tag before you call.Make, model, size and the date of the last test are usually stamped or tagged on the assembly itself, and they decide which test kit and which paperwork the visit needs. We will route you to somebody who covers your area, selected on the ZIP code of the property, and you are never charged. Backflow is our specialty, though the number will take any plumbing request on the property.

Call (888) 764-9890