Backflow Preventor Testing
BACKFLOW PREVENTOR TESTING
Air Excellence provides licensed backflow testing services for the commercial, industrial and mining sectors.
Backflow – It’s just what it sounds like: the water is flowing in the opposite direction from its normal flow. A change in pressure within the drinking water source can cause a backflow, allowing contaminants to enter our drinking water system through cross-connections. There are two types of backflow: back-siphonage (caused by low pressure in the drinking water supply) and back pressure (when a pump, elevated tank or piping, boiler, or other means on the consumer’s side of the service connection has a greater pressure).
Without proper protection devices, something as useful as your garden hose has the potential to poison your buildings water supply.
PREVENTION
There are three easy ways you can prevent backflow at a cross connection:
- Never place the end of a hose where it can suck contaminants into your drinking water,
- Leave at least a one-inch gap between the end of a hose and a source of contamination (called an air gap), and
- Use a proper backflow protection device.
An air gap is a vertical, physical separation between the end of a water supply outlet and the flood-level rim of a receiving vessel. This separation must be at least twice the diameter of the water supply outlet and never less than one inch. An air gap is considered the maximum protection available against backpressure backflow or back-siphonage but is not always practical and can easily be bypassed.
BACKFLOW PREVENTION DEVICES
Each spigot on your property should have a hose-bib vacuum breaker installed. This is a simple, inexpensive device that can be purchased at any plumbing or hardware store. Installation is as easy as attaching your garden hose to a spigot. It’s important to test all backflow devices annually to ensure they are functioning properly.
Mechanical backflow preventers have internal seals, springs, and moving parts that are subject to fouling, wear, or fatigue. Also, mechanical backflow preventers and air gaps can be bypassed. Therefore, all backflow preventers have to be tested periodically to ensure that they are functioning properly. A visual check of air gaps is sufficient, but mechanical backflow preventers must be tested annually by a licensed backflow tester with properly calibrated gage equipment.