Hose connection vacuum breakers provide protection of the potable water supply against pollutants or contaminants that can enter the system through backpressure equal to the force created by an elevated hose from 6.0 inches (15.2 cm) to 10.0 feet (3.0 meters) in height and backsiphonage through the hose threaded outlets.

This standard applies only to those devices which are designed to be installed on the discharge side of the hose bibb, hydrant, or faucet which is fitted with hose threads. The design embraces a check valve member force loaded, or biased, to a closed position, and an atmospheric vent valve, force loaded, or biased, to an open position when the device is not under pressure. This device shall not be subjected to more than twelve (12) hours of continuous water pressure. This device shall only be used on systems where the only source of low head back pressure comes from an elevated hose equal to or less than 10.0 feet (3.0 meters) in height.