Backflow Protection Using Backflow Prevention Devices

Backflow Protection Device General Installation Requirements
1. Protect all drinking (potable) water supply openings, outlets, and connections by an air gap or by an approved backfl ow preventer. This means that any place from which water flows must have either an air gap or have a backfl ow preventer installed. Examples of openings, outlets and connections include sinks, bathtubs, showers, hose bibbs, and water supply connections to water and steam heating systems, irrigation systems, swimming pools, fountains, ponds, and similar water features.
2. Install, inspect, and maintain backfl ow preventers according to manufacturer’s instructions and the terms of the backfl ow preventer’s listing.
3. Provide access to all backfl ow preventers for inspection and maintenance.
4. Protect backfl ow preventers from freezing by heat, insulation, or by making them removable.
5. Discharge backfl ow preventer relief port to an indirect waste receptor or to the outdoors.
6. Do not connect pipes from a private well or other private water supply to pipes that are connected
to the public water supply.

Backflow Protection of Toilet Fill Valves
1. Protect toilets with an approved antisiphon fill valve.
2. Locate the backflow preventer at least (≥) 1 inch above the opening of the overflow pipe. Fill valves with all parts below the tank water line usually violate this provision.

Backflow Protection of Hose Bibbs
1. Protect water supply openings equipped with a hose connection with an approved atmospheric or pressure vacuum breaker or with a permanently attached hose connection vacuum breaker. Some hose bibbs have a vacuum breaker built in. Look for a UPC or other label on hose bibbs with a built in vacuum breaker. Some jurisdictions require a backflow preventer on laundry sink and similar faucets with hose thread connections.
2. You are not required to install a backflow preventer on water heater and boiler hose connections if the connection is intended for tank draining. You are not required to install a backflow preventer on clothes washing machine hose connections if a backflow preventer is installed inside the machine.

Backflow Protection of Boilers
1. Protect boiler fill connections by installing an approved atmospheric backflow preventer when the boiler is filled only with water.
2. Protect boiler fill connections with an air gap or an approved reduced pressure backflow preventer when the boiler water contains chemicals.

Backflow Protection of Irrigation Systems
1. Protect lawn irrigation system water connections by installing an atmospheric vacuum breaker, a pressure vacuum breaker, or a reduced pressure backflow preventer.
2. Do not install a valve downstream from an atmospheric vacuum breaker.
3. Install a reduced pressure backflow preventer if chemicals are introduced into the irrigation system.

Backflow Protection of Automatic Fire Sprinkler Systems
1. Protect automatic fire sprinkler system water connections by installing a double check-valve assembly or a reduced pressure backflow preventer.
2. You are not required to protect the fire sprinkler water connection if the fire sprinkler pipes are installed as part of the building’s potable water supply system according to IRC provisions and the sprinkler system does not have a fire department connection. This exception applies only when the fire sprinkler system and potable water supply system share some or all pipes and no fire department connection point is provided. If the fire sprinkler system and potable water supply system share only a connection to the main water service, then backflow protection is required.
3. Protect sections of the fire sprinkler system that contain chemicals or antifreeze or are connected to a non-potable water source by installing a reduced pressure backflow preventer. Protect the entire fire sprinkler system if the entire system contains chemicals, antifreeze, or non-potable water.