Backflow prevention device

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A backflow prevention device is used to protect water supplies from contamination or pollution. Many types of backflow prevention devices also have test ports so that they can be tested or examined to ensure that they are functioning properly. Many states and/or local municipalities actually require annual testing of such devices. A check valve is a common form of a backflow preventer.

Backflow prevention protects the potable water system from minor, moderate, and severe hazards. There are over 10,000 reported cases of backflow contamination each year. Some cases can be fatal. Backflow devices are required by law where needed and must be installed in accordance with plumbing or building codes. A backflow assembly has test cocks and shut-off valves and must be tested each year, if relocated or repaired, and when installed.

In this situation, dirty water from the hillside pool will back siphon or back flow down the hosepipe and into the clean water tank. To prevent this from happening, the house's external tap should be fitted with a backflow prevention device.

The simplest, and most effective way to provide backflow prevention is to provide an air gap. An air gap is simply a space between any device that opens to a plumbing system (like a valve or faucet) and any place where water can collect or pool.