Pressure that resists the flow of fluid in a piping system.

A negative pressure that causes backflow.

Backflow is the flow of water or other liquids, mixtures, or substances into the distributing pipes of a potable supply of water from any sources other than its intended source.

A device to prevent water from travelling from one system back into any part of the main distribution system, usually by siphoning, especially into a potable water supply. This is generally required for sprinkler systems, handheld showers, pullout nozzle, kitchen sprayers, etc.

The overflow of a plumbing fixture due to drain stoppage e.g. a clogged toilet or a blocked.

The fill valve that controls the flow of water from the water supply line into a gravity-operated toilet tank. It is controlled by a float mechanism that floats in the tank water. When the toilet is flushed, the float drops and opens the ballcock, releasing water into the tank and/or bowl. As the water in the tank is restored, the float rises and shuts off the ballcock when the tank is full.

A wrench with a long handle with jaws mounted on a swivel that allows the jaws to reach and handle nuts to fasten faucets to a previously installed sink.

A personal hygiene plumbing fixture similar in appearance to a toilet bowl used for washing genitals and posterior areas of the body. It is mounted on the floor next to a toilet and consists of a washing basin, a hot and cold faucet, and sprayer.

To drain a pipe, tube, or hose of excess air by opening a valve at the end or systematically removing the air by force or suction.

A unit of heat energy required to raise the temperature of 1 lb. of water 1 degree Fahrenheit.