Plumbing and Water Systems Terminology

Front

Backsiphonage

Back

A reverse flow of water or other liquids, gases, or substances into the distribution pipes of a potable water supply from any source other than its intended source.

Front

Backpressure

Back

A condition where the pressure in a system exceeds the supply pressure, which can cause backflow.

Front

Test Cock

Back

A valve used for testing the pressure or flow of a liquid in a system.

Front

Shut off valve

Back

A valve designed to stop the flow of liquid in a pipe.

Front

Check valve

Back

A valve that allows flow in one direction and automatically prevents backflow.

Front

Gauge

Back

An instrument for measuring and indicating a quantity such as pressure, temperature, or volume.

Front

Cross Connection

Back

Any actual or potential connection between a potable water system and any source of contamination or pollution.

Front

Air Gap

Back

The unobstructed vertical space between the water outlet and the flood level of a fixture, providing backflow prevention.

Front

Pressure (PSI)

Back

The force exerted by a fluid per unit area, measured in pounds per square inch (PSI).

Front

Backflow

Back

The undesirable reversal of flow of water or mixtures of water and other undesirable substances into the distribution pipes of the potable water supply.