The following are some definitions to keep in mind when talking about backflow, its prevention and equipment:

Air Gap Separation

A physical space that is present between two objects


To reverse the natural and normal flow of a liquid, gas or solid substance back into the public potable (drinking) water supply

Backflow Prevention

To stop or prevent the occurrence of the unnatural act of reversing the normal direction of the flow of liquids, gases, or solid substances back into the public potable (drinking) water


A liquid substance that is carried over a higher point. It is the method by which the liquid substance may be forced by excess pressure over or into a higher point


To make something bad. To pollute or infect something. To reduce the quality of the potable (drinking) water and create an actual hazard to the water supply by poisoning or through spread of diseases


To decay or rot

Flood Rim

The point of an object where the water would run over the edge of something and begin to cause a flood


Water this is furnished to help provide and sustain the life of growing plants. It comes from ditches, lakes, streams, and ground water. It is sometimes treated with herbicides and pesticides to prevent the growth of weeds and the development of bugs on plant life


To make something unclean or impure; contaiminated


Good water which is safe for drinking. Non-Potable: A liquid or water that is not intended for drinking


To take action to stop something before it happens


To cover with water or liquid substance


If water flows through a pipeline at a high velocity, the pressure in the pipeline is reduced. Velocities can be increased to a point that a partial vacuum is created

Water Purveyor

The individual(s) responsible to help provide, supply and furnish quality water to a community