A Back Pressure is a pressure that can cause water to Backflow into the water supply when a user's waste water system is at a higher pressure than the public system.

A Backflow /Back Siphonage is a reverse flow condition created by a difference in water pressures that causes water to flow back into the distribution pipes of a drinking water supply

Backflow is a reverse flow in water pipes.

- Background: A background (radiation) is Natural radiation caused by sun exposure, cosmic rays from space, and radioactive elements found in the earth's crust.

A Background concentrations: is In this context, EPA uses background concentrations to mean the contributions to outdoor Air Toxics concentrations resulting from natural sources, persistence in the environment of past years' emissions and long-range transport from distant sources.

A Background count rate is the counting rate obtained on a given instrument with a background counting sample. Typical reference background counting samples are:

Background extinction is the normal extinction of various species as a result of changes in local Environmental conditions. Compare mass depletion, mass extinction.

A Background Level is
1. The Concentration of a substance in an Environmental media (air, water, or soil) that occurs naturally or is not the result of human activities.
2. In Read more ... Add new comment