Safe Suction [1]

A term used to describe a suction pumping system where the following are true:

1) There is only one check valve located immediately below the pump.
2) The pump is at a higher elevation than the tank
3) The piping slopes continually back to the tank.

Suction pumping systems incorporating these features are “safe” because leaks in the piping will result in a loss of prime [2] but not release of product outside the primary containment [3].