Back-siphonage backflow definition
Back-siphonage backflow means a reversal of the normal direction of flow in the pipeline due to a negative pressure (vacuum) being created in the supply line with the backflow source subject to atmospheric pressure.
Back-siphonage backflow means the flowing back of used, contaminated, or polluted fluid from a plumbing fixture or vessel into a water supply pipe due to a pressure less than atmospheric in such pipe.