The Principle Operation of a Laboratory Faucet Dual Check Vacuum Breaker – Backflow Prevention Device – General Specifications

The laboratory faucet dual check backflow prevention device (LFDC) is a backflow prevention device designed to protect the potable water supply from non-potable water that may enter the potable water system by backflow due to backsiphonage. The LFDC consist of two independently acting spring loaded check valves, force loaded or biased to a normally closed position. An atmospheric vent force loaded normally to an open position is located between the check valves. The LFDC is designed to provide protection against backsiphonage wherever a hose is connected to a faucet. The LFDC can be used for high hazard cross-connection for backsiphonage only and should not be used if there is a constant pressure condition. The LFDC is not designed to be spill proof under all service conditions. The LFDC is equipped with a means for automatically venting to atmosphere and on occasion water will temporary discharge from the atmospheric vent due to fluctuating pressure conditions in the inlet piping. The approved LFDC comes in 3/8-inch pipe thread. The inlet is typically a mail fitting and the outlet is typically a female fitting designed to accept a lab faucet hose connection. Regular checking and cleaning of the LFDC internal components assures maximum life and proper product function. Consult manufactures specifications for further information regarding maintenance and repair. The LFDC shall comply with ASSE Standard 1035.