A vacuum breaker valve is a backflow preventer designed to keep your plumbing system running smoothly and, quite frankly, flowing in the direction it was designed to flow. Vacuum breaker valves are also known as check valves or vacuum breakers, and they protect the potable water supply by ensuring that water flows in the correct

An atmospheric vacuum breaker is one of many backflow devices, or backflow preventers, which prevent contaminated water from flowing back into the potable water supply. The atmospheric vacuum breaker is usually constructed of brass and it appears to be a 90-degree elbow construction with a hood on its top to allow air to enter the

  For additional protection against possible backflow into your basement, you could also add a floor drain backflow preventer.  Usually these are check valves which are inexpensive and easy to install.  What they are, basically, is a compressed rubber gasket with a floating ball mounted on a spring.  It is installed into the vertical pipe