Backflow is the undesirable reversal in the flow of water from a real or potential source of contamination back to the potable (or clean) water supply. Imagine having a garden hose in a bucket of soapy water at your home, and having a backflow event occur causing that soapy water to "backflow" into the drinking water portion of your home.
The most common types are reduced pressure backflow preventer and double backflow preventer valves. All Family Plumbing will determine which style of backflow device is correct for your application and install the protection and safety your family deserves.