In a drainage system, a piping arrangement in which a drain from an appliance, device, or fixture discharges into the open air and then into another fixture, receptacle, or interceptor; used to prevent back siphonage or backflow.
In a drainage system, a piping arrangement in which a drain from an appliance, device, or fixture discharges into the open air and then into another fixture, receptacle, or interceptor; used to prevent back siphonage or backflow.