A special system that is pipe-connected to a source of foam concentrate and to a water supply. The system is equipped with appropriate discharge devices for extinguishing agent discharge and for distribution over the area to be protected. The piping system is connected to the water supply through a control valve that usually is actuated by the operation of automatic detection. When the valve opens, water flows into the piping system, foam concentrate is injected into the water and discharges through the appropriate devices.
Commonly used in airplane hangars, fuel storage and storage areas for flammable combustible liquids