Medium velocity water spray system to protect cable gallery, machinery , conveyors, LPG bullets, NH3 storage tanks, oil storage tanks, and other similar applications. The system comprises of network of underground and above ground piping, control valve( Deluge Valve), sprinkler bulb detectors, water spray nozzles/Projectors. System is pressurized with water up to below the control valve ( deluge valve ) using pumps and connected to a reliable source of water supply. The piping network above the control valve remains empty consisting open spray nozzles/projectors