You are in [ AQUASYS -> Tunnel Systems -> Technical Description]

General System Description

  • The AQUASYS Water Mist Fire Fighting System is designed for fire loads in tunnels up to 125,000 MJ or 200kW. It has been tested in numerous full-scale trials in a real tunnel and the performance is certified by the independent laboratories VdS Germany and IBS Austria.
  • The AQUASYS Water Mist Fire Fighting System basically consists of the spray nozzles and pipe network, the main pumps and the control system.
  • The pump station containing the main pumps shall be located at the middle of the tunnel or at one of the tunnel portals. It usually contains three main pumps, two for normal operation and one backup unit in case of malfunction. The main pumps are driven by electric motors or diesel engine.
  • The spray nozzles inside the tunnel are mounted in line wih the nozzle tubes. For protection the nozzles from impurities, in line filters in the pressure line are used. They are located at the main pumps.
  • The main lines between the high pressure supply unit and the diverter valves are always filled with water and pressurised.
  • The distribution and nozzle lines downstream from the diverter valves are normally dry and only will be pressurised during fire fighting.
  • Upon detection of fire, the control unit starts the high pressure unit and opens the diverter valve of the section where the fire was detected, together with the two diverter valves of the adjacent sections. The production of water mist will be started within a few seconds.
  • Depending on the size of the water reservoir, the water mist production can be maintained until fire fighting forces reach the scene.