Abstract: In this paper, a water spraying device for LNG tank vehicles is designed for fire inhibition tests when LNG leaks in the control cabinet and fire extinguishing tests when LNG is ignited. In addition, effects of different nozzle numbers, heights, intervals, outlet directions, diameters, locations on fire retardancy and extinguishing are investigated to optimize the spraying device. The results show that the optimal parameters of spraying device are: nozzle diameter Φ2.5 mm, nozzle height 1100mm, interval between two nozzles 900 mm. After opening the spraying device, the humidity value increases rapidly and stables up to 83.2% within 600 seconds. Experientially, this humidity level can effectively reduce deflagration risks. Once LNG is ignited, this device can effectively control or put out fire which can save sufficient time for following emergency disposal.

Key words: LNG, tank vehicles, leakage, emergency disposal, water spraying