Fire Safety Science Digital Archive

Water mist fire suppression system is an attractive candidate as the Halon replacement, and much research has been made on the interaction of water mists with fires. In this paper, the interaction was studied in the confined space with proper ventilation control. The 3D LDV/APV system was employed to measure the water mist characteristics. The Cone Colorimeter was also used to measure the heat release rate, oxygen and carbon monoxide concentrations and other important parameters of the interaction in different conditions. The water mists suppressed fires in the confined space through oxygen displacement, evaporation cooling and heat radiation attenuation, and oxygen displacement played the very important role. The poorer ventilation, the easier suppression. The water mists took less effect on the smouldering than the flaming fires, and more smoke was produced. However the mists prevented the smouldering from bursting into flaming fires.