Fire Extinguishing Efficiency of Compressed Air Foam, Water and Gel Forming Agents in a Standard Class A Test Fire

Abstract

ABSTRACT Aim: The purpose of this article is to evaluate the extinguishing efficiency of water, compressed air foam and gel forming agents in solid materials fires. Project and methods: Comparison of the efficiency of extinguishing water, gel forming agents and compressed air foam was performed by conducting an experimental study to determine the appropriate indicator. An experimental device of the compressed air foam system was used for the study. The model fire of class 1A was selected as the fire. Comparison of extinguishing compounds was evaluated by extinguishing efficiency indicator Ie.e. There were two experiments, with three series in each. Results: Extinguishing efficiency indicator Ie.e took into account the time, and the mass of extinguishing agents needed to extinguish the model fire. Therefore, it was established that the mass of the compressed air foam used for extinguishing is 6.1 kg, which is 47% less than the mass of water used for extinguishing the test fire. With respect to the gel forming agent, the mass required for quenching was equal to 6.53 kg. This is 45% less than the weight of water and 2% less than the mass of compressed air foam. With respect to the quenching time, the greatest amount of time was observed for water. Time required for extinguishing (τ) amounted to 99 seconds. This value is 39% greater than the time it took to quench the flames using gel forming compounds, which was equal to 60 seconds. The minimum time required to extinguish the model fire (τ) was observed for compressed air foam, and was found to be 55 seconds. This is 45% less than that for water and 10% less than the time recorded for gel forming agent. Therefore, it was found that the fire extinguishing efficiency of compressed air foam is more than 80% higher than the water’s, and 15% higher in relation to gel forming agents. Conclusions: The authors analysed fire extinguishing agents that can be used to extinguish solid combustible substances. Experimental studies with standard model A fires let them to determine a quenching efficiency indicator Ie.e. Compressed air foam was found to have the highest fire extinguishing efficiency compared to water and gel forming agents. The advantages of compressed foam are due to the technology of its formation. Such foam has a high cooling and insulating ability, which is well reflected in its fire extinguishing efficiency compared to other extinguishing agents.