Laboratory and Bench Methodology to Test Fire Suppressant Effectiveness in Aviation Method of Extinguishing of Forest Fires

Laboratory and bench tests for evaluation of fire retaining and fire extinguishing properties of agents used for fighting forest fires are described. The methodology gives not only a possibility to understand the effectiveness of the agents themselves but also to determine the characteristics of their discharge from an aircraft, in particular, the length and width of the wetted strip, the irrigation density and the flight altitude. Laboratory experiments confirm high fire retaining efficiency of aqueous solutions of magnesium halides and diammonium phosphate which cause significant delay in ignition time and substantial increase in ignition temperature for wood treated with these solutions. The efficiency of the halides significantly increases in the row MgCl2 < MgBr2 < MgI2. It was also shown by the experiments that the irrigation density by aqueous solutions necessary to extinguish grassroots and crown forest fires decreases when using Firex wetting agent and increases for bischofite and bentonite.