Fire extinguishing principle of dry powder fire extinguishers
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This post was last edited by fight3558586 on 2016-12-24 09:44. There are four methods of extinguishing fires: cooling, smothering, isolation, and suppression. What is the principle of fire extinguishment for dry powder fire extinguishers?
Suffocation is achieved by covering the fire source with a large amount of dry powder to isolate it from air.
The powder falls on the surface of combustible materials, where it undergoes a chemical reaction; under high temperatures, this forms a glass-like coating that prevents oxygen from reaching the material, thereby extinguishing the fire through suffocation. In addition, it also helps to dilute the oxygen and has a cooling effect.
1. Through the volatile decomposition products of inorganic salts in the dry powder, chemical inhibition and synergistic catalytic effects occur with the free radicals or reactive groups generated by the fuel during combustion, thereby interrupting the chain reaction of combustion and extinguishing the fire； 2. The dry powder falls onto the surface of the combustible material, where it undergoes a chemical reaction; under high temperatures, this forms a glass-like coating that prevents oxygen from reaching the material, thereby extinguishing the fire through suffocation.
Mixed type: isolation, suffocation, cooling