Discover the main fire extinguishing agents
How to interrupt a fire
To interrupt the combustion, there are four extinguishment processes:
- Temperature reduction and Heat Removal
- Fuel removal
- Oxygen removal
- Chemical Flame Inhibition
Extinguishing Agents use one (and sometime more than one) of these processes to turn off a fire.
Temperature Reduction/Heat Removal: freezing the fire.
Cooling temperature of fuel and removing the heat from the compartment, to below ignition temperature, is one of the process uses by water and extinguishing powder.
Insufficient cooling can lead to rekindling, and flammable vapors may continue to be released (If fuel temperature is above flash point, a source of ignition with sufficient energy will cause reignition)
Fuel Removal: starving the fire.
Stop flow of liquid or gaseous fuel is one of the most evident way to stop a fire.
When wildland fires occur, removing vegetation in front of the fire or backfire or burn fuel in front of main fire are the main strategy to turn off a fire.
Oxygen Depletion: suffocating the fire.
Reducing or removing the amount of oxygen available to the combustion is the best way to extinguish a fire.
In order to achieve this, flooding area with inert gas, blanketing fuel with foam or covering coal with airtight varnish can be use to accomplish this suppression.
Chemical Flame Inhibition: disturbing the fire.
Some extinguishing agents can interrupt or disrupt enough the chemistry and the mechanism of the combustion reaction. Some extinguishing powders and some gaseous agents use this strategy to disorganize an established fire.