Egon Harig GmbH - Aerosol extinguishing agent

Aerosol as an extinguishing agent

Aerosol as an extinguishing agent, often referred to as dry mist, is a potassium carbonate-based particle extinguisher, which separates the chemical bond of the flame at the molecular level.

What is an aerosol?

An aerosol is a heterogeneous mixture of a gas and fine liquid or solid colloidal suspended particles.

Definition of colloids: particles with a diameter of a few micro- to nanometers, finely dispersed in a solid, gas or liquid

NO foam NO water NO gas NO powder

Structure of an extinguishing generator

Aerosol as extinguishing agent in solid form is the main component in cylindrical or box-shaped extinguishing generators.

In the event of fire, this is ignited by an electrical or thermal impulse. The reaction process produces potassium carbonate (also used as an additive E501 in food), which exits as a solid aerosol (the average particle size of the extinguishing agent is between 0.5 and 2.5 μm).

When the extinguishing agent exits the aerosol extinguishing generators, the chemical chain reaction of the flame is interrupted, and the fire is extinguished within seconds.

Electrical connection

Electric trigger

Aerosol as solid compound

Cooling zone

Discharge port

How does aerosol extinguishing agent extinguish?

Fire fighting at the molecular level

While conventional extinguishing agents rely on cooling (1) or oxygen removal (2) during the extinguishing process, aerosol as an extinguishing agent uses the molecular level (4) to break up the resulting flame within seconds and thus extinguish it.

This chemical reaction prevents re-ignition as long as the aerosol extinguishing agent is present in the room.

1 = heat (ignition energy) e.g. ext. water
2 = oxygen (oxidizing agent) e.g. CO2
3 = fuel
4 = uninhibited chemical chain reaction Aerosol extinguishing agent

Extinguishing process


	An aerosol is a mixture of a gas and very fine liquid or solid particles. When an aerosol generator is triggered, the aerosol based on potassium carbonate is generated and released.
		Chemical process: When the aerosol hits the flame, the binding of free radicals interrupts the chain reaction of the combustion process. The flame extinguishes.
For a chemical reaction to take place the activation energy is needed. The required amount of energy is provided by the excess energy from the fire.
	The flame extinguishes in seconds. As long as the aerosol is still present in the room re ignition is impossible.