When a fire breaks out in a small enclosed area and temperature rises, extinguishing liquid simultaneously begins to heat and as a result, the liquid starts to extend in the glass ampoule.
When the temperature of the extinguishing liquid is approximately 85°C ± 5°C the glass breaks into pieces which allows the liquid to drop into the area, where endothermic process begins.
It takes the energy from the fire and starts to cool the area.
As a side product of this endothermic reaction, small quantities of nitrogen and carbon dioxide are released.
Their function is to prevent the entrance of oxygen to the burning area.
Remaining components that do not decay, form a protective layer over the surface of the extinguishing liquid, which prevents re-ignition.