To operate the extinguisher , remove the guard cap and strike the plunged against a hard surface like the floor keep the cylinder inverted.
Direct the jet emerging from the nozzle on the base of fire. When the plunger is struck , it breaks the acid phial (bottle ) .
The sulphuric acid and sodium bicarbonate solution react together to release carbon dioxide (CO2 )
The CO2 generated creates pressure which forces the water out of the extinguisher .
Note : the CO2 acts only as a propellant and water extinguishes the fire cooling effect.