The application of fire extinguishers is to extinguish initial fires, inflammable liquids, gaseous substances and electric installations under 1000V ( with the exception of water and water foam  fire extinguishers )

Fire extinguishers are used to equip all buildings, installations, vehicles, agricultural machines and buildings, etc.

All fire extinguishers consist of extinguishing substance, metal cylinder, forcing gas, valve with safety vent, manometer ( for fire extinguishers type H ), nozzle and hose for control of the stream, approved label complying with Bulgarian National Standard EN 3, lead seal and accessories.

Fires:  ( more info ) 

Class A – Solid materials – wood, paper, charcoal, rubber, textile, etc

Class B – Liquid or inflammable liquids – petrol, diesel, paint, solvents, oil, benzene, ethylene, etc

Class C -  Gases – metan, propane, acetylene, natural gas, hydrogen, etc.

All fire extinguishers are subject to compulsory annual inspection whether they are used or not !!! (more info )