15. ožujak 2021.

Classes of fires by type of combustible substances and their extinguishing by fire extinguishers.

Fire Extinguishers are the most widespread firefighting equipment and are one of the first choice when equipping residential and business premises with firefighting equipment. They are filled with a variety of extinguishing agents and allow us to react quickly in the case of a fire.

Fire extinguishers have labels that contain instructions for their activation and also indicate which types of fires can be extinguished with this extinguisher. According to the type of substance, fires are classified into five classes (standards):

CLASS A

Fires of solid flammable substances (wood, paper, straw, textiles, coal). We usually put out such fires with water.

CLASS B

Flammable liquid fires (petrol, oil, grease, varnishes, wax). We extinguish such fires with foam, powder or carbon dioxide.

CLASS C

Flammable gas fires (methane, propane, butane, acetylene, etc.). These types of fires are extinguished with powder and carbon dioxide.

CLASS D

Flammable metal fires (aluminum, magnesium, their alloys, etc.). Only dry agents (special types of powder, dry quartz sand…) are used to extinguish this type of fire.

CLASS F

Cooking fats and oils (fires of vegetable and animal oils and fats). Never extinguish burning oil with water as you could cause a greasy explosion that will injure you and cause a fire in kitchen elements. The quickest way to turn off burning oil is to cover the oil pan with a lid, a damp cotton cloth or fire blanket. After extinguishing, the container should remain covered for a few minutes, as overheated oil can ignite again in contact with air.

The above fire class designations are indicated in the same form on the fire extinguisher label, which means that the extinguishing agent inside the fire extinguisher is suitable for extinguishing fires of that class. Eg. the mark on the fire extinguisher ABC means that the agent in this extinguisher is suitable for extinguishing fires of flammable solids - class A , liquids - class B and gases - Class C .

There are 2 versions of Fire Extinguishers filled with ABC powder (under constant pressure or with a bottle) - we explained the difference between these two Fire Extinguishers in the article "The difference between Fire Extinguishers". Also we have Fire Extinguishers filled with carbon dioxide, water and foam. Fire extinguishers with water and foam are equal in performance to those with powder and are easy to maintain and more environmentally friendly.