Fire extinguisher

There are four classes of fires. Before you extinguish a fire, you need to make sure you identify the type of fire; otherwise, you might make things worse.

Classes of fires:

  • class A ordinary combustibles or fibrous material: wood, paper, plastic;

  • class B flammable or combustible liquids: paint, kerosene;

  • class C energized electrical equipment: switches, panel boxes;

  • class D combustible metals: magnesium, potassium.

Most labs are equipped with dry chemical extinguishers (ABC extinguishers) that can be used for the first three classes.

CO2 extinguishers are also very popular. They can be used for class B and C fires. Don't use CO2 extinguishers on people as it can cause serious frostbites.

Further reading: