The Explainer: What do you mean there are "different classes of fire"?

There’s more to know about fire than that its hot and a big red truck will turn up and take care of it, especially if you hope to control a small fire in your home or workplace before it becomes unsafe and out of control.

In Australia, fires are identified by classes with each class (A – F) representing a different type of fire.

Each class of fire has its own characteristics, associated dangers, and requires a different technique to extinguish it.

This explainer will walk you through the key categories and how trained personnel may safely fight each class of fire.

Class A - Household/Office Fire

Class A fires are the most common type of fire firefighters respond to, and involve combustible materials such as wood, paper, or fabric. This could be a rubbish bin, couch, or clothing. Most types of extinguishers will be able to control a small class A fire, however, CO2 extinguishers are not recommended for this class.

Class B - Flammable Liquid Fires

Class B fires involve flammable or combustible liquids, such as petrol, kerosine, or oil. The most appropriate type if extinguisher to use for a class B fire is ABE Dry Powder, but foam or CO2 extinguishers will also work. It is extremely important that you do attempt to extinguish a class b fire with water .

Class C - Gas Fires

Class C fires involve combustible or flammable gasses such as CNG, LNG, propane, or butane. Most of us have seen a gas BBQ or stove top operating, this is a controlled class C fire that can be adjusted or isolated with a dial. It is not recommended that you attempt to extinguish a class C fire as this will then lead to an uncontrolled gas release and could result in an explosion, if you identify a class C fire you must first isolate the gas supply and then extinguish with an ABE Dry Powder extinguisher.

Class D - Battery Fires

Class D fires involve metals such as magnesium or lithium iron. The most common cause of class D fires is batteries of portable electronic devices. None of the common extinguishers are suitable to fight a class D fire. Class D fires produce highly toxic fumes so it is recommended that you evacuate, closing doors and windows as you leave (if safe to do so) and call 000 from a safe place.

Class E - Electrical Fires

Class E fires are when energized electrical equipment is involved in fire, such as a switchboard, multi plug, or electric blanket. It is recommended to use CO2 or ABE Dry Powder on a class E fire. Never use water on an electrical fire, and always attempt to isolate the electricity if safe to do so.

Class F - Fat Fires

Class F fires are very common in kitchen environments, as class F fires involve cooking oils or fats. Extreme caution must be taken with class F fires as they will likely be spitting boiling oil at you. Commercial kitchens may have Wet Chemical type extinguishers, however these are not overly common. To control a class F fire it is best to use a fire blanket, pot lid, or chopping board to cover the pot or pan that is on fire and starve it from oxygen. You may also use a ABE Dry Powder extinguisher but you must be cautious not to splash the burning liquid further. Never use water on a class F fire as this will cause an explosion, and result in serious injury, and rapid spread of fire.

Now that you know the basics of different classes of fire, and the different extinguishers used for each, you can use the chart below as a quick guide to which extinguishers are best suited for which class of fire.

We recommend attending a practical training session so you and your team are competent and confidence in your understanding of using various fire extinguishers. We’ve included an example of fire extinguisher training below to get you started. Reach out to our team to find out more.