What Are The Six Classes Of Fire?
The fuel that is burning dictates the type of extinguisher you use to fight the fire. To help you understand this idea, you need to know how fires are classified and which fire extinguishers are fitting for each class.
The six classes of fire in New Zealand are
- Class A – Combustible solids
- Class B – Flammable liquids
- Class C – Flammable gases
- Class D – Combustible metals
- Class E – Electrical appliances
- Class F – Cooking fats and oils
In this article, we will cover the different classes of fire in detail and provide you with the knowledge of which fire extinguisher is best to use.
Class A Fires
Class A fires involve combustible solid materials that can be found in businesses and homes. The most common materials include paper, textile materials, plastics, rubber and wood.
An example of a class A fire could be the ignition of rubbish bins or furniture due to hot embers.
The type of fire extinguishers that are recommended for A-class fires are
- Water fire extinguisher
- Dry Powder ABE fire extinguisher
- Wet chemical fire extinguisher
- Foam fire extinguisher
Class B Fires
Class B fires are fires that are caused by flammable and combustible liquids such as chemical-based petrol, kerosene, alcohol, oil, paint thinners and plastic.
It’s typical for a class B fire to occur within a workshop environment such as a panel beater or mechanics, some typical cases of ignition include welding or sparks from power tools that come into contact with flammable oils.
The recommended type of fire extinguishers to fight class B fires are
- Foam fire extinguisher
- Dry Powder ABE fire extinguisher
- CO2 fire extinguisher
It is crucial to remember that you never use water on an oil-based fire as it has the potential to spread the fire and will more than likely cause an explosion of the burning oil.
Class C Fires
Class C fires are caused by flammable gases such as LPG, methane, acetylene, hydrogen, natural gas and butane. These gases are often found within workshops, garages and kitchens.
It is common for class C fires to happen due to gas leaks from cooktops, stoves, gas-powered tools or the workshop barbecue.
The only type of fire extinguisher recommended for class C fires is
- ABE Dry Powder fire extinguisher
Class D Fires
Class D fires happen due to combustible metals such as potassium, sodium, lithium, aluminium, magnesium and swarf. These types of fires are not as common because metal requires a significant amount of heat to ignite.
There are specialised dry powders to control this class of fire. You can also use sand to smother the fire.
Class E Fires
Class E fires involve energised electrical equipment such as fan heaters, electronics and kitchen appliances. These are a common cause of fire within the home or workplace.
A typical example of a class E fire is from electrical appliances overheating, faulty tools, heaters being covered and frayed wiring.
The recommended type of fire extinguisher for a Class E fire are
- Dry Powder ABE fire extinguisher
- CO2 fire extinguisher
Class F Fires
Class F Fires are caused by cooking fats and oils. This type of fire is more likely to occur within food preparation areas and kitchens.
A common scenario for a class F fire would be when a pan of hot oil overheats or oil spitting when cooking.
The recommended type of extinguishers for class F fires are
- Fire blanket
- Wet chemical fire extinguisher