Electrical fire classes explained
How electrical fires are classified in Australia, and what it means for choosing an extinguisher
"What class is an electrical fire?" is one of the most-asked questions in fire safety, and it trips people up because the answer is different in Australia than in some overseas guides. Get the class right and the extinguisher choice follows naturally. Get it wrong and you risk grabbing the wrong unit when it matters most.
Here is how the classes work in Australia, and where electrical fires sit.
At Industro, we supply fire extinguishers and fire safety equipment to warehouses, workshops, factories, commercial buildings and government sites across Australia. our fire extinguisher range
Why fires are classified at all
A fire class simply groups fires by what is burning, because different fuels behave differently and need different extinguishing agents. Paper does not burn like petrol, petrol does not burn like cooking oil, and none of them behave like energised electrical equipment. Matching the extinguisher to the class is what keeps a small fire from becoming a big one.
The Australian fire classes
| Class | Fuel | Typical examples |
|---|---|---|
| A | Ordinary combustibles | Paper, cardboard, timber, textiles, plastics |
| B | Flammable liquids | Petrol, diesel, solvents, paints, fuels |
| C | Flammable gases | LPG, acetylene, natural gas, propane |
| D | Combustible metals | Magnesium, sodium, aluminium powders, titanium |
| E | Energised electrical equipment | Switchboards, control panels, machinery, servers, appliances |
| F | Cooking oils and fats | Deep-fryer oils, vegetable and animal fats |
The one to note: in Australia, electrical is Class E, not Class C. Class C here means flammable gases. Some overseas material uses "Class C" for electrical, which is where the confusion comes from.
What makes a fire a Class E fire
A fire is Class E for as long as energised electrical equipment is involved, switchboards, distribution boards, motors, servers, chargers, appliances and the like. The moment the power is isolated and the equipment is no longer live, the fire is reclassified by whatever is actually burning (often Class A materials around it), and treated accordingly.
That is why isolating power is the first move wherever it is safe to do so.
Which extinguishers suit Class E
The two used most in Australian workplaces are CO2 (no residue, ideal around sensitive electronics) and ABE dry chemical (rated A, B and E, the versatile all-rounder). For the full comparison and where each is used, see What Fire Extinguisher for Electrical Fires.
A note worth making: lithium battery fires are a separate problem again, and standard extinguishers do not reliably control them. See Lithium Battery Fire Extinguishers.
Where to from here
- The practical guide: What Fire Extinguisher for Electrical Fires.
- By environment: Switchboard, Server Room, Data Centre fire extinguishers.
- Outfitting a workplace: Electrical Fire Safety in the Workplace.
Need help matching extinguishers to your site's risks? The team at Industro can help. get in touch