What types of fire extinguisher are there?

When you’re specifying fire extinguishers, it’s important you get the correct type for the area it will cover, as the wrong type won’t be as effective if a fire breaks out.
Your choice should be based on the things which might catch fire in the location. The British Standard breaks these down into six fire classifications.

Fire Classifications

• Class A fires – involve freely burning organic solid materials like paper, wood, textiles and other carbonaceous materials.
• Class B fires – are of flammable liquids such as petrol and spirits, but not alcohol or cooking oil.
• Class C fires – involve flammable gases such as propane and butane.
• Class D fires – are fires involving burning metals such as magnesium or lithium (think rechargeable battery packs).
• Class F fires – involve fats, such as cooking oil, lard or butter.
• Electrical fires – are fires caused by faults in electrical equipment, though these can fall into any of the classifications as it’s the stuff near the electric source which is burning, not the power itself.

Types of extinguisher

There are seven types of extinguisher in use, based on the content they expel to fight the fire: Water – these are the classic Signal Red extinguisher seen most often and should only be used on Class A fires.

• Water Mist - these are white and red and can be used on Classes A, F, B and C, as well as electrical fires if they’ve been dielectrically tested and are dispensing deionised water.
• Foam – these are suitable for Classes A and B fires, plus electrical ones if the contents have been dielectrically tested.
• Dry Powder - suitable for Classes A, B and C, plus electrical fires.
• Carbon Dioxide - suitable for Class B and electrical only.
• Wet Chemical - suitable for Classes A and F, as well as some Class B fires.
• Specialist Powder – these should only be used on Class D fires.

Fire rating

All extinguishers suitable for Class A, B or F fires carry a fire rating shown by a number and letter e.g. 13A. The number shows the size of fire it was found to extinguish well under test conditions. The larger the number, the larger the fire it can extinguish.
The letter indicates the fire classification. Classes C, D and extinguishers for electrical fire don’t have a number rating for those types of fire.

Choosing the right type of extinguisher

Commercial and public organisations are required to have a survey conducted by a qualified person to find the number and type of extinguishers required for each location.
For the kitchen in your home, a fire blanket and a small wet chemical extinguisher or water mist extinguisher using deionised water is usually considered enough for most situations. A water mist extinguisher is suitable for the rest of the house because of its broad capability across most fire types.
If you’re unsure about what type of extinguisher you need where, particularly in areas with multiple risk types, get in touch so we can arrange to conduct a survey and advise on the best type/s for each location.

Get in touch

Fraser Fire & Security provides fire safety and security services across Aberdeen, Aberdeenshire, Moray and Inverness. For more information get in touch.

We are committed to keeping people and assets safe through a professional and customer-focussed service.
Our team of five fully-qualified and highly experienced experts provide fire safety and security services across Aberdeen, Aberdeenshire, Moray and Inverness, taking a proactive approach to legislation to ensure 24/7 compliance.

Commercial services include: Fire Safety Services, Risk Assessments & Fire Training, Fire Alarm Supply, Installation & Maintenance; Intruder Alarm Design, Installation & Maintenance; Fire Extinguisher Installation & Servicing; CCTV Design and Installation.
We specialise in CCTV Systems for farms, including packages to support landlords and property owners for Smoke Detection and Security.

Our commercial clients include Baxters, Walkers, Brewdog and Excel Scotland.