What Are the Different Types of Fire Extinguisher and When Should They Be Used?

As a business owner, you know that you have a duty of care for your employees and customers. Part of that is ensuring that you have the right safety equipment in place. But with fire extinguishers, it can feel like a bit of a minefield. There are so many different variables to consider that it can never be a case of ‘one size fits all’. So, what do you need to know before selecting the right types of fire extinguisher for your business?

The Six Different Classes of Fire

Classes of fire and fire extinguishers

Before you can decide on the right type of fire extinguisher(s) for your business, you first need to understand the ways in which fire is classified. This should help you to better calculate the fire risks for your business.

Class A – Solids –This could be wood, plastic, paper, fabrics, soft furnishings, fixtures, or fittings.

Class B – Flammable liquids – There is a whole range of items that fit within this category, including solvents, paints, cleaning fluids, and fuels.

Class C – Gases – Flammable gasses include butane, propane, methane, LPG.

Class D – Metals – Although you might not consider metal as a fire risk, some are surprisingly combustible (sodium, for instance). Most metals also make very good conductors.

Electrical – Because electrical fires can easily fall within many of the other classes, they don’t really get their own full class. But electrical fires usually refer to wiring and equipment such as computers, televisions, and routers.

Class F – Cooking fats and oils – This is fairly self-explanatory and relates to things like chip pan fires.

So, now you know what types of fire to prepare for. But which fire extinguisher do you use to tackle them? Find out about each of the main types of fire extinguisher below.

The five main types of fire extinguisher and their uses

Types of Fire Extinguisher Powder

Powder extinguishers

Used for: Class A, B, C and D fires, plus electronic equipment of less than 1,000v
Label colour: Blue

Powder fire extinguishers are comprised of dry powder and nitrogen. And they are among the most versatile extinguishers around in terms of the fires they can tackle. They work by smothering the fire with powder, which forms a crust, preventing oxygen from fuelling the flames and stopping the fire from spreading. This does not reduce the heat of the fire, however, which can lead to reignition.

Are there any limitations with powder extinguishers?

Although powder fire extinguishers are versatile, they should never be used in an enclosed space, which limits their usefulness. This is because the powder can impair breathing and impact visibility. They are also extremely messy and can be very difficult to clean up after use. Which is another good reason not to use them indoors!

Where would you use a powder fire extinguisher?

Powder fire extinguishers are ideal for outdoor locations, such as garage forecourts or welding workshops.

Powder extinguishers

Used for: Class A, B, C and D fires, plus electronic equipment of less than 1,000v
Label colour: Blue

Powder fire extinguishers are comprised of dry powder and nitrogen. And they are among the most versatile extinguishers around in terms of the fires they can tackle. They work by smothering the fire with powder, which forms a crust, preventing oxygen from fuelling the flames and stopping the fire from spreading. This does not reduce the heat of the fire, however, which can lead to reignition.

Are there any limitations with powder extinguishers?

Although powder fire extinguishers are versatile, they should never be used in an enclosed space, which limits their usefulness. This is because the powder can impair breathing and impact visibility. They are also extremely messy and can be very difficult to clean up after use. Which is another good reason not to use them indoors!

Where would you use a powder fire extinguisher?

Powder fire extinguishers are ideal for outdoor locations, such as garage forecourts or welding workshops.

Types of Fire Extinguisher Powder
Types of Fire Extinguisher Foam

Foam extinguishers

Used for: Class A and B fires
Label colour: Cream

Like the dry powder fire extinguisher, foam extinguishers work by smothering the fire to prevent it from spreading, sealing in the flammable vapours. But it also has the added benefit of cooling the fire, which helps to prevent it from reigniting. When used on a liquid fire, the foam also forms a barrier between the liquid’s surface and the flames, preventing spread.

Are there any limitations with foam extinguishers?

The main issue associated with foam fire extinguishers is that they leave a residue after use, which can be difficult to clean. They are also not suitable for use with free-flowing liquid fires.

Where would you use a foam fire extinguisher?

Foam fire extinguishers are light, effective, and useful for the most common fire types, making them a great choice for schools, offices, hotels, shops, hospitals, warehouses, and homes.

Foam extinguishers

Used for: Class A and B fires
Label colour: Cream

Like the dry powder fire extinguisher, foam extinguishers work by smothering the fire to prevent it from spreading, sealing in the flammable vapours. But it also has the added benefit of cooling the fire, which helps to prevent it from reigniting. When used on a liquid fire, the foam also forms a barrier between the liquid’s surface and the flames, preventing spread.

Are there any limitations with foam extinguishers?

The main issue associated with foam fire extinguishers is that they leave a residue after use, which can be difficult to clean. They are also not suitable for use with free-flowing liquid fires.

Where would you use a foam fire extinguisher?

Foam fire extinguishers are light, effective, and useful for the most common fire types, making them a great choice for schools, offices, hotels, shops, hospitals, warehouses, and homes.

Types of Fire Extinguisher Foam
Types of Fire Extinguisher CO2

Carbon dioxide extinguishers

Used for: Electrical and Class B fires
Label colour: Black

Carbon dioxide fire extinguishers work by displacing oxygen, effectively suppressing electrical fires. They are also cooling, which can help prevent the fire from reigniting. Because they are residue-free, these extinguishers avoid causing any additional damage and remove the need for extensive cleaning.

Are there any limitations with carbon dioxide extinguishers?

Carbon dioxide extinguishers come with a couple of significant problems that users must be aware of. The most important being that if used in enclosed spaces, they can cause asphyxiation. Depending on the build, the extinguishers can also become extremely cold when being discharged which runs the risk of the user’s hands becoming frozen to the extinguisher– it always pays to invest in double-lined, frost-free models.

Where would you use a carbon dioxide fire extinguisher?

Carbon dioxide extinguishers are particularly useful in places where you have a high density of electrical equipment, such as server rooms and offices.

Carbon dioxide extinguishers

Used for: Electrical and Class B fires
Label colour: Black

Carbon dioxide fire extinguishers work by displacing oxygen, effectively suppressing electrical fires. They are also cooling, which can help prevent the fire from reigniting. Because they are residue-free, these extinguishers avoid causing any additional damage and remove the need for extensive cleaning.

Are there any limitations with carbon dioxide extinguishers?

Carbon dioxide extinguishers come with a couple of significant problems that users must be aware of. The most important being that if used in enclosed spaces, they can cause asphyxiation. Depending on the build, the extinguishers can also become extremely cold when being discharged which runs the risk of the user’s hands becoming frozen to the extinguisher– it always pays to invest in double-lined, frost-free models.

Where would you use a carbon dioxide fire extinguisher?

Carbon dioxide extinguishers are particularly useful in places where you have a high density of electrical equipment, such as server rooms and offices.

Types of Fire Extinguisher CO2
Types of Fire Extinguisher Water

Water extinguishers

Used for: Class A fires
Label colour: Red

Water fire extinguishers come in two forms – pressurised and mist. They’re probably the most commonly used extinguisher around, largely because they are the simplest and the cheapest. And they work as you’d expect – by soaking the fire with water, reducing heat, and quenching flames.

Are there any limitations with water extinguishers?

The only real drawback of the water extinguisher is that it can only be used on class A fires and is dangerously incompatible with gas, liquid, fat and electrical fires.

Where would you use a water fire extinguisher?

Most professional premises will have at least one water extinguisher: hospitals, shops, apartment blocks, schools, factories.

Water extinguishers

Used for: Class A fires
Label colour: Red

Water fire extinguishers come in two forms – pressurised and mist. They’re probably the most commonly used extinguisher around, largely because they are the simplest and the cheapest. And they work as you’d expect – by soaking the fire with water, reducing heat, and quenching flames.

Are there any limitations with water extinguishers?

The only real drawback of the water extinguisher is that it can only be used on class A fires and is dangerously incompatible with gas, liquid, fat and electrical fires.

Where would you use a water fire extinguisher?

Most professional premises will have at least one water extinguisher: hospitals, shops, apartment blocks, schools, factories.

Types of Fire Extinguisher Water
Types of Fire Extinguisher Chemical

Wet chemical extinguishers

Used for: Class F fires
Label colour: Yellow

Created specifically for the tackling of kitchen and oil fires, wet chemical extinguishers use a potassium solution to cool the fire while preventing the oil from splashing and causing further damage or injury.

Are there any limitations with wet chemical extinguishers?

Again, as long as they are used in the right circumstances, there are no real negatives to the wet chemical fire extinguisher.

Where would you use a wet fire extinguisher?

Wet fire extinguishers are designed for anywhere that cooking takes place – school canteens, restaurants, cafes, and commercial kitchens.

Wet chemical extinguishers

Used for: Class F fires
Label colour: Yellow

Created specifically for the tackling of kitchen and oil fires, wet chemical extinguishers use a potassium solution to cool the fire while preventing the oil from splashing and causing further damage or injury.

Are there any limitations with wet chemical extinguishers?

Again, as long as they are used in the right circumstances, there are no real negatives to the wet chemical fire extinguisher.

Where would you use a wet fire extinguisher?

Wet fire extinguishers are designed for anywhere that cooking takes place – school canteens, restaurants, cafes, and commercial kitchens.

Types of Fire Extinguisher Chemical

Fire extinguisher commissioning

Fire Extinguisher Servicing Specialist

Once you’ve selected fire extinguishers for your business, you are legally obliged to have them commissioned – checked for compliance with UK fire extinguisher legislation. This is a precaution to ensure that the extinguishers are safe, properly installed, and correctly assembled. To keep your business compliant with British Standard 5306 Part 3 2009 recommends the annual inspection of fire extinguishers. Our experts who are all fully qualified and certified with BAFE at 1st Class Fire Protection can assist your business with this to keep you compliant.

Choosing the right fire extinguishers for the right places within your business can literally be a lifesaver. If you’re unsure or would like tailored advice about finding the right equipment for your business or organisation, then get in touch with 1st Class Fire Protection today either on 01603 742741 or request a call back with our expert team.