While fire safety is, without a doubt, extremely important, it can often be confusing. Understanding what your fire safety needs are can often require no small amount of time and effort. Not only that but there are so many different types of fire extinguishers available that it can be overwhelming to figure out which is the right choice for your needs.

In this article, we will use Fire Protection Shop’s own FireShield brand of fire extinguishers to guide you through the different types of fire extinguishers available to you. We will discuss how to establish your fire safety needs, the classifications of fire, and the benefits of each fire extinguisher category.

How do fire extinguishers work?

Fire needs 3 things to sustain itself: a source of ignition, a fuel source, and oxygen. This is known as the “Fire Triangle.” Fire extinguishers work by removing one or more components of the fire triangle.

The simplest elements to remove are heat and oxygen. A water jet fire extinguisher, for example, works by using the cooling effect of the water to remove the heat from the triangle, whereas a CO2 extinguisher removes the oxygen. A foam extinguisher aims to remove both, with the foam acting as a cooling agent and also a barrier to prevent further oxygen from reaching the fuel source.

Why do you need different fire extinguishers?

Not all fire extinguishers are suitable for all situations. Many fire extinguishers are specifically designed to be used against certain classes of fire. Using a fire extinguisher against the wrong type of fire not only has the potential not to put the fire out, but can even make the fire worse. To understand the different purposes for the various types of fire extinguishers, it’s important to know the different fire classifications.

Fires are differentiated into Classes A, B, D, C, Electrical, and F. Let’s take a closer look at each of these classifications.

Class A Fires

Class A fires are the kind you’re the most likely to encounter. They involve most varieties of solid combustible material, including wood, paper and textiles. Class A fires commonly occur in the home as well as in the workplace. Class A fires are combated effectively and cheaply by the use of either water or foam fire extinguishers.

Class B Fires

Class B fires are outbreaks involving flammable liquids. These include fuels such as petrol and diesel, but also paints, oils and alcohol. For Class B fires, a foam or dry powder fire extinguisher is recommended. Class B fires are a common hazard in workshops and garages. It’s important to avoid a water fire extinguisher for Class B fires as they can displace the liquid, spreading the fire rather than extinguishing it.

Class C Fires

Class C fires are caused by flammable or combustible gases. These include those used as fuel such as methane, propane, or natural gas. Even small leaks of these gases carry the risk of a quick ignition if they come into contact with an open flame or igniter. A powder fire extinguisher is the recommended choice for a Class C fire.

Class D Fires

Class D fires are mostly encountered in industrial settings and they refer specifically to fires resulting from flammable metals like magnesium. Metal fires aren’t especially common but industrial settings where metalwork is performed are at an increased risk of Class D fires. Class D fires are put out by specialist dry powder extinguishers.

Electrical Fires

Electrical fires are fires involving electrical equipment or appliances. These can occur at home, in the office, or anywhere that electrical equipment is in use. Due to the risk of electric shock, and further equipment damage, water extinguishers are not recommended for electrical fires. Instead, a CO2 extinguisher is the best choice, particularly when dealing with sensitive electronics due to the lack of residue CO2 leaves behind.

Class F Fires

Class F fires typically occur in professional kitchens or other spaces where oils are being heated to high temperatures, like in a deep-fat fryer. Due to the exceptionally high temperatures involved in these fires, a wet chemical extinguisher is the best option. The use of a fire blanket is also a good choice when dealing with cooking oil/fat fires.

Fire extinguisher types

Now that you are aware of the different fire classifications, let’s take a look at the different types of fire extinguishers needed to fight them.

Water Fire Extinguishers

Standard water jet extinguishers are an extremely cost-effective option, for fighting Class A fires. The majority of workplaces will require at least one water fire extinguisher. However, they aren’t particularly versatile.

They should never be used on an electrical fire as the water conducts electricity and can pose a risk of electrocution. Likewise, water fire extinguishers can displace any flammable liquids, causing the fire to spread rather than extinguishing it. 

The FireShield Water Plus Fire Extinguisher is a reliable, high-quality option that’s perfect for hotels, public places, and residential areas. Thanks to their lack of chemical additives, water fire extinguishers don’t leave any harmful residue, making them an excellent choice for anyone looking to maintain their fire safety without having a negative environmental impact.

You can recognise water fire extinguishers by their completely red colour.

 Water Mist

A common misconception is that water and water mist fire extinguishers are the same. In fact, they have quite different uses.

Water mist fire extinguishers contain ‘deionised water’. This is water that has been put through a process which removes all electrically conductive minerals. It’s similar to distilled water, but distilled water has had all impurities removed, while deionised water has only had dissolved minerals removed.

While a water mist fire extinguisher is equally suited to Class A fires as a water jet extinguisher, the process of deionising the water means that it has very low electrical conductivity, making it suitable for electrical fires. Water mist extinguishers are extremely versatile and capable of fighting the majority of fire classes.

Water mist extinguishers should not be used against Class D fires and not all of them can fight Class F fires involving cooking oils.

The FireShield Water Mist Extinguisher is a great choice for a wide range of settings thanks to its ability to reliably and effectively fight a range of fire classes, including electrical and Class F fires.

You may also see fire extinguishers labelled as ‘Foammist.’ These extinguishers use an agent that is 99% water and 1% foam. This allows it to form a blanket over the top of a fire, which means that, alongside the existing benefits of water mist extinguishers, it can effectively fight Class B fires.

Water mist fire extinguishers are entirely red and foammist extinguishers feature a cream panel across the front.

Foam Fire Extinguishers

Foam extinguishers are suitable for use on both Class A and B fires which makes them a popular choice for a lot of different environments, including offices, hotels, warehouses, and factories. The foam acts as a rapid coolant and prevents oxygen from reaching the fire.

Foam extinguishers work by smothering the fire and cooling via the water content which helps to prevent it from reigniting. The foam spreads across the surface of a liquid, making it extremely effective at tackling Class B fires.

The FireShield Foam Fire Extinguisher is trusted by businesses all over the country thanks to its range of sizes, compact design, and robust, corrosion-resistant construction that ensures it remains reliable even in harsh weather conditions.

You can recognise a foam fire extinguisher by its cream panel.

CO2 Fire Extinguishers

CO2 fire extinguishers are easily recognisable by their slimline shape. They work by displacing the oxygen in the air to suffocate the fire.

CO2 fire extinguishers leave no residue behind. This makes them a popular choice when protecting sensitive electrical equipment like fuse boxes and server units. CO2 extinguishers shouldn’t be used on Class A fires but they are an ideal choice when fighting Class B and Electrical fires.

When looking for a dependable method for fighting Class B and electrical fires, the FireShield CO2 Fire Extinguisher is the ideal choice. It not only fights fires extremely effectively, but the hard-wearing alloy that it’s made from is durable enough to stand up to even the harshest environments. It has even been tested for use in heavy-duty marine environments like container ships and oil platforms.

CO2 Fire Extinguishers can be easily identified by a black panel on the body of the extinguisher.

ABC Powder & Specialist Dry Powder Fire Extinguishers

Powder extinguishers come in many varieties. The FireShield Dry Powder Fire Extinguisher is great for use on Class A, B and C fires. Their versatility makes ABC powder fire extinguishers a popular choice in a range of settings.

For large workshops, forecourts, and other well-ventilated areas powder extinguishers are an excellent choice. Dry powder fire extinguishers are also very commonly used in vehicles, both private and commercial.

There are also specialist dry powder extinguishers that are formulated to deal with Class D fires, caused by flammable metals.

Powder extinguishers are distinguished by a blue panel.

Wet Chemical Fire Extinguishers

Wet Chemical extinguishers are used to put out Class F fires, which most commonly occur in commercial kitchens due to the presence of hot cooking oils. If your premises contain any form of deep fat fryer or chip pan, your insurance company will likely require you to install a wet chemical extinguisher.

Whilst they are specified for Class F fires, some brands of wet chemical extinguishers like the FireShield Wet Chemical Fire Extinguisher are also highly effective on Class A and C fires. Always check your extinguisher before use to confirm.

Wet chemical extinguishers feature a yellow panel.

Portable vs Non-Portable Fire Extinguishers

Portable fire extinguishers are the most commonly used type of fire extinguisher but they’re far from the only available option. Fire extinguishers are categorised by their total mass. If the extinguishing agent inside a fire extinguisher is 20kg or lower, it is classed as a portable fire extinguisher. This means that it is meant to be used by a single person.

However, for larger firefighting needs, a non-portable fire extinguisher may be a better option.

Wheeled Fire Extinguishers

Some environments simply have more significant fire protection needs than a portable fire extinguisher can handle. In that case, you may find that a wheeled fire extinguisher is a much better choice.

With a capacity of up to 100 litres, the FireShield Foam Wheeled Fire Extinguisher is ideal for meeting heavy-duty fire protection needs in settings like fuel stations, large warehouses, and manufacturing plants. Thanks to the wheeled trolley, this extinguisher can be operated by a single person, despite its size.

Automatic Fire Extinguishers

Automatic fire extinguishers are used in areas where a fire risk assessment shows that there are fire hazards, but there’s very little supervision or foot traffic. If a fire breaks out in an area like an engine room or server suite, it will often be too late by the time someone responds with a portable fire extinguisher.

The FireShield Automatic Dry Powder Fire Extinguisher works using a heat-sensitive glass bulb instead of a handle. When the air around this bulb reaches the target temperature, it breaks and the extinguisher starts working. This means that an automatic fire extinguisher can not only respond to a fire right away, it can stop it before it even gets started.

Not only does this allow you to put a fire out immediately, but you can install automatic fire extinguishers in areas that would otherwise be difficult to reach. Some automatic fire extinguishers are small enough to fit inside servers and fuse boxes.

Conclusion

The type of fire extinguisher that you need entirely depends on your specific fire safety needs. When deciding on the right fire extinguisher, you should always refer back to your Fire Risk Assessment. You need to consider the types of materials around you, what your fire hazards are, and who will be at risk.

If you still need some guidance to figure out which type of fire extinguisher you need, you can contact one of our fully qualified engineers on 03300580631 or get in touch with us online.