Fire extinguishers play a very important role in first aid firefighting. They can mean the difference between a small fire being put out straight away or the fire service being called. That is why it is important to know about the different types of fire extinguishers and their uses.
An essential point to know is what fire class the extinguisher is able to put out. Fires are split into classes depending on the type of material and/or fuel used in combustion.
There are many types of fire extinguishers, for example Powder Fire Extinguishers. These are one of the most effective types of Fire Extinguisher available as their compact size and high performance makes them perfect for high-risk areas where space is limited. When pointed in the direction of a fire, compressed nitrogen propels the powder extinguishing agent over, and starves the fire of oxygen which prevents it from burning or reigniting. Powder fire extinguishers are suitable for class A,B,C and electrical fires. They can be recognised by their blue label stating: 'Powder'.
Another type of fire extinguisher are Automatic ABC Powder Fire Extinguishers. Like powder fire extinguishers, they are suitable for use on class A, B, and C fires. As the name states, these are automatic and therefore provide round the clock protection as they spray dry extinguishing powder automatically as soon as a fire is detected.
This is thanks to a red glass bulb that is filled with heat-sensitive liquid. When the liquid heats up, it expands and once it reaches 68°C the bulb breaks and the extinguishing powder is sprayed onto the surrounding area. This swift, automatic fire suppression means that the risk of a large fire, with the possibility of injury or fatalities is avoided, and valuable stock, equipment and machinery is protected.
Water Fire extinguishers are suitable for use on class A fires. This is because the pressurised water that is released from the extinguisher is able to permeate into the core of the burning material to cool them, therefore stopping the fire whilst also putting out any flames. The low toxicity of Water Fire extinguishers means they are more environmentally friendly, economical and suitable for use near children or vulnerable people.
Some types of water fire extinguishers have additives which makes water lose its surface tension which allows it to be immersed better into burning materials and therefore making the extinguisher more size effective. They can be identified by their white label stating 'Water'.
An additional type of fire extinguishers is Foam Fire Extinguishers. These are suitable on both Class A and Class B fires. Some foam extinguishers have passed the 35kV conductivity test, which means they are safe for accidental use on electrical equipment. They can be identified by their cream label stating 'Foam'.
They work in a similar way to water fire extinguishers in the sense that they are water-based and therefore cool down the temperature; but they also have an addition of AFFF which stands for 'Aqueous Film Forming Foam'. This foam envelops the fire and creates a seal for flammable vapours which stops the surface of flammable vapours reacting with the flames. Foam fire extinguishers are non-toxic and non-damaging to materials which makes them perfect for use in multi-hazard spaces such as offices, warehouses and commercial spaces.
Another type of non-damaging fire extinguishers are CO2 fire extinguishers. They are perfect for use in areas with delicate machinery and/or equipment as they leave behind no residue. This is because pure carbon dioxide is used to put out fires. The canister contains liquid CO2 and when it is ejected, it displaces the oxygen which the fire needs to burn and therefore puts out the fire. This type of extinguisher is suitable for use on Class B and electrical fires. It can be identified by its black label stating ‘CO2’.
A new type of fire extinguisher is known as Lithium Battery Fire Extinguishers. They are designed to be used on small fires that are caused by lithium batteries found in mobile phones, tablets and other similar devices.
These types of fires are caused when a lithium-ion cell overheats and are hard to put out with water or other fire-extinguishers as they are able to reignite even after the original fire is extinguished. They work by dispersing AVD (Aqueous Vermiculite Dispersion) compound in a fine water mist. This stops the fire because it halts the dangerous reaction that is occurring in the cells whilst the cold-water mist acts as a cooling agent.
This new type fire extinguisher allows lithium battery fires to be put under control quickly as they are very dangerous and can reach temperatures of 800ºC. It is also environmentally friendly as AVD is made from vermiculite, a naturally occurring mineral which allows this extinguisher to be used in a variety of places such as battery recycling facilities, public services and in goods distribution.
Finally, a fire blanket is a good option to put out small fires quickly and easily. Although they are designed for single use, they are fast and easily released and can be accessed quickly during an emergency. Fire blankets are most effective for use on small fires, for example that have been caused by cooking oil. They are also safe to wrap around a person in a clothing fire. They work by smothering the fire and depriving it of oxygen so it cannot spread or get any bigger. Fire blankets come ready folded and packed which allows them to be stored easily, and all comply with legal fire safety obligations. They are also available in a range of sizes from 1m x 1m to 1.8m x 1.8m.
In summary, fire extinguishers are a must have in any high or multi-risk space. All fire extinguishers come in a variety of sizes which makes them suitable for use anywhere as they can be easily stored. By having the ability to control small fires lives are protected, there is less chance of damage being caused to stock, equipment and buildings and they limit the amount of pollution that is caused by smoke and burning debris which is great for the environment.