Types & Classes
Fire extinguishers are not simply just devices to put out fires – it is important to know that their applicability depends on the type of fire as well. Fire extinguishers come in 5 different categories and each of them needs to be used depending on the type of fire.
There are five main extinguisher types:
Each type has its own unique Colour code to easily distinguish the media inside of the Extinguisher. Water (Red), Foam (Cream), Powder (Blue), Co2 (Black) & Wet Chemical (Yellow)
These different Extinguisher types cover different types (Classes) of Fire. Picking the correct extinguisher to cover your risks is essential. Our chart below gives an understanding of which type of extinguisher covers which risk, there are sometimes exceptions to the rule with special versions of the five types but as standard this is a good point to start.
Class A – Combusitble Materials
Class B – Flammable Liquids
Class C – Flammable Gases
Class D – Metal Fires
Class E – Electrical Equipment Fires
Class F – Cooking Oil Fires
Class A fires are the ones that come from combustible materials, such as fires involving textiles, straw, or paper.
Class B fires characterise the flammable liquid fires that involve petrol, fats, or tar.
Class C fires are produced flammable gas, such as fires involving methane, propane, or natural gas.
Class D fires come from flammable metals and involve fires involving aluminium, metal, and potassium.
Class F represents the cooking-related fires, such as fires involving deep-fat fryers or domestic pans.
Electrical Fires, a special category that includes all the fires produced by electrical appliances and components.
Water Mist Extinguishers
Water Mist Extinguishers offer excellent coverage against A,B,C,E & F Classes of Fire. Its unique supersonic nozzle creates a highly effective cooling blanket. No additives are required to achieve these excellent ratings only de-ionised water, making this extinguisher environmentally friendly.
Also should the extinguisher need to be used in the event of a fire the collateral damage is reduced due to it purely being de-ionised Water
Using the Wrong Extinguishers
All fires act in different ways which are the reason why they divided into separate categories. There is no one size fits all and it is important to know how each fire should be managed in order to avoid any risks. If the wrong extinguisher is used to put off the fire, the effect could be the exact opposite. For example, using a water extinguisher on a Class F (combustible-related fires) could produce an explosion of steam and the expulsion of oils and fats could further take place.
A Guide to Using the Right Fire Extinguishers
As a leading British Manufacturer of Fire Extinguishers, we want to ensure that our customers understand the correct applicability of each fire extinguisher for their requires jobs. In order to avoid any risks, the guide below clarifies the different uses of each fire extinguisher and how they should be used in different scenarios.
One of the most popular extinguishers that most people are familiar with is the Water-based extinguisher. It is used on Class A fires (combustible materials). While they are very effective, their scope can be a problem. When using this extinguisher on a fire, any electrical components must be avoided as water is a great conductor of electricity. The water-based extinguishers are easily identifiable by the bold, light-coloured WATER text displayed on side of the container.
The Aqueous film-forming foam (AFFF) fire extinguishers are designed to tackle two different fire classifications: Class A (combustible materials) and Class B (flammable liquids). The reason why they are very effective lies in their ability to produce a ‘’blanket’’ of foam. That further that stops the oxygen to fuels the fire to expand or reignite.
This type of extinguisher can be recognizable by the word “FOAM” in large letters on the label.
Used on Class A (combustible materials), Class B (flammable liquids), and Class C (flammable gas) fires, the ABC Powder Extinguisher can also be used on electric fires. However, the powder might leave a residue that could potentially be harmful to the electrical components. It is also recommended to use these extinguishers in large spaces, as opposed to enclosed ones, in order to avoid any risks of inhalation.
The ABC powder extinguishers can be identified by their distinctive blue label.
The Carbon dioxide extinguishers are Class B (flammable liquids) rated. The way they function is by preventing the supply of oxygen to further reach the fire. This, in turn, minimises the risk of fire spreading and it will put it out in a quicker time. They can also be used on Class C (flammable gas) and are extremely effective on electrical fires.
If the Co2 Extinguishers are used in small space that does not have adequate ventilation, they could cause hypercapnia (CO2 poisoning). Users should be extremely cautious of this risk when using a CO2 extinguisher.
Used on most fire types, the Water mist Extinguishers are considered to be great “all-rounders”. They should not be used on Class D (flammable metal) fires. However, they are suitable to be used on electrical fires and that is due to the mist they have. The substance is de-ionised water which means it won’t conduct electricity, making it safe to use.
The Wet Chemical fire extinguishers have been designed to tackle Class F fires which involve combustible cooking materials such as fats and oils. They can also be used on Class A (combustible materials). The Wet chemical extinguishers use a special lance applicator nozzle that acts as a barrier between the oxygen source and the fire’s fuel.
They are easily recognised by the bright yellow label on the container.
Used for Class D (flammable metal) fires, the specialist dry powder extinguishers are highly specialist in nature. They should be used by people that received dedicated training in order to endure they are being used correctly and effectively.
Deciding on which Fire Extinguisher is right for you
Choosing the right extinguishers might be difficult when there are so many categories and types. Before deciding on which one you might require, think of the following:
What is the area you’ll be buying the extinguisher for like?
For example, kitchen space is likely to experience Class F (cooking-related fats and oils) fires, while a barn would be more likely to experience Class A (combustible materials) fires.
What fires are most likely to break out in that area?
So for a kitchen, you would opt for extinguishers that can tackle Class F fires – for example, water mist or wet chemical extinguishers. For a barn, you could opt for a water, AFFF foam, water mist, or ABC powder extinguisher.
How to choose the best fire extinguishers for your workplace?
The type of fire extinguisher that would best suit your workplace depends on the type of fire hazards uncovered during your latest fire risk assessment. For example, an office building is likely to require a foam or water fire extinguisher for common fires, as well as a CO2 fire extinguisher that can be used on electrical equipment fires. A commercial kitchen, on the other hand, may require a wet chemical fire extinguisher in case of a fire involving cooking oil.
How do fire extinguishers work?
Fire extinguishers break the connection between the three elements of the fire triangle – oxygen, heat and fuel. Most fire extinguishers work by separating the fuel from the oxygen. Different substances must be used to effectively cover different fuels which is why the various classes of fire extinguishers exist.
How many fire extinguishers do I need?
As a general rule, there must be at least two class A fire extinguishers on each floor. However, the exact requirements of your premises will be determined during the fire risk assessment. This is why it’s important to hire an experienced fire inspector to do the job and ensure that your building is safe.
Do I need to designate a fire warden?
Yes, it’s a legal requirement in the UK for every business to appoint fire wardens. There must be at least one trained fire warden present on each floor of the building.
Why are fire extinguishers important?
First and foremost, the fire extinguisher is a key element of your fire protection system and it can save lives in the event of a fire incident. In addition to that, as crucial fire safety equipment, fire extinguishers must be provided and it’s your legal responsibility as the employer to do so. Failure to comply with the fire health and safety regulations may result in fines and imprisonment.
If in doubt regarding your fire extinguisher requirements, please do not hesitate to get in touch with us for further advice regarding your purchase!