Be it residential premises or commercial establishments, fire extinguishers are an absolute must. A fire can spark anytime and could lead to loss of life and property if not controlled on time. Fire extinguishers are the go-to equipment during the initial stages of fire fighting.
It’s interesting to note that a fire can spark from anything (flammable gas, electricity, cooking oil, etc.) and depending on the source, you must deploy a fire extinguisher. Read on to know the various types of fire extinguishers and the class of fires under which they should be used. Let’s begin.
A foam fire extinguisher is the most common type of extinguisher that’s used to douse fires caused by organic materials (paper, wood, fabric, etc.) and flammable liquids such as petrol and paint. Note that flames caused by the former fall under the category of class A fire while the latter is categorised under class B. The label colour for the foam extinguisher is cream.
This fire extinguisher sprays a type of foam that expands upon coming in contact with air. It thus forms a blanket over the fire. This blanket creates a barrier between the fuel and the flame, helping to put off the fire. As the foam is mixed with water, it has a cooling effect.
Foam extinguishers are extensively used in establishments where the building is constructed with organic materials or in places where these materials are likely to be found, such as warehouses, hospitals, schools and premises storing flammable liquids. Ideally, they should be placed on the exits of floors identified as a potential risk for class A and class B fire.
A water extinguisher is used to fight class A fire and has a bright red label. This type of extinguisher contains water with nitrogen or carbon dioxide, acting as a propellant. The working mechanism of this type of extinguisher is pretty simple. It removes the heat from the fire and cuts off its oxygen supply.
The water in the extinguisher has a cooling effect on the burning fuel. This causes the fuel to burn at a slow rate until the flames are totally doused. Buildings and establishments made of organic materials or those that house them need to install water extinguishers. You can also use this extinguisher in a domestic setting, such as a bedroom or living room.
This extinguisher needs to be placed at the floor exit that’s identified for class A fire risk. However, note that you must not use this extinguisher for electrical fires as water is a good conductor of electricity. Simple and easy to use, it’s easy to refill and is environment-friendly.
This extinguisher discharges deionized water in the form of a spray that forms a mist curtain. When released, the water gushes through a unique spray nozzle in microscopic particles. These particles provide an intense cooling effect and decrease the oxygen supply flaming the fire.
You can use a water mist fire extinguisher to fight class A and class C fires. Class C fires are mostly caused by flammable gases such as butane and methane. This extinguisher is suitable in a setting like a server and electrical rooms, hospitals, old buildings, etc.
It’s easy to activate this extinguisher, and since no toxic fumes are released, it keeps the people safe operating it.
A dry powder extinguisher is also known as an ABC extinguisher, and you can use it to fight class A, B and C fires. Fires caused by flammable liquids such as spirit, petrol or paint falls under class B. This extinguisher sprays an extremely fine chemical powder that’s mostly mono ammonium phosphate. Other ingredients include sodium bicarbonate and potassium bicarbonate.
This powder acts as a blanket over the fire and douses it. The label colour of this extinguisher is blue. Since the fine powder is not a conductor of electricity, it seamlessly breaks the chain reaction in a liquid or gas fire. This is something that a water extinguisher can’t do. While installing this extinguisher, you must see that the area is not enclosed as it’s pretty easy to inhale the powder present in it.
A dry powder extinguisher is ideal for businesses involved in flame cutting. Also, large boiler rooms where flammable gases are present should install this extinguisher. Note that this extinguisher leaves a lot of residue after being used, which can be difficult to clean.
This is another common type of fire extinguisher that’s designed exclusively for fighting class F fires. These fires are caused by cooking oils. A wet chemical fire extinguisher contains potassium that lowers the fire’s temperature, thus preventing it from spreading.
When you use it, potassium sprays out in the form of fine mist, reacting with the oil present in the fire. Upon reaction, it creates a soapy layer on the surface that cools and extinguishes the fire. However, note that you shouldn’t use this extinguisher to douse flames involving electrical appliances.
This fire extinguisher must be present in kitchens and commercial canteens where there’s a presence of a high amount of cooking oil. One of the major advantages of using this extinguisher is that its low pressure eliminates the risk of oils splashing out, thus preventing burns.
Also, cleaning up after use is easy and quick. However, note that eyes and skin can become a little irritated after its usage. At the same time, as the solution is alkaline, it can corrode surfaces such as aluminium.
This fire extinguisher contains a mixture of gaseous carbon dioxide and liquid and is primarily used for fighting electrical fires. You can easily identify this fire extinguisher by its hard horn. The pressure is so intense that dry ice may shoot out of the horn when used. Apart from extinguishing electrical fires, you can also use them to combat class B fire caused by flammable liquids.
Its working mechanism is simple. It displaces the oxygen flaming the fire. When carbon dioxide is released from the extinguisher, it forms a cloud that reduces the oxygen around the fire and stops it from burning. Once carbon dioxide is discharged, it begins to spread and create a cloud.
Upon dousing the fire, the gas dissipates in the atmosphere without leaving any trace. This extinguisher generally has a black label and must be placed near the source of fire risk and exits. Note that you must avoid contact with bare skin while using this extinguisher as it may result in frostbite. The carbon dioxide is extremely cold.
This type of extinguisher is a gaseous type suppressant. It’s stored in liquid form and when sprayed hits the air converting into a gas form that cuts the supply of oxygen, fuelling the fire. This extinguisher is suitable for combating class A and B fires. You can also use it to fight electrical fires.
The gas present in it is Halon that has a very short atmospheric life. It leaves no residue and this makes it quite eco-friendly. As the gas is non-conductive and clean, it’s ideal for installing in places where there are many electrical pieces of equipment.
Irrespective of the fire extinguisher you use, there are certain things common for all. They are:
Lastly, you must know how to use an extinguisher in times of need. While the instructions are given on the body, it’s advisable to carry out a mock practice so that you can quickly use it when required.