Fire extinguishers have become the most crucial part of safety at home/office and other public places to save property and lives of people until the fire department reaches the place. However, not one type of extinguisher can suppress the fire started by all types of fuels. Therefore, different types of extinguishers came into existence.
Moreover, having suitable fire extinguishers at an organization is not enough; regular testing of the fire safety equipment is legally important in various countries to ensure that the safety equipment is in good working conditions. For example, if you belong to Sydney, Australia, it is mandatory to perform the Fire extinguisher testing Sydney after regular intervals to avoid any heavy penalties by the government. Before knowing about the different fire extinguishers, you need to understand the different fire classes.
What are the different fire classes?
Different flammable materials can ignite a fire. Therefore, to control the fire effectively, it is important to use suitable fire fighting equipment. There are a total of 6 types of fire classes.
Class A-Fire is caused by solid combustible materials like paper, wood, fabric, plastic and rubber.
Class B- Fire involving flammable liquids like petrol, paint, diesel and other oils.
Class C- Fire caused by flammable gases like hydrogen, methane, butane etc.
Class D- Fire caused by burning combustible metals such as potassium, aluminium, magnesium, and more.
Electrical Fires – Fire caused by electrical apparatus, but the fire changes its class once the electrical equipment is removed.
Class F-Fire involving cooking oils like butter, olive oil etc. It is typically a chip-pan fire.
Types of fire extinguishers and their uses
Carbon Dioxide (CO2) Extinguishers
The carbon dioxide extinguishers are suitable for Class B and electrical fires but are ineffective for class A fires. Therefore, these are meant to be at offices, computer server rooms and other buildings with electrical appliances. This fire equipment works by cutting the oxygen supply to the burning material and shower cold discharge to remove the heat.
These come with a black colour label on them. In addition, the carbon dioxide extinguishers are the cleanest fire safety equipment since they require no clean-up as these don’t leave any residue behind like the foam-based extinguishers.
Wet Chemical Extinguishers
Wet chemical extinguishers are suitable for Class F fires, such as in deep fat fryers. Also, they are appropriate to use for class A fires if foam or water extinguishers are not available at the moment. The wet chemical extinguisher quickly suffocates the flames and cools down the burning oil or butter.
Talking about its working, the chemical (potassium solution) contained in this extinguisher stops the reignition by forming a thick soap-based solution on the surface. The wet chemical extinguishers come with a yellow colour label. This type of extinguisher needs to be present in the home /commercial kitchens and canteens etc.
Dry Powder Extinguishers
The powder extinguishers are also called ABC fire extinguishers as they are used for Class A, Class B and Class C fires. Also, these can be used for stopping the fire caused by electrical appliances with 1000 V power, but these are inefficient in completely cooling down the fire, so there are chances that the fire can re-ignite.
The dry powder extinguishers are not recommended in closed areas or indoors unless no other option is available since they can cause breathing problems and visibility loss. These extinguishers should be placed at buildings with large boilers, flame-cutting/ welding businesses, and other premises involving flammable gases in any occupation. ABC dry powder extinguishers have a blue colour label.
Water Extinguishers
A water extinguisher is among the best and cost-effective fire safety equipment used to attack the Class A fire risk caused by organic materials like fabrics, cardboard, wood, and paper. However, avoiding using this extinguisher for the fire involves flammable gases and electrical appliances. A water extinguisher works by producing the microscopic water molecules, and the released molecules of water create a fog-like environment that helps suppress the fire.
These need to be placed at the exit of the residential buildings that are prone to class A fire risk. Also, any business dealing with organic materials like papers, textiles should have water extinguishers for safety. Water extinguishers have a bright red colour label on the container.
Foam Extinguishers
Form fire extinguishers are suitable for class A and class B fires but are least effective in fighting fires caused by flammable gases. However, these are not preferred when flammable metals and kitchen oils cause a fire.
Foam extinguishers release a foam-like substance that expands on getting in contact with air and looks like a blanket on the surface of the fire, which prevents the liquid from rising to the surface. Hence, it breaks the contact of fuel with the fire and cools it down. These should be available in schools, residential buildings, and businesses prone to class A and B fires. The label on the foam extinguishers is of cream colour.
Conclusion
Now, you have read about all kinds of extinguishers available in the market and their uses, so you can easily make a more informed choice when looking for suitable fire extinguishers for your house or office premises. To make sure you are making the right choice, you can take help from experienced professionals in the field.
