Our today’s Toolbox Talks topic is Classes Of Fires And Extinguishers, Fire is a destructive force that can cause extensive damage to property and even result in loss of life. Therefore, it is essential to have the right fire extinguisher for different types of fires. In this article, we will discuss the different classes of fires and the extinguishers suitable for each class.
Table of Contents
Classes Of Fires And Extinguishers
Ordinary combustible materials such as wood, cloth, paper, etc.
Flammable liquids such as grease, gasoline, lubricating oils, and other hydrocarbons.
Combustible metals like sodium, magnesium, aluminium, etc. and phosphoric substances.
Cooking oil or fat
Classes Of Fires
Class A Fire
This type of fire involves ordinary combustibles such as wood, paper, or cloth. Water is the most common extinguisher used for Class A fires. When water is applied to the fire, it cools the burning material to below its ignition temperature. Water extinguishers have a pressure that lasts for 2 minutes and can reach up to 40 feet.
Class B Fire
This type of fire involves flammable liquids such as gasoline, oil, and grease. The best extinguisher for Class B fires is the dry chemical powder extinguisher. The powder extinguishes the fire by smothering it, thus stopping the chain reaction. The pressure in the cylinder is generated by gas cartridges and can last up to 2 minutes, reaching 10-15 feet.
Class C Fire
This type of fire involves electrical equipment, such as appliances, motors, and transformers. The best extinguisher for Class C fires is the CO2 extinguisher. Carbon dioxide extinguishers remove or displace oxygen, making them ideal for electrical fires. CO2 extinguishers have a pressure that lasts for 15 seconds, and they are not suitable for distant fires.
Class D Fire
This type of fire involves flammable metals such as magnesium, titanium, and sodium. Specialized dry powder extinguishers are used to put out Class D fires. These extinguishers are designed to smother the fire and prevent the metal from reigniting.
Class K Fire
This type of fire involves cooking oils and fats. Wet chemical extinguishers are the best option for Class K fires. The wet chemical extinguisher creates a foam layer over the burning oil, isolating it from oxygen and extinguishing the fire.
Type of Fire Extinguishers
Dry powder fire extinguishers
Dry powder fire extinguishers are versatile and can be used on Class A, B, C, D, E fires. The powder smothers the fire by creating a barrier between the fuel and the oxygen.
Foam fire extinguishers
Foam fire extinguishers are used to put out Class B fires that involve flammable liquids such as gasoline, oil, and solvents. The foam creates a layer over the burning liquid, which prevents oxygen from reaching the fire and extinguishes it. Foam extinguishers are also effective for Class A fires involving ordinary combustibles.
CO2 fire extinguishers
CO2 fire extinguishers are used to put out fires that involve electrical equipment, such as computers and machinery. CO2 extinguishers work by displacing oxygen, which suffocates the fire. CO2 extinguishers are also suitable for Class B & Class E fires.
Water fire extinguishers
Water fire extinguishers are the most common type of extinguishers used to put out Class A fires only that involve ordinary combustibles such as paper, wood, and cloth. They work by cooling the burning material and lowering the temperature below the ignition point. Water fire extinguishers should not be used on fires that involve electrical equipment or flammable liquids.
Wet chemical fire extinguishers
Wet chemical fire extinguishers are used to put out on onlyClass F fires that involve cooking oils and fats, such as in a commercial kitchen. The wet chemical creates a barrier over the burning oil, which prevents oxygen from reaching it and extinguishes the fire.
let us discuss some additional factors to consider when choosing the right fire extinguisher.
Factors to consider when choosing a fire extinguisher:
- Location: The location of the fire determines the type of fire extinguisher that you should use. For example, if the fire is in a small kitchen, a wet chemical extinguisher would be ideal. However, if the fire is in a large warehouse, a dry powder extinguisher may be required.
- Size of the fire: The size of the fire determines the size of the extinguisher required. If the fire is small, a handheld extinguisher may be enough. However, if the fire is large, a larger fire extinguisher or a fire hose may be required.
- Maintenance: It is essential to ensure that your fire extinguisher is regularly maintained and serviced. This ensures that the extinguisher is in good working condition when you need it.
- Accessibility: Fire extinguishers should be easily accessible and located in visible and accessible areas. This ensures that they can be easily located in case of a fire.
Now that we have discussed the different classes of fires and the appropriate extinguishers for each, it is essential to remember a few safety tips when using a fire extinguisher:
- Always ensure that you are using the correct type of extinguisher for the fire.
- Always stand at a safe distance from the fire and approach it from a safe angle.
- Always aim the extinguisher at the base of the fire.
- Always sweep the extinguisher from side to side to cover the entire area of the fire.
having the right type of extinguisher can make a huge difference in putting out a fire. Knowing the different classes of fires and the suitable extinguishers can help you make an informed decision when purchasing a fire extinguisher. However, it is also essential to remember that prevention is better than cure. Always ensure that you have a fire prevention plan in place and practice fire safety regularly.