Types of Fire Extinguishers and When To Use Them

In the event of a fire at your petrol station, being prepared can be the difference between a minor site incident or extensive damage and harm to property and personnel. Most people have a good understanding of how to use a standard fire extinguisher, but many may not know that there are several types of extinguishers available, and that each type of extinguisher is designed to fight different types of fires. Knowing the differences and understanding how to determine what type of extinguisher to use is critical to proper fire emergency preparedness.

1. Water Extinguishers
Water extinguishers, marked with red labels, are one of the most cost-effective ways to fight Class A fires fueled by solid materials like paper, wood, and other textiles. These extinguishers are largely inexpensive to buy and come in four different varieties of dispenser: water jet, water spray, water with additives, and water mist or fog.

Water jet and spray extinguishers work by spraying a powerful jet of water at burning material, cooling it quickly and preventing reignitions. Water jet extinguishers should never be used to extinguish live electrical equipment.

Water mist and fog extinguishers work by applying water to fires in the form of mist, or fog. Droplets from these extinguishers are much smaller than those from water spray models. Smaller droplets have a larger surface area in relation to their size. The quicker droplets evaporate, the faster they are able to store heat energy. This makes them effective for cooling hot fires quickly. However, smaller droplets simultaneously weigh less, which means that the finer the mist from your extinguisher, the less powerful it may be.

2. Foam Extinguishers
Unlike water extinguishers, foam extinguishers, which are marked by a cream label, can be used on both Class A and B fires. This means they are effective on fires fueled by both solid textiles and contained liquids such as petrol or diesel.

While foam extinguishers can work to put out both classes of fires, they are most suited to liquid fires as they effectively seal the surface of the liquid and prevent flammable vapours from reaching the air. This starves the fires of oxygen and fuel, stifling it. Foam extinguishers should not be used to extinguish free-flowing liquid fires.

3. Powder Extinguishers
Powder extinguishers, marked with a blue label, are a good multipurpose option for fighting Class A, B, and C fires. Unlike water extinguishers, they can be used on electrical equipment. But though they are multipurpose, they do have a number of drawbacks.

Powder extinguishers do not contain cooling agents meaning fires are more prone to re-ignite. These extinguishers can also create low visibility or breathing problems and are not generally recommended for use inside buildings unless absolutely necessary.

4. Carbon Dioxide Extinguishers (CO2)
CO2 extinguishers, marked with a black label, are ideal for areas of your service station that contain a good deal of electrical equipment such as offices or storerooms. Unlike powder or foam extinguishers, they are good for use indoors as they do not obstruct visibility or leave behind residue. These extinguishers work by smothering the fire and cutting off the air supply until the fire is no longer burning.

5. Wet Chemical Extinguishers
Wet chemical extinguishers, marked by a yellow label, are suitable for use on Class F fires involving cooking oils and fats such as lard, olive oil, sunflower oil, maize oil, and butter. When used correctly, the wet chemical from the device rapidly subdues flame, cools the burning oil, and chemically reacts to form a soap like solution. This solution seals the surface of the liquid and prevents reignition. Though they are designed for primary use on Class F fires, they can be effective in fighting Class A and B fires as well.

6. Fire Blankets
The last type of fire extinguishing device is a fire blanket. Fire blankets are primarily for use on hot oil fires contained to receptacles such as frying pans or small deep fat fryers. They work by smothering the fire, cutting off access to the oxygen that fuels it. Because of their flexible design, they are also useful in the event that an individual’s clothes have ignited.

Choosing The Right Extinguisher Matters
When it comes to choosing the right fire extinguisher, it is important to know the type of fire you are dealing with. Different classes of fires require different extinguishing methods. In some cases, choosing the wrong type of fire extinguisher can be very dangerous or even make the fire worse, resulting in further damage and potential injury to those trying to fight it. By understanding and identifying what type of extinguisher is appropriate for the fire at hand, you will be able to deescalate dangerous situations before they grow or are made worse.

Staff Training
ServoPro Members can access staff training through our online training course, ServoSkills. By completing the ServoSkills training course, staff will be fully trained in how to determine the correct fire extinguisher to use and how to use it.

For more information contact Dan Armes on 0490 415 063 or [email protected]

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