Types of Fire Extinguishers
Fire extinguishers are an essential part of any building’s safety equipment. They come in various types, each designed to tackle specific types of fires. In this blog post, we will explore the different types of fire extinguishers and their uses.
Classes of Fires
Before we dive into the types of fire extinguishers, it’s essential to understand the classes of fires. There are six classes of fires:
Class A: Fires involving ordinary combustibles like wood, paper, and cloth.
Class B: Fires involving flammable liquids like gasoline, oil, and grease.
Class C: Fires involving Flammable gases including butane, propane, methane and Liquefied petroleum gas (LPG).
Class D: Fires involving combustible metals like magnesium, titanium, and potassium.
Electrical: Fires involving electrical equipment such as wiring, computers, televisions.
Class F: Fires involving cooking oils and fats.
Types of Fire Extinguishers
Water Extinguishers (Class A fires)
Label Colour: RED
Water extinguishers are the most common type of extinguisher and are used for Class A fires only. They are filled with water and are designed to cool the fire’s fuel source, reducing the flames’ intensity. However, they should not be used on Class B, C, D, Electrical or F fires as the water can spread the fire or conduct electricity.
Foam Extinguishers (Class A and B fires)
Label Colour: CREAM
Foam extinguishers are designed for Class A and B fires. They are filled with water and foam concentrate, which creates a blanket over the fuel source, smothering the fire. Foam extinguishers should not be used on Class C, D, or F fires.
Carbon Dioxide Extinguishers (Class B and C fires)
Label Colour: BLACK
Carbon dioxide (CO2) extinguishers are designed for Class B and Electrical fires. They work by removing the oxygen from the fire, suffocating it. They are commonly used in electrical fires as they do not leave any residue and do not conduct electricity. CO2 extinguishers should not be used on Class A, D, or F fires.
Dry Powder Extinguishers (Class A, B, C, D* and Electrical fires if the equipment is less that 1,000v)
Label Colour: BLUE
Dry Powder extinguishers are versatile and can be used on Class A, B, C, and Electrical fires. They work by interrupting the chemical reaction of the fire, preventing it from spreading. There are two types of dry chemical extinguishers: ABC and BC. ABC extinguishers are filled with monoammonium phosphate and are the most common type, while BC extinguishers are filled with sodium bicarbonate. Dry chemical extinguishers should not be used on Class F fires or electrical fires where the equipment exceeds 1000v. *Class D Fires require a specialist L2 Metal Powder Extinguisher.
Wet Chemical Extinguishers (Class F fires)
Label Colour: YELLOW
Wet chemical extinguishers are designed for Class F fires, which involve cooking oils and fats. They work by creating a barrier between the fuel source and oxygen, preventing re-ignition. Wet chemical extinguishers should not be used on Class A, B, C, or D fires.
Servicing
Fire extinguishers are critical safety equipment that can save lives and prevent property damage in the event of a fire. It’s essential to choose the right type of extinguisher for the type of fire, as using the wrong extinguisher can be dangerous and make the situation worse. In order to be compliant with BS5306 extinguishers should be serviced annually.