How to Use a Fire Extinguisher

Having a fire extinguisher in your home is a great way to reduce the risk of injury or death during a fire. But it’s important to know exactly how to use one before you actually need to, so that when disaster strikes you don’t make a simple mistake that could be fatal. Read and keep the operating instructions that came with your fire extinguisher, and review them during your household’s regular evacuation drills.

Fire extinguishers come in a variety of types, with different ratings for different classes of fires. When selecting an extinguisher for your house, choose one rated for your most common types of fire. For example, a class A fire extinguisher is suitable for paper, wood and other ordinary combustibles such as clothing. A class B fire extinguisher is suitable for flammable liquids such as oil or gasoline. A class C fire extinguisher is suitable for electrical fires. And a class D fire extinguisher is suitable for burning metals such as iron, copper, aluminium or magnesium.

There are also a number of different hand-held fire extinguishers, such as carbon dioxide (CO2) extinguishers which emit pressurised CO2 gas into the air, or dry chemicals that release powdered materials that smother the fire. There is also a water mist type that cools the flames by spraying a fine mist of water, which can be particularly useful in kitchens for Class F fires caused by fats and oils.

Before using any fire extinguisher, check that it is working by observing that the levers move freely and are not blocked by dirt or debris. Also, check the pressure gauge to see if the pressure is at or near capacity. If it is, then the extinguisher needs to be recharged.

The simplest and safest fire extinguisher to maintain is the water extinguisher. These are usually a cylinder with a handle or lever at the top which, when depressed, releases a stream of water into the flames. These can be used on class A, Class B and some class D fires. They are easy to operate and very effective, but can be difficult to aim and must not be used on active electrical equipment or metal fires.

Another option is the AFFF, or aqueous film foam concentrate, fire extinguisher. These have a higher rating than pre-mix models and contain an AFFF concentrate in a disposable cartridge which is mixed with water upon discharge. These are available as solid charge models with a hose or as a branchpipe nozzle. These are no longer produced in the UK due to environmental concerns but can be obtained from specialist suppliers outside the country. There are also electronic systems that constantly monitor an extinguisher’s physical presence and internal pressure and will notify the user if it is due for inspection or service. These systems can be wired to a building or used wirelessly and are often found in workplaces such as hospitals, warehouses and office buildings. In these cases, the system will be linked to a central computer to ensure all extinguishers are up to date.