1. Call for help before attempting to extinguish a serious fire. The fire may take hold much faster than you’re capable of dealing with it, and if help is on the way, it removes one less concern for you.

• Call, or have someone else call, 911 as soon as possible. Ask for the fire service to come immediately, giving your address and a brief description of the type of fire.
• Check that all other people are out of the house and have them remove pets as well. Check that they’re all assembled at a safe meeting point. Do not allow children to attempt to use a fire extinguisher or control a fire in any respect whatsoever.
• Realize that reacting to a fire requires a sound process of decision-making that children and some adults may not be capable ofcoping with their panic. Prior training on correct use can alleviate some of the concern here.

2. Check for your own safety before starting to extinguish a fire. There are some key things to check for before you start fighting a fire using a fire extinguisher:

• Are you physically capable of extinguishing a fire? Some people have physical limitations that might diminish or eliminate their ability to properly use a fire extinguisher. People with disabilities, older adults, or children may find that an extinguisher is too heavy to handle or it may be too difficult for them to exert the necessary pressure to operate the extinguisher.
• Look for your exit points. Ensure that there is a clear exit for immediate escape should this become necessary. At all times, keep your mind focused on the availability of a safe retreat. If this is threatened at all, leave at once. The US National Fire Prevention Association recommends that you install fire extinguishers close to an exit point, to enable you to keep your back to the exit when you use the extinguisher; this ensures that you can make an easy escape if the fire cannot be controlled.
• Do not attempt to put out a fire where it is emitting toxic smoke; if you suspect or simply don’t know if the smoke is toxic, leave it to the professionals.
• Check for structural safety of the building, in case burning walls, floors, or rafters pose a risk to your safety.
• If you have more than one fire extinguisher, consider asking another mature and responsible person to use it in tandem with you.
• Remember that your life is more important than property, so don’t place yourself or others at risk.

3. Assess the fire. Only a contained fire should be fought using a fire extinguisher. Portable fire extinguishers are valuable for immediate use on small fires because they contain a limited amount of extinguishing material, which needs to be used properly or it will be wasted. For example, when a pan initially catches fire, it may be safe to turn off the burner, place a lid on the pan, and use an extinguisher. By the time the fire has spread, however, these actions will not be adequate, and only trained firefighters can safely extinguish such fires.

• Make a quick commonsense assessment about the utility and safety of using a fire extinguisher for the fire you’re experiencing. Obviously, a fire extinguisher is overkill for a candle but it’s useless when the whole house is on fire. A fire in a wastepaper basket, however, is another suitable candidate for fire extinguisher use.
• Use your instincts. If your instincts tell you the fire’s too dangerous to tackle, trust them.

4. Check the type of extinguisher. In the USA, there are five main classes of fire extinguisher (note that the classes and nomenclature can vary from country to country): A, B, C, and the less common classes D and K. The extinguishing agent might be water, dry chemical, halon, CO₂, or a special powder.

• Class A: This is suitable for cloth, wood, rubber, paper, various plastics, and regular combustible fires. It is usually filled with 2 1/2 gallons (9.46 litres) of pressurized water.
• Class B: This is suitable for grease, gasoline or oil-based fires is usually filled with a dry chemical. Extinguishers smaller than 6lbs (2.72kg) are not recommended.
• Class C: This is suitable for electrical fires caused by appliances, tools, and other plugged in gear. It can contain either halon or CO₂. Halon 1211 and 1301 is very expensive and depletes the ozone layer, but it is being replaced by non-depleting agents such as FM200. Note that halon is now illegal in numerous jurisdictions.
• Class D: This is used for water-reactive metals such as burning magnesium and will be located in factories using such metals. It comes in the form of a powder that must cover the material to extinguish it.
• Class K: This contains a special purpose wet chemical agent for use in kitchen fires and deep fryers to stop fires started by vegetable oils, animal fats, or other fats started in cooking appliances.
• Note that many fire extinguishers will work on a combination of fire classes. You’ll need to decide quickly on what type of fire you have and ensure that your fire extinguisher is compatible with the fire you are attempting to extinguish. An all-purpose ABC dry chemical (10lb/4.5kg) extinguisher is a safe bet for most fires, especially when you’re not sure of the fire’s origins.

5. Ready the fire extinguisher. Almost all fire extinguishers have a safety pin in the handle. This pin usually looks like a plastic or metal ring, sometimes colored red, that is held in place by a plastic seal. The distinctive features will vary depending on the type of fire extinguisher you have. You must break the seal and pull the safety pin from the handle before you can use the fire extinguisher by squeezing the lever, which discharges the fire extinguishing agent.

• It helps if you ensure that you’re familiar with how your fire extinguisher works before being placed under pressure; take time to read over its instructions after you’ve read this article. Familiarize yourself with its special features and parts. Different extinguishers rely on different methods of use: be aware of this in advance of having to use them.

6. Aim for the base of the fire. Shooting into the flame is a waste of the fire extinguisher, as you’re not putting out the source of the flames. It’s vital to stop the fire at its source, or to remove or dampen the fuel from the fire, in order to put it out. By focusing the extinguisher’s spray at the base of the fire or the source, you’re extinguishing the fuel.