Disclaimer: Do not continue reading if you are in an emergency. If a fire is growing quickly, call 911 and leave your home immediately. Small- and medium-sized fires can grow rapidly, engulfing a home in a matter of minutes. Act urgently.

Did you know different fires behave in different ways? Fire is fire, right? Wrong. There are at least five different types of fire, and each needs to be put out in a different manner. The fire types are grouped into categories based on the fire’s fuel source. Keep your home safe by keeping the relevant fire safety equipment nearby.

Whether it's your toaster on fire or your bookcase, knowing how to put out different fire types is an essential skill. That includes knowing how to put out a grease fire.

Class A fires involve common fuel sources like wood, paper, fabric, trash, and plastics. They’re the most common type of fire. These fires can progress very quickly, devouring nearby materials. One example of a Class A fire is a dumpster fire. In this case, the fire is contained, and there is no risk to human life.

In contrast, if you see a Class A fire in your home, you must use either water or monoammonium phosphate to extinguish it. Buckets of water will suffice for smaller fires. However, a continuous stream of water from a hose works well for larger fires.

Be careful of any combustible or hazardous material near the fire. These can explode at any point and transform the fire into a different class.

Class B fires result from an explosion of flammable liquids or gasses. Examples of flammable liquids include gasoline, kerosene, solvents, alcohol, oils, tars, and petroleum-based paint. Flammable gasses include butane and propane.

NEVER extinguish a Class B fire with water, as it will splatter the flammable liquids, spreading the flames. Rather, Class B fires must be smothered using a fire blanket or dry chemicals, like ammonium phosphate or pressurized carbon dioxide. The goal is to deprive the fire of oxygen, putting it out. Dry chemicals are also effective on Class A and C fires.

Class C fires are electrical fires. They are caused by faulty electrical equipment sparking, resulting in a fire. According to the US Fire Administration, over 20,000 electrical fires occur every year. Such fires are worsened when large-scale electrical power equipment is involved. But they can also be caused by something as simple as a space heater or faulty wiring.

So, what should you do if you see your toaster on fire?

In the case of a Class C fire, first, switch off the electrical power – it is working as a fuel source for the fire. Again, NEVER use water on a Class C fire. Water will trigger an electrical device to spark and will make the surrounding area more dangerous.

Instead, use a carbon dioxide (CO₂) extinguisher to suppress the flame. Dry chemicals will also work in such fires – though the current preference is for CO₂ extinguishers.

Class D fires are much rarer and are caused by flammable metallic substances like sodium, lithium, or potassium. You’ll most often find Class D fires occurring in a laboratory.

Water will only worsen a Class D fire, as it reacts with certain metals. The only method of extinguishing class D fires is to use a dry powder agent. These include graphite powder, powdered copper and sodium chloride. The goal is to absorb the heat and smother the fire.

Dry powder agents are not the same as dry chemical agents. Dry chemical agents can exacerbate Class D fires by fueling the reaction.

Class K Fires are perhaps the most dangerous. They occur due to grease, lard, oil, and animal and vegetable fats. Though Class K fires can occur at home, they’re most commonly found in commercial buildings and restaurants with a kitchen. However, if grease builds up around a stovetop or cooking food is left unattended, then a Class K fire can occur anywhere.

You should only use a Class K extinguisher to extinguish a Class K fire. Throwing water on the flames will cause them to explode or soar upwards. Class K fire extinguishers contain an alkaline mixture, such as potassium acetate, potassium carbonate, or potassium citrate. It forms a foam layer over the cooking oil, quenching the steam and smothering the flame.

If possible, turn off the stove immediately. This will reduce the heat fueling the fire. You can also cover a pan with a lid (using metal tongs) to deprive the fire of oxygen. If you do not have a Class K fire extinguisher, large quantities of baking soda or salt are suitable alternatives. Do not add any other kitchen ingredients, as you’re adding fuel to the fire.

That’s how to put out a grease fire.

Fire extinguishers are designed to be simple to use. Follow the PASS system:

Pull the pin.

Aim the nozzle from a safe distance at the base of the fire.

Squeeze the handle slowly.

Sweep the nozzle from side to side until the fire is out.

Not every fire is easily extinguished. If, for whatever reason, the fire won’t go out or you’re not confident in tackling it, alert everyone in your home to the problem. If there’s an alarm, pull it. Make sure everyone leaves the building, and alert the authorities as soon as possible.

Stand a safe distance from the home, and wait for help to arrive. Do not continue to tackle an out-of-control fire or wait too long to call the authorities. Remember, time is fuel – the longer you wait, the more the fire will burn.