Fires can break out at any time, and when they do, having a fire extinguisher on hand can mean the difference between a small, contained incident and a major disaster. While we hope you’ll never need to use one, understanding fire extinguishers and how to use them is crucial for everyone. In this blog, we’ll break down everything you need to know about fire extinguisher—from types and classes to maintenance and proper usage.

What is a Fire Extinguisher?

A fire extinguisher is a portable device used to put out small fires. It consists of a pressurized container filled with an extinguishing agent—such as water, foam, dry chemicals, or CO2—and a nozzle or hose for directing the agent at the fire. Depending on the type of fire extinguisher, it can be used to tackle different kinds of fires, which is why understanding the classification of both fires and extinguishers is so important.

The ABCs of Fire Extinguishers

Fire extinguishers are categorized based on the types of fires they are designed to handle. In the U.S., the National Fire Protection Association (NFPA) uses a system to classify fire extinguishers into several groups:

• Class A: For ordinary combustibles like wood, paper, or fabric. These are common materials you’ll find in homes, offices, and schools.
• Class B: For flammable liquids such as gasoline, oil, or solvents. These are often encountered in kitchens, garages, or industrial settings.
• Class C: For electrical fires. Electrical fires can occur when wiring, outlets, or electrical devices overheat or malfunction.
• Class D: For combustible metals like magnesium or titanium. These fires typically happen in industrial settings.
• Class K: For kitchen fires, particularly those involving cooking oils and fats. These are high-temperature fires typically found in commercial kitchens or home kitchens with deep fryers.

The fire extinguisher label often includes a letter or a combination of letters and numbers (e.g., “ABC” or “2-A:10-B

“) to indicate which types of fires the extinguisher can be used on.

Types of Fire Extinguishers

Fire extinguishers come in various types, each designed to handle specific fire scenarios. Let’s look at the most common ones:

1. Water Fire Extinguishers (Class A):
   • These extinguishers use water to douse fires caused by ordinary combustibles like paper, wood, or cloth.
   • Do not use on electrical or grease fires—water can conduct electricity and make the fire worse.
2. Foam Fire Extinguishers (Class A & B):
   • Foam extinguishers are ideal for both ordinary combustibles (Class A) and flammable liquids (Class B).
   • The foam coats the surface of the fire, effectively cutting off the oxygen supply and cooling the material.
3. Dry Chemical Fire Extinguishers (Class A, B, & C):
   • These are the most versatile and commonly used fire extinguishers. They use a dry chemical powder (usually monoammonium phosphate) to smother fires in a wide range of classes.
   • It works by interrupting the chemical reaction in the fire triangle (fuel, heat, oxygen).
4. Carbon Dioxide (CO2) Fire Extinguishers (Class B & C):
   • CO2 extinguishers are typically used for flammable liquid fires and electrical fires.
   • These work by displacing oxygen and suffocating the fire. CO2 extinguishers leave no residue, making them ideal for use on electrical equipment.
5. Wet Chemical Fire Extinguishers (Class K):
   • Wet chemical extinguishers are designed specifically for kitchen fires, particularly those involving oils, fats, or grease (like deep fryer fires).
   • The agent reacts with the fats to form a soapy foam, preventing the fire from reigniting.

How to Use a Fire Extinguisher: The PASS Method

If you’re faced with a fire, knowing how to operate a fire extinguisher quickly can be lifesaving. Follow these steps using the PASS method:

1. P – Pull the pin: This is usually located on the handle of the extinguisher. Pulling the pin breaks the seal and allows you to discharge the agent.
2. A – Aim the nozzle: Point the nozzle or hose at the base of the fire, not the flames. The base is where the fuel source is, and putting the extinguisher directly on it will help stop the fire from spreading.
3. S – Squeeze the handle: Squeeze the handle to release the extinguishing agent. The more you squeeze, the more agent will be discharged.
4. S – Sweep from side to side: Move the nozzle in a sweeping motion from side to side, covering the entire base of the fire. Continue until the fire appears to be out, and make sure you have thoroughly extinguished it.

Fire Extinguisher Maintenance and Inspection

To ensure your fire extinguisher works when you need it most, regular maintenance and inspections are essential. Here are a few tips for keeping your fire extinguisher in top shape:

• Monthly Visual Inspection: Check the pressure gauge to ensure it’s in the “green” zone. Verify that the nozzle or hose is clear, and look for any physical damage or leaks.
• Annual Professional Inspection: Have a certified professional inspect and service your extinguisher once a year, especially if it’s a commercial or industrial model.
• Recharge or Replace After Use: Even if you only used the extinguisher briefly, it should be recharged or replaced as soon as possible.
• Check the Expiry Date: Fire extinguishers typically last for 5–15 years, depending on the type. After this period, it’s time to replace them.

Where to Place Fire Extinguishers

The placement of fire extinguishers is just as important as having them in the first place. Here are some general guidelines:

• At least one extinguisher on each floor of your home or workplace.
• Near potential fire hazards, like the kitchen, garage, or workshop.
• Easy to access: The extinguisher should be placed where it’s visible and easy to grab, not hidden behind furniture or locked away.
• Mounting height: For easy use, mount extinguishers at a height that’s within reach for most people (around 3–5 feet from the ground).

Conclusion

A fire extinguisher is a critical safety tool, and knowing how to choose, use, and maintain one can be a life-saving skill. By understanding the different types of extinguishers and their proper uses, you’ll be better prepared to handle small fires safely and effectively. Remember, though, that fire extinguishers are designed for handling small, contained fires. If a fire is spreading quickly, or if you feel unsafe at any time, evacuate immediately and call the fire department.

Keep your fire extinguisher accessible, inspect it regularly, and make sure everyone in your household or workplace knows how to use it. Safety first!