How Do Fire Extinguishers Stop Fires?
Learn how fire extinguishers work by disrupting the fire triangle and stopping combustion. Perfect for young scientists eager to understand the world through fun, engaging content.
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February 26, 2025
4:03 listen
Fizz, Pop, Wow!
Fire needs three key elements to burn: heat, fuel, and oxygen—known as the fire triangle. Fire extinguishers work by removing one or more of these elements, with different types targeting different sides of the triangle. Some cool the flames, others smother the fuel, and some push away oxygen.
What Keeps a Fire Burning?
To understand how to stop a fire, we need to know what keeps it going. Fire needs three things: heat, fuel, and oxygen. Scientists call this the fire triangle:
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Heat – like a match or spark
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Fuel – like wood or paper
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Oxygen – from the air
Remove any one of these, and the fire goes out!
How Do Fire Extinguishers Work?
Fire extinguishers are like firefighters in a can. They work by removing one part of the fire triangle:
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Water extinguishers cool down the heat.
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Foam and dry chemical extinguishers smother the fuel.
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Carbon dioxide (CO₂) extinguishers push away the oxygen.
Each type fights fire in a different way—but they all break the triangle!
Try It: Fire-Stopping Science
Test how to safely stop a flame with these grown-up-approved experiments.
Try It: Fire-Stopping Science
Materials Needed:
- Small candle
- Glass jar
- Spoon
- Baking soda
- Adult supervision
Steps to Follow:
- Light a candle with an adult's help.
- Blow on it to push away heat and oxygen—fire goes out.
- Light it again. Now place a glass jar over it—watch it run out of air.
- Light a new candle. Sprinkle baking soda on it—it goes out instantly!
- Baking soda releases CO₂, just like a real extinguisher!
Your Challenge
Try the baking soda experiment with an adult’s help and see how fast the flame disappears. Then next time you see a fire extinguisher, check the label—can you tell what type it is and how it works?
Your Challenge
Try the baking soda experiment with an adult’s help and see how fast the flame disappears. Then next time you see a fire extinguisher, check the label—can you tell what type it is and how it works?
Key Takeaways
- Fire needs heat, fuel, and oxygen to burn—this is called the fire triangle.
- Fire extinguishers work by removing heat, fuel, or oxygen.
- Different extinguishers use water, foam, chemicals, or CO₂ to stop fires.
- You can safely explore how fires go out using candles, jars, and baking soda (with an adult's help!).