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Fire Extinguisher

Keep your home and family safe

Done in 15 minutes
Skill level easy

With a few cheap things from your household, you can make a foam fire extinguisher that helps you to put down small, starting fires quickly. If you can’t afford an industrial fire extinguisher, this might be a good hack for you.

Demonstration of fire extinguisher
Demonstration of fire extinguisher

What kind of fires can you put down with the fire extinguisher?

Class A fires: Cardboard, wood, plastic, cloth Class B fires: flammable liquids or gases, for example petroleum, propane, gasoline, kerosene

⚠ Caution!

  • NEVER use the fire extinguisher for burning oil pots. Use the lid instead
  • Do not inhale vinegar. Do not target foam at people.
  • Keep away from children. Do not drink.
  • Do not throw bottle into fire - this won’t work.
  • Making, storing, using at your own risk.
  • No guarantee for effectiveness in the case of fire.

Published under CC:BY-SA by


Authors · Desania Govender, Yandisa Sojola, Marlene Lerch

What you need

Also good to have

How you make it

Make a hole in the cool drink bottle

Heat the top of a nail to burn a hole into the upper part of your bottle. To avoid burning yourself, put the nail onto a stick or a cork. You can also use pliers for this.

Cover the hole with tape

Cover the hole in the bottle with a strip of water-resistant duct tape. Make sure that the bottle is dry and that the tape sticks tightly. If the tape is loose, the life time of the fire extinguisher is shorter.

Label the bottle

Make a note on the bottle when the extinguisher was made. Label the bottle with today’s date.

Put water into the bottle

Put 750 ml of clean water into the bottle. That works best if you use a funnel.

Chris from dooiy

You have to mix the vinegar and water always in a 1:1 ratio. If you don’t use a 2 litre bottle, adapt the amount of liquids. Also important: Keep the liquid level well below the covered hole

Put vinegar into the bottle

Put the same amount of vinegar into the bottle (750 ml).

Put dishwashing liquid into bottle

Put 2 bottle lids of dishwashing liquid into the bottle.

Prepare plastic bag

Cut the plastic bag at the seams into 2 sheets. Be careful not to cut holes into the sheets.

Create a bag by placing one of the plastic sheets in the center of the bottle, then gently push the sheet into the bottle to a depth of about the length of your index finger. Be cautious not to tear the plastic sheet.

Make sure you use only one sheet and it is thin, otherwise it will be more difficult to get the bag out, when you need to use the fire extinguisher.

Put bicarbonate of soda into the plastic bag

Put 1/4 cup (~75g) bicarbonate of soda into this bag. You can use a funnel and stuff it carefully with a pen or stick. Make sure that the bicarbonate of soda does not get wet.

Close the bottle

Pull the bag up as high as you can without the bicarbonate falling out again. Make sure that the bag with the bicarbonate does not hang down into the vinegar.
Close the bottle with the lid tightly.

Prepare lash and remove rest of plastic bag

Remove the overhanging parts of the plastic bag. Leave one part of the plastic bag on one side as a lash.

Renew your fire extinguisher regularly

You should renew your fire extinguisher regularly to make sure that it is working. We recommend to make a new one every 6 months.

Do not throw the old fire extinguisher away. You can still use the liquid in the bottle as household cleaning detergent. You can use the bicarbonate of soda to clean water containers.

How you use it

Remove the tape and put your finger on the hole in the bottle

Open the bottle

Hold the lash of the plastic bag and let the bicarbonate of soda fall into bottle

Pull the plastic bag out of the bottle

Quickly close the bottle again and shake it

⚠ Be careful: a lot of pressure develops. Target the hole towards the fire

Remove your finger from the hole

Put down the fire with the foam that comes out of your fire extinguisher

Always aim at the bottom of the fire.

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Tips and Tricks

The fire extinguisher is cheaper if you make more than one, because you can buy vinegar and bicarbonate of soda in bulk. Ask your neighbours and make fire extinguishers together. If everyone has a fire extinguisher at home, it is also safer for you. If there is more than one fire extinguisher, use them simultaneously to put down the fire and not one after the other.

Valuable resources

Please also learn how to prevent fires and how to respond to a fire outbreak. These are just a few recommendations based on brochures of the Western Cape Government. It’s not a comprehensive list. You can find in-depth information on fire prevention here


The fire extinguisher was developed by Desania Govender and Yandisa Sojola. Design improvements and instruction by dooiy.

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Chris from dooiy

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