Q: So, I bashfully admit that I started a small kitchen fire a few weeks back. I’m one lucky guy since there was no real damage done — just a scorched pan. I was left with an extra crispy lunch, jittered nerves and a lesson learned: Never, ever cook bacon while totally distracted by a televised college basketball game.

I was also left wondering if there are any effective, eco-friendly alternatives to standard fire extinguishers out there. What exactly is in those typical 5-pound household extinguishers anyway? I’m guessing some kind of chemical agent but I’ve never been quite sure. Whatever came out of mine was messy and mysterious. Do you any leads on how to be safe and prepared without dousing my home with flame-smothering chems?


Not burning down the house,  

Glen – Wichita, Kan.

Hey Glen,

Phew! Glad everything turned out OK and the damage wasn’t too bad. Do me a favor, okay? Please be extra careful while simultaneously cooking and watching NCAA playoffs.

I’m not exactly sure what kind of fire extinguisher you used to remedy your flamin’ bacon, but chances are it was either a multipurpose, dry chemical extinguisher used for Class A (ordinary solid combustibles like paper, plastic, cardboard), Class B (flammable liquids like gas and grease) and Class C (electrical) fires or a regular dry chemical extinguisher used for Class B and Class C fires.

The good news? Those mysterious chemical agents in both types of extinguishers are nothing more than sodium bicarbonate (common baking soda!) or ammonium phosphate pressured by nitrogen. Both are nontoxic so there’s no need to call in the Hazmat team after putting out a small kitchen fire. However, the ammonium phosphate, used in multipurpose fire extinguishers, can be more corrosive than sodium bicarbonate and requires immediate cleanup … it’s not necessarily dangerous to your health or the planet but can potentially damage whatever it comes in contact with. For this reason, it’s not recommended for use on airplanes and on electronics.  

If you’re looking to avoid the mess and possible damage left by both ABC and BC type fire extinguishers, you may want to invest in a carbon dioxide, yes, carbon dioxide, fire extinguisher. Liquid CO2 fire extinguishers are preferred for Class B and C fires but do not work on Class A fires where flammable solids are involved.

And then there’s pressurized water fire extinguishers. Although these extinguishers may seem the most simple and eco-friendly, they’re appropriate only for Class A fires. Water can be dangerous when treating Class B fires since it can cause the flames to spread. When used against Class C fires, water becomes conductive and can actually lead to electrical shock. So if your first inkling is to douse any kind of fire with straight-up water, think again.

My advice? Go with a multipurpose, ABC extinguisher. It may be the messiest and potentially the most damaging choice of the lot but it gets the job done and you won’t have to juggle multiple extinguishers meant for specific types of fires. I also recommend having that miraculous, versatile white stuff, baking soda, around in the kitchen to put out small grease fires. If you’re keeping a green home, you're already using the mighty BS for a gazillion other uses, so why not have a dedicated box for cooking fires? And it goes without saying Glen, make sure that the smoke detectors in your home are functional and if things get out of control, please get out and then call the fire department. Thanks for writing in and be safe.

— Matt

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Matt Hickman ( @mattyhick ) writes about design, architecture and the intersection between the natural world and the built environment.

Is there an eco-friendly way to extinguish a small fire?
It turns out that what's in those kitchen fire extinguishers isn't so nasty after all. Matt Hickman's got the scoop.