How often do you actually use your fire extinguisher? Hopefully never. So how do you know it'll function in an emergency? Oh, sure, there's a pressure gauge—but are you really willing to trust your home and the lives of your children to some cheap imported piece of junk? Won't you feel like a dope when you go to grab the extinguisher, and find that the contents had leaked slowly over the years, but a rusty valve spring had prevented the gauge from indicating that fact?

Really, the only way to be sure is to have a look inside. We could make the extinguisher transparent, but it wouldn't be obvious exactly what a full extinguisher was supposed to look like as opposed to an empty one. Instead, we make the extinguisher *translucent*, like an egg. And much like the process of “candling” an egg, we can shine a bright light through the extinguisher to check its contents.

At the base of the extinguisher is a built-in lantern. When switched on, the light shines through the extinguisher. A molded plastic reference window near the bottom (designed to have similar optical properties to a properly charged extinguisher) indicates the color your extinguisher should be. If your extinguisher isn't the right color, throw it away and buy a new one.

It's better than letting your kids die in a fire caused by some idiot forgetting to put out a candle.
-- ytk, Jun 18 2014

(+) for transparency.
-- 2 fries shy of a happy meal, Jun 18 2014


Most fire extinguishers are designed to be re-charged after a discharge. I would consider a leak to be a slow discharge. If you discover that, then repairing the thing that leaked, and getting a full re- charge, should be cheaper than buying a new one.
-- Vernon, Jun 18 2014


All very well, but it would probably be easier just to check the weight.
-- Loris, Jun 18 2014


Ah, but this is self-contained. I don't have a single scale in my house suitable for weighing a fire extinguisher to the degree of accuracy necessary to determine whether it's full or not. It's too heavy for my kitchen scale, and my bathroom scale isn't accurate enough. The beauty of this idea is that no scale is necessary.
-- ytk, Jun 18 2014


+ This would be great for me. I have 2 fire extinguishers, yet have never used one in my life. Now that you've mentioned this, I think I should go get some new ones. Thanks.
-- xandram, Jun 18 2014



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