Spontaneous combustion–rubbish?

That old rubbish pile in your garage? Watch out. It may ignite.

That’s what they told me in elementary school. Only you can prevent the rubbish pile fire that will burn your house down to the ground. [Fast fact from Discover magazine’s “20 Things You Didn’t Know About Fire”: “…a typical house fire will double in size every minute.” (October 2011)]

It’s true. The chemical reactions in decomposing rubbish, defined here as piles of old newspapers and magazines, oily rags, and sawdust can generate enough heat to ignite. [Consider this, from an article in Popular Science magazine, circa 1946: “Such fires aren’t ‘black magic.'”]

Convicted by the rubbish pile risk, I got off the bus and went right to work on the mess under my bed. I don’t know if books and stuffed animals count as rubbish, but I don’t even think my flame retardant PJs would save me if my bed went up. Thank goodness I wasn’t storing any pistachios under my bed. [Another fast fact from Discover: “Pistachios have so much natural oil and are so prone to heat-generating fat decomposition that the International Maritime Dangerous Goods Code regards them as dangerous.”]

The phenomenon in rubbish piles (‘rubbish’ being a word I have now used more in this blog entry than cumulatively in my life to this point) is not unlike that of haystacks that, given the right temperature and moisture conditions, can spontaneously burst into flame. [Consider this, from William T.W. Woodward, of Washington State University: “Wet hay is more likely to lead to a spontaneous combustion fire than dry hay…High moisture hay stacks can have chemical reactions that build heat. Hay insulates, so the larger the haystack, the less cooling there is to offset the heat. When the internal temperature of hay rises above 130 degrees Fahrenheit (55 degrees C), a chemical reaction begins to produce flammable gas that can ignite if the temperature goes high enough.” The wetter the hay, the higher the risk of spontaneous combustion. The enigma that is fire, right?]

Spontaneous combustion: it’s just another hazard of living on earth, the only known planet with enough oxygen so that fire can burn.

Thanks, Discover. I did not know that.