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Linseed Oil - Spontaneous Combustion is a REAL danger for homeowners!

I had my doubts about spontaneous combustion... till my readers spoke out!  Spontaneous combustion, more common in horror movies than in real life, refers to the phenomenon that occurs when an object suddenly bursts into flame without obvious cause.  No match, no sparks, no lightning, no electrical short or smoking cigarette... nothing!

What causes it?  With linseed oil and other oils used to finish wood, including some exterior deck sealers and wood stains, heat is generated during the drying process.  This is because these oils do not dry like paint (through the evaporation of a solvent or water).  Instead, they dry through the same process that generates fire... oxidation.

Despite the testimonials (read "horror stories") about spontaneous combustion at the end of this article, the fact is it's a difficult phenomenon to reproduce.  I've tried to cause it a number of times and have never been able to.  But, then again, I believe in lots of things I haven't personally seen.  I think that's known as "faith".  And trust me... spontaneous combustion is real!

Oxidation generates lots of heat... and can cause fires!

And that's the key!  Burning is rapid oxidation.  For spontaneous combustion to occur, enough heat must accumulate so fire can start.  You would never see a piece of furniture spontaneously combust because the oil oxidizes in open air so the surface never even gets warm to the touch!  But a pile of oil-soaked rags can...

A pile of oil-soaked rags can get smokin' hot...

In every case of spontaneous combustion of drying oils that I have found, the cause has been a bunch of oil soaked rags.  It seems that, as the oil oxidizes, the rags act as an insulator, allowing the oxidizing oil  to become hot enough to cause the cloth to smoke and eventually ignite.  The bigger the pile, the greater the possible heat and the greater the risk.

Room temperature is also a factor.  The warmer it is, the quicker the rags can reach ignition temperature.

Let my readers tell you their scary stories...

This is your brain on linseed oil...

Well, that's it.  If you ever had any doubts of the danger of spontaneous combustion with linseed oil, consider them vanquished.  Like me, none of these readers had a clue, and fortunately none of them lost their  lives.

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