The restaurant where I work caught fire three weeks ago. The fire department’s report indicated it was caused by a hot towel in the bottom of the trash can. A coworker, who went to culinary school, says that hot towels interact with the black plastic of a trash can liner, causing gas buildup that can lead to combustion.
Can anyone explain how this works? The fire started about five or six hours after everyone left, and I just don’t get it.
the only thing I can think of is if there was some other flammable solvent or something in the can, which the towel heated to the point where something close by ignited the vapors. I don’t think a hot towel (assuming it was a “steamed” or damp towel) at 212°F is anywhere near hot enough to cause plastic to autoignite.
Far more likely is someone else dropped a butt in there and just isn’t fessing up.
Sometimes, kitchen towels catch on fire from sitting too close to the stove. They tend to stay lit for a long time if you don’t soak them in water. Its possible that a towel was slowly burning in the trash can for hours until the smoldering fibers found enough oxygen and another fuel source to start a larger fire.
I’ve actually witnessed a burned kitchen towel slowly shrink from a few red specks of fire, over the course of 30 minutes. My reaction was, “What happened to my towel? Oh, its still on fire!”
This can happen in you own home in a pile of clothes in the hamper or left in the dryer.
The residue of oil in the cloth gets hot and can ignite. This would be more likely in towels from a restaurant, washed or not. The employee’s explanation is bogus. Google spontaneous combustion for details.
If it’s the oily rags kind of spontaneous combustion, it’s more likely at, say, a mechanic’s shop.
The towel would have to be smoldering when it went into the trash or there was some other chemical involved such as linseed oil involved. I suppose it’s possible that plastic trash bags are made in such a way as to duplicate the effect but I’ve never heard of it.
This was a very rare problem a century ago - it’s almost unheard of now. Not every “oily rag” is a possible source of spontaneous combustion. Most of the Petroleum - based oils we use these days won’t undergo the exothermic oxidation required for spontaneous combustion; this requires something like Linseed oil, which used to be commonly used in paints, and is where the “oily rags” meme came from.
It may be unheard of, in the sense that it happens rarely or never, but it is nonetheless extremely well known as a safety issue in workshops. In my company, oily rags must be disposed of in a dedicated fireproof container for exactly this reason.
First hit :eek:
FWIW:
[ul]
[li]“Spontaneous combustion of cleaning rags blamed for Moncton, N.B., fire.” Canadian Press, The (February 12, 2010)[/li][li]Sheehan, Tim. “Tulare fire traced to soiled rags: Improper disposal led to spontaneous combustion, investigators say.” Fresno Bee, The (CA) (July 13, 2006)[/li][li]Napper, Robert. “Spontaneous combustion causes Anna Maria house fire.” Bradenton Herald, The (FL) (April 17, 2008)[/li][li]Holtzclaw, Mike. “BRIEF: ‘Spontaneous combustion’ started high school fire.” Daily Press (Newport News, VA) (August 07, 2007)[/li][li]Perez, Gayle. “CRIME BEAT: Rags may have started garage fire.” Pueblo Chieftain, The (CO) (May 13, 2010)[/li][/ul]
Just the first few examples I found searching EBSCOhost.
[hijack]Every rag container I have ever seen has the same wording printed on them. “Empty every night” Mkay, empty them into what? Another larger rag container that says “Empty every night”?
No one seems to have the answer to this question…
[/hijack]
Into a dumpster outside of the building, I’d guess. If that’s not possible, I’d at least move the container away from other combustibles and under a fire sprinkler head.
OK, here’s a really unlikely – but still possible – scenario that doesn’t involve OP’s acquaintance coming off as a complete moron:
The black plastic trash bag contains a plasticizer that becomes volatile when it’s heated – for example, when it’s in prolonged contact with a boiling hot wet towel. If a significant vapor pressure of said plasticizer builds up in the bottom of a trash can, then some other event (like a spark) could start a lovely fire.
Similar event: plastic trash bags, filled with H2 and air, often explode unexpectedly. Brief contact with other surfaces can create huge static charges on the PE surface which lasts for hours. You don’t need a bright “snap” spark; even a little crackling sound of glow-discharge can do it. For this reason the experienced halloween pranksters have to soak down their trash bags with soapy water. Heh!
Last month a physics demo staff member was almost injured when a van filled with H2 balloons all exploded at once. They went off upon opening the passenger door (so at least one balloon probably slid across the van ceiling.) Shattered window, singed eyebrows.
[Resists urge to perform Michael Caine impersonation…]
Come to think of it, I’ve seen this several times, too. In fact, as I was working saute, a corner of the towel caught on fire as I was jiggling a pan, which I failed to notice for about five minutes. This seems the simplest and most likely explanation.
For what it’s worth, I found one of our workers throwing the towel used to oil the grill into the garbage last night. Guess we found the culprit.
All the trash cans at my last place had a funnel shaped top that was supposed to prevent fires from burning for very long.
Yeah, fuel-air bombs using party balloons! I wonder if the shock compression heating does it? How big a gap can the explosion leap? Release a huge cloud of balloons, then fire off just one of them. Or, do the balloons need to be in contact, so flame-front has a chance of triggering the flame in the next balloon over?
If it can jump a fair gap between balloons, try making an acoustic lens from a CO2-filled balloon, so you can focus the shockwave beam and launch it across a much larger gap. Or use an old satellite TV dish with an exploding H2 O2 balloon near the focus …you could aim the distant focus at another hydrogen balloon? Or aim it at your skin. Bet it stings. Ooooo, low-tech “active denial” nonlethal weapon, no microwave kilowatt phasearray needed.