Spontaneous Combustion Fire

[Kenomac]

I've been aware of the potential danger of spontaneous combustion for quite some time now, and taken special care with paint thinner and rags. As a former house painter and piano rebuilder, I've needed to dispose of these items safely on hundreds of occasions.

It's cold here in Massachusetts, so the other day I finally got started putting up the interior finish work in the house. Began by pre-staining some of it down in the basement Friday afternoon around 4:00 and left a couple of rags draped over a plastic trash can to dry out along with the trim pieces; the cotton rags were not soaked, just a little damp... being careful not to wad them up and just throw them in a trash can. Wasn't aware of the Cabot stain having a high linseed oil content, no label on the custom mixed can.

Woke up at 1:30am to a house filled with smoke and a plastic trash can on fire in the basement. Not fun, my wife and I put out the fire, but then it took two hours to get the nasty smelling smoke out of the house. Lucky, the fire sprinkler didn't go off, we caught it just in time.

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

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.

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.

The combustive nature of linseed oil rags may not happen outside in the middle of winter, but on a warm sunny summer day watch out! Certain cloth material that has smaller fibers such as cotton actually promotes combustion due to the small fluffy fibers. Anyone, I repeat ANYONE, using LINSEED OIL Soaked Rags should store them in a metal container with a lid soaking in water!

Note: I've lifted some of this post from another internet article and edited some of it. The fire was very real.

[MarkJ]

That happened to you? Or someone else's house?

[Kenomac]

Originally Posted by MarkJ

That happened to you? Or someone else's house?

Yes, it happened to us two nights ago. Quite the surprise.

[thinwater]

I've seen this in industrial settings with waste from resins (2-part).

Just 3 days ago a weld spark started a fire in some oil absorbent pads (unused) that took 4 hours to begin smoking. There wasn't much air in the sealed packaging, so it took a long time.

I always thought static build-up during a fuel transfer was a billion to one... until I led the accident investigation on one. It was diesel with a little gasoline added "for winter." It was very nearly fatal. Strangely, diesel/gasoline mixtures are more dangerous than gasoline in some ways.

When working with oil-based paints at home, I ALWAYS take the rags outside, every night. I sleep better. My Dad taught me that one 40 years ago.

So many possibility.

[MarkJ]

Absolutely bizarre.

Glad no one was hurt and your house wasnt destroyed.. It must have quite shaken up your wife... Next time she tells you to go paint the house you have a good excuse

[capngeo]

It's cold here in Massachusetts, so the other day I finally got started putting up the interior finish work in the house. Began by pre-staining some of it down in the basement Friday afternoon around 4:00 and left a couple of rags draped over a plastic trash can to dry out along with the trim pieces; the cotton rags were not soaked, just a little damp... being careful not to wad them up and just throw them in a trash can. Wasn't aware of the Cabot stain having a high linseed oil content, no label on the custom mixed can.

So now thick were the rags? If they were single layer, spontaneous combustion is almost impossible! If things were as described in the quote above, I'd be looking for a source of ignition other than described.

BTW, in the way of credentials, I am a retired firefighter, arson investigator, and avid user of the products you listed.

[Kenomac]

Originally Posted by capngeo

So now thick were the rags? If they were single layer, spontaneous combustion is almost impossible! If things were as described in the quote above, I'd be looking for a source of ignition other than described.

BTW, in the way of credentials, I am a retired firefighter, arson investigator, and avid user of the products you listed.

Absolutely no chance of a spark. I think a contributing factor was the type of rag, which was a surgical lap, much like a thin, sheer, cotton towel that allowed for the reaction to develop in small trapped air pockets. The rags which again were not soaked or saturated... just enough stain to color them, were draped single ply over the edge of the plastic waste container, one on each side.

Almost impossible... That's what I thought. But with the right set of circumstances... certainly possible.

Two hours prior to the fire, I did notice the smell of the stain permeating up through the floor, but didn't think anything of it. At this point, the oxidation was probably well under way with the rags heating up.

When we ran down into the basement and I approached the waste basket through the smoke, which was very thick, white in color, I couldn't believe how much heat was radiating from that basket. I quickly opened the basement door, grabbed the bucket and threw it outside. The fire was contained to just the bucket, but it did burst into flames as soon as I moved it. The heating boiler is over 20ft from where the fire started.

I've dealt with solvents and rags for many years, I guess I just set up the right set of circumstances to get the fire started. I'd always thought spontaneous combustion required the rags to be wadded up and in a somewhat enclosed environment. My situation was just the opposite. Possibly, the plastic waste basket acted as a chimney? Room temp was 58-62 degrees.

I wanted to share our experience because most folks working and living on boats will be using solvents at some point. You'll want to be sure to put those rags in water right away to eliminate the possibility of fire. The heck with thinking green... the only reason I was drying out the rags was because I didn't want to just throw them out into the snow, or put them in the outdoor trash can (fire risk). I was trying to render them environmentally safe to be discarded in the morning. BAD IDEA.

Our house was never in danger of burning down because we have fire sprinklers throughout, but this sure made a stinky mess of the place. Finally today, the burnt plastic smell is starting to diminish.

[daddle]

Epoxy in a cup burn nice too!

[Kettlewell]

From your description of the situation I am very surprised. I grew up in a household with an artist working in oils so we had endless linseed oil soaked rags lying around continuously for decades. I can just imagine the smell now. The walls of my current house are covered with some of those numerous oil paintings. I also worked in a boatyard and on wooden boats for many years, and never encountered such a thing. Yes, we didn't leave wadded up rags in piles, but a rag left out for drying purposes never went up in flames.

[Blue Stocking]

Any vegetable oil, linseed, flaxseed,etc, under the right conditions with a natural fibre, such as cotton, is subject to spontaneous heating.
Its in the same "speed of combustion" category as explosions in corn and flour silos.
Basic "fire triangle" and "fire tetrahedron" stuff for firefighters,
( 17yrs in, finished as Captain in 1980.)

[Nicholson58]

Originally Posted by Kenomac

I've been aware of the potential danger of spontaneous combustion for quite some time now, and taken special care with paint thinner and rags. As a former house painter and piano rebuilder, I've needed to dispose of these items safely on hundreds of occasions.

It's cold here in Massachusetts, so the other day I finally got started putting up the interior finish work in the house. Began by pre-staining some of it down in the basement Friday afternoon around 4:00 and left a couple of rags draped over a plastic trash can to dry out along with the trim pieces; the cotton rags were not soaked, just a little damp... being careful not to wad them up and just throw them in a trash can. Wasn't aware of the Cabot stain having a high linseed oil content, no label on the custom mixed can.

Woke up at 1:30am to a house filled with smoke and a plastic trash can on fire in the basement. Not fun, my wife and I put out the fire, but then it took two hours to get the nasty smelling smoke out of the house. Lucky, the fire sprinkler didn't go off, we caught it just in time.

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

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.

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.

The combustive nature of linseed oil rags may not happen outside in the middle of winter, but on a warm sunny summer day watch out! Certain cloth material that has smaller fibers such as cotton actually promotes combustion due to the small fluffy fibers. Anyone, I repeat ANYONE, using LINSEED OIL Soaked Rags should store them in a metal container with a lid soaking in water!

Note: I've lifted some of this post from another internet article and edited some of it. The fire was very real.

Spontaneous combustion can happen in many different oil soaked situations with different oils and media. I was first aware of it in one of our tank farms when the oil soaked fibergalss insulation burst into flames. This occurs when a media catalizes the reaction (burn) at much lower than ordinary ingintion temperatures. Different media and oil combinations can work together so that combustion takes place at very low temperatures. Sometimes all you need is for them to be in a confined spot with a sunbeam or other hot source nearby. Consider this also a possibility with diesel.

Glad you are OK.

[Blue Stocking]

Originally Posted by Nicholson58

Spontaneous combustion can happen in many different oil soaked situations with different oils and media. I was first aware of it in one of our tank farms when the oil soaked fibergalss insulation burst into flames. This occurs when a media catalizes the reaction (burn) at much lower than ordinary ingintion temperatures. Different media and oil combinations can work together so that combustion takes place at very low temperatures. Sometimes all you need is for them to be in a confined spot with a sunbeam or other hot source nearby. Consider this also a possibility with diesel.

Glad you are OK.

+1.

Whereas petroleum based liquids get into factors such as flammability range, auto-ignition temperature, and flash point, these can be significantly different when dealing with natural oils and fibres.

[Andrew Troup]

Yes, I had a similar situation with a few thickish oily rags, not wadded up, but in my case inside a metal rubbish bin with a lid. There was not enough oxygen to sustain full-on combustion, mercifully, but it still got the lid hot enough to melt a polythene shopping bag filled with rubbish sitting on top.

[hpeer]

Check out this story.

One Meridian Plaza - Wikipedia, the free encyclopedia

[donradcliffe]

I stained a new door last month, and noticed that the directions on the stain were to put the waste rags in a metal container with a lid. I figured this was just lawyer language and laid the staining rags single-thickness on a plastic bucket. I had no problems, because in a single layer the surface to volume ratio is too big for the temperature to be a problem.

My experience with epoxy is similar--a cup with 1 inch of epoxy will start to smoke, but 1/8 inch will be fine.

Not a fire expert, but I do have a couple of degrees in heat and mass transfer.