I know there’s been a little run on gasoline related questions here recently, but Mrs Vetch asked me a question at lunch today which I thought I could answer but on reflection I might have got wrong. She asked what would happen if you were to throw a lighted cigarette into a bucket of petrol (gasoline). I said you’d probably get singed eyebrows and a roaring fire. She then said what about if the bucket had been laying about for a while. To cut a long story short she was referring to a story she was reading ( see small extract below) ….and what did I think. I said I’d look it up on Straight Dope where the experts on everything hang out.
Well a search revealed threads about disposal of gasoline ( some a little heated, almost on fire even J ) but not quite answering the question.
So, here’s the extract:
“… I used to toss my cigarettes in a bucket of gas we kept in the service bay.”
…
“… That was how we put ‘em out. They’d hiss like you was tossin’ ‘em into a bucket o’water.”
…
“We kept gas in there to clean our hands on. Cuts grease, you know. …Well, if the bucket of gas was fresh, you had to wait awhile. If you saw any of that shimmerin’ of the fumes over it, like when you first pour it in there, or when you’re fillin’ your tank, well, you don’t want any open flame of any kind near that.”
“But once it sat and the, uh, shimmering fumes were gone?”
“Then we tossed our cigarette butts in there.” … “… it’s the fumes what burns.”
LaHaye, Tim and Jenkins, Jerry B., The Mark (Book 7 in the Left Behind series), Tyndale House Publishers, Inc., p109.
My question is, have these authors got this right, and if they have, how long would the bucket of gasoline take to “become safe”.
(And what would happen if you accidentally kicked the bucket- would it activate it again)
Only an idiot would toss a cig into a bucket of gas. I also don’t believe that mechanics would leave out a bucket to clean their hands with. Maybe put some in a spray bottle.
The story is full of shyte.
Once, when we were young and stupid, we were burning some gas in a metal box on the lawn. Some construction dudes then drove toward us, so I thought I’d just kick over this small box of gas so they couldn’t see I was dickin’ around.
Well, it because a 4-ft. high ball of fire right in front of me, and I’m glad I was totally unhurt. Scared the fuck outa me though.
The Myth-Buster guys were tossing cigaretts in a toilet that had different things poured in it and couldn’t get a fire started until they tried some black powder.
While in Kuwait about 14 years ago we burned trash in holes dug in the sand. Mostly poured diesel fuel and it and lit it with a match. One day a Staff Sergeant forgot and used gasoline. The “foomp” singed his hair and eyebrows. Aerated gas is bad. Fumes are bad.
Just a WAG, but it may be the case that since a cigarette butt isn’t really an open flame, but is just smoldering, it can be tossed through the gasoline vapors that are hovering on the surface of a bucket of gasoline without igniting them. If you held the smoldering cigarette in the fumes, the result might be very different.
A bucket that’s just been filled with gasoline might, indeed, have more concentrated vapors than a bucket that’s been sitting there for a while, since the act of pouring the gasoline into the bucket would stir things up quite a bit.
Once the butt hits the surface of the liquid, of course, it will go out, since liquid gasoline isn’t flammable - only the vapor will burn.
My grandparents lived in a house across the street from a small urban bus depot. Their block was the last one in town (Jersey City, NJ) before the next town began (Bayonne, NJ) so there was a small garage and refueling pumps surrounded by a large paved over area for buses to turn around.
My mother’s oldest brother was apparently at about age 12 or so walking across this area playing with a book of matches. Just lighting them and flicking them, as you do. There was apparently as its been described to me, a “bucket of water” lying on the ground which he decided to see if he could flick a match into.
The story picks up with a stranger from a block over knocking on my grandfather’s door with my uncle in his arms, and my grandfather apparently didn’t recognize him from the burns. He grew to adulthood and has no discernable scars.
I imagine much of this was exaggeration to keep me from playing with matches, or the amount of “water” was understated by my uncle but he would have had to have been thrown a good 20 feet across an overgrown area at the back of the depot before the next block was reached.
Regardless of the veracity of this story while it didn’t keep me from playing with matches entirely, I kept them away from gasoline.
Throwing a lighted cigarette into a bucket of gasoline is not a good idea because gasoline has a low flash point. The flash point is defined as the temperature at which a liquid emits flammable vapors. Its flash point is about 60 or 70 degrees Below Zero F.
However, if there is sufficient ventillation and vapors aren’t present, the cigarette will extinguish because of gasoline’s high ignition temperature. Its ignition temperature is actually several hundred degrees F. higher than that of newspaper.
That’s correct Headcoat. I remember a movie where James Spader throws a lighted cigarette onto a gasoline trail for an explosion. That’s Hollywood for ya.
Well, liquid gasoline doesn’t burn (or at least doesn’t burn well). It has to be vaporized. So, yeah, the vapors on top of the pool of gas would burn off, then it’d go out, I’d expect. Still, kinda risky, and I wouldn’t try it.
Assuming the flash point is reached and the cigarette ignites the vapors, would the temperature increase be enough to surpass the threshold for gasoline ignition and cause it to go off, too? What I’m getting at is whether it is more likely for the vapors to go off without actually igniting the gasoline than having both, gasoline and vapors, involved in the explosion?
You cannot light gasoline (liquid or fumes) with a smoldering fire; gasoline needs a spark or an open flame to ignite. I have seen the “cigarette into gasoline” trick done, it is true–the cigarette just goes out.
On a somewhat-related note, in bygone days when bales of cotton would catch fire, they were extinguished with kerosene because kerosene needs a spark just as gasoline does, and water will not soak into the center of the bales. Kerosene would soak all the way to the center, extinguish the fire, and the remaining cotton would be washed and still used.
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re: the trail of gasoline, yes, I believe that would work. Reason being: the end of the trail isn’t going to extinguish the end of the cigarette, but instead will be lit by it. I know I’ve done this with rubbing alcohol and rubber cement before and it worked, so I’m just extrapolating to gasoline.
[Grumpy Old Man Voice] Back when I was your age, we didn’t have SAFETY! We tossed cigarettes and matches into buckets of flammable stuff and watched what happened, and we liked it that way! And if you don’t know what a Grumpy Old Man is, tough luck! Back in my day we knew what grumpy old men were![/GOMV]
And that ain’t all: we used to bring fireworks to (grade) school and light them off during recess.
Wasn’t officially sanctioned, we got in trouble but didn’t even get sent home.
Now I think they call out a SWAT team if a kid even mentions burning or killing anything out loud.
(sigh) How sad.
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With a lit cigarette, the cigarette just goes out and sinks, without lighting the gasoline. Honest to God, I swear on my life. …With a lit match, the top of the gasoline does indeed catch fire and burn, and (if the bucket is metal!) the gasoline then stays lit like an oil lamp, until all the gasoline has evaporated and burned off.
???
Of course now gasoline is part alcohol, so there’s a slight chance this may no longer be correct–I have not tried it lately.
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okay. During fire training we tried jsut this experiment with a jar of gas, and then a pool of gas. Didn’t make a lick of difference with a cig sitting in the fumes for 1 minute or just dropping it. It has to do with the autoignition temperature of gas.
Er, are you saying that a lit match won’t ignite gasoline? Much less gasoline that’s been thrown on hot asphalt and given a chance to vaporize a bit? (Not trying to be fascetious–this is just counter to what I’ve heard and seen)