Petrol lit with a cigarette? Only in the movies

[snopes]

From Hitchcock's The Birds to The Usual Suspects, it has been one of the staple cliches of Hollywood: the cigarette butt tumbling in slow motion into a pool of petrol unleashing a conflagration.

But if you find yourself tied up and doused in petrol don't worry if all your assailant has is a lighted cigarette: scientists have proved you won't end up as a human fireball.

http://film.guardian.co.uk/print/0,,...8-3156,00.html

[JoeBentley]

I remember Mythbusters debunking this one some time ago.

But Hollywood has always played fast and loose with gasoline. It's next to impossible to get a car to explode by shooting it as well.

[Troberg]

But if you find yourself tied up and doused in petrol don't worry if all your assailant has is a lighted cigarette: scientists have proved you won't end up as a human fireball.

Petrol has a very narrow air/petrol ratio on which it will burn, but it does exist. Don't rely on not being in that ratio. The liquid itself is safe, but you have no idea if the vapours around it will ignite, and if they do, it becomes a big fireball.

Insulting Stupid Movie Physics had also experimented with this and they found that no matter how hard they tried, they could not get the gas to ignite with a cigarette.

[Troberg]

Insulting Stupid Movie Physics had also experimented with this and they found that no matter how hard they tried, they could not get the gas to ignite with a cigarette.

In liquid form, it's about as safe as water. It's the vapour that can be ignited, and as petrol is so prone to give off vapour, even the liquid form needs to be respected.

Petrol is nasty and unpredictable and prone to go boom, and if you are going to experiment with burning liquids, etanol or metanol is much safer.

But static electricity WILL do the trick. So if you want the fireball, get in and out of your car several times and then touch the gas nozzle. Eventually, you will get your explosion.


"The golden light above you shows me where you're from..."

[Not_Done_Living]

My old shop class teacher used to put a pile of sawdust on a table and throw lit matches into it.

It would never ignite, the matches would burn out before the sawdust caught.

Of course, he was also missing pieces of several fingers, so he probably wasn't the smartest of the staff....

[Silas Sparkhammer]

Originally Posted by Not_Done_Living

My old shop class teacher used to put a pile of sawdust on a table and throw lit matches into it.

It would never ignite, the matches would burn out before the sawdust caught.

Of course, he was also missing pieces of several fingers, so he probably wasn't the smartest of the staff....

re his fingers, sad grin...

re sawdust, try it with very fine wood shavings ("excelsior") as opposed to sawdust.

When I was young, I used to play dumb games with explosives and inflammables: yes, you can flip lit matches into a pool of gasoline, and, sometimes, the match just goes out with a hiss. And sometimes, the pool of gas goes up in flames.

At the risk of a painfully obvious joke, anyone who would depend on this effect would likely be the individual opposite of your snopes login name!

Silas

[jimmy101_again]

Originally Posted by Silas Sparkhammer

... When I was young, I used to play dumb games with explosives and inflammables ...

{Dr. Nick Voice} Inflammable means flammable? Who knew?".{/Dr. Nick voice}

[Bored and Dangerous]

My SO had his eyebrows singed off during latrine duty in Saudi Arabia by said method. He had to light the barrels of waste and watch them burn...what a nice job. It was a windy day one day and he decided, quite stupidly, to light the match on the inside of a barrel after pouring "mogas" and diesel over the waste because he couldn't strike it anywhere else. The vapors caught, whooshed up his arms and to his eyebrows. He didn't have hair on his arms or face (except for mild stubble) for a few weeks after. He was quite embarrassed, to say the least.

Originally Posted by JoeBentley

But Hollywood has always played fast and loose with gasoline. It's next to impossible to get a car to explode by shooting it as well.

It depends. I was told by a close friend that his BIL (a local cop in my hometown) used tracers for that purpose. I strongly suspect they would work, but only because they provided an existing heat source. OTOH, it is still possible that there isn't enough oxygen in the mix to ignite the gasoline in the tank, so who knows?

[Silas Sparkhammer]

Originally Posted by Bored and Dangerous

My SO had his eyebrows singed off during latrine duty in Saudi Arabia by said method. He had to light the barrels of waste and watch them burn...what a nice job. It was a windy day one day and he decided, quite stupidly, to light the match on the inside of a barrel after pouring "mogas" and diesel over the waste because he couldn't strike it anywhere else. The vapors caught, whooshed up his arms and to his eyebrows. He didn't have hair on his arms or face (except for mild stubble) for a few weeks after. He was quite embarrassed, to say the least.

One of my co-workers had scars on his face from when he tried to "jump start" the barbecue using gasoline.

(Could be worse; a friend of mine has partial hearing loss in one ear from playing "basement bomber" with blasting caps. Also some slight permanent damage to two fingers.)

(Then there's a guy, the papa of another friend, who cut off a finger while using a bandsaw. A few months later, he cut off another finger in almost exactly the same way.)

Silas ("Low Slearners!")

Originally Posted by Bassist

It depends. I was told by a close friend that his BIL (a local cop in my hometown) used tracers for that purpose. I strongly suspect they would work, but only because they provided an existing heat source. OTOH, it is still possible that there isn't enough oxygen in the mix to ignite the gasoline in the tank, so who knows?

Mythbusters redid the show with tracer rounds and the gas tank did catch on fire.

Originally Posted by JoeBentley

It's next to impossible to get a car to explode by shooting it as well.

I disagree with that. It's not next to impossible. With the right gun you can have a pretty good explosion. One that shoots enough rounds to have a high probability it hits the right spots will have a nice explosion. I've seen it done.

But I agree that single shot guns ARE next to impossible.