# Lighting vs. Oil Tanks
**URL:** https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193
**Category:** Factual Questions
**Created:** [March 19, 2012, 3:19am UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193 "2012-03-19T03:19:46Z")
**Posts on this page:** 10
**Page:** 1
### Author:  [@ClintO](https://boards.straightdope.com/u/ClintO)
#### Post date: [March 19, 2012, 3:19am UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/1 "2012-03-19T03:19:46Z")
Say I’m sitting on an oil location with 1000 bbls of oil on location. What is the explosive nature of lighting hitting an oil tank? How far away would one want to be away in the off chance it was hit? What would it be comparable to as far TNT explosiveness?
Sitting on location in a lighting storm… :eek:
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### Author:  [@TriPolar](https://boards.straightdope.com/u/TriPolar)
#### Post date: [March 19, 2012, 3:23am UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/2 "2012-03-19T03:23:10Z")
I turn lights on all the time around different quantities of oil. No explosions so far.
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### Author:  [@engineer\_comp\_geek](https://boards.straightdope.com/u/engineer_comp_geek)
#### Post date: [March 19, 2012, 3:30am UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/3 "2012-03-19T03:30:31Z")
Yes I would expect lighting to be fairly safe around oil tanks.
Lightning on the other hand is a bit more of a concern, but I wouldn’t worry too much about it. Lightning does cause oil tank fires on occasion, but you won’t get a really big earth shattering ka-boom simply because you don’t have enough oxygen for combustion present.
Similarly, if you drop a match in a bucket of gasoline, what usually happens is just that the match goes out. You probably don’t want to try that one at home though. If you get the right concentration of gasoline fumes and air above the bucket, things can get really interesting when you drop the match through that.
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### Author:  [@ClintO](https://boards.straightdope.com/u/ClintO)
#### Post date: [March 19, 2012, 3:33am UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/4 "2012-03-19T03:33:56Z")
lighting … is in fact not the same as lightning… holy… i blame the storm
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### Author:  [@newme](https://boards.straightdope.com/u/newme)
#### Post date: [March 19, 2012, 4:35am UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/5 "2012-03-19T04:35:05Z")
From [Wikipedia on TNT:](http://en.wikipedia.org/wiki/Trinitrotoluene#Energy_content)
> [@](#):
>
> TNT contains 4.184 megajoules per kilogram… gasoline contains 47.2 megajoules per kilogram (though gasoline requires an oxidant, so an optimized gasoline and O2 mixture contains 10.4 megajoules per kilogram)
So gasoline and oil are even more energy dense than TNT. Why, I bet if you could find a way to explode a gallon of gasoline in may, many tiny controlled explosions, you could propel an automobile over 30 miles at 70 miles per hour…
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### Author:  [@Sigene](https://boards.straightdope.com/u/Sigene)
#### Post date: [March 19, 2012, 12:16pm UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/6 "2012-03-19T12:16:08Z")
> [@engineer\_comp\_geek](#):
>
> Similarly, if you drop a match in a bucket of gasoline, what usually happens is just that the match goes out. You probably don’t want to try that one at home though. If you get the right concentration of gasoline fumes and air above the bucket, things can get really interesting when you drop the match through that.
I know you said you don’t want to try this at home, but it is absolutely incorrect and dangerous to think that when dropping a match in a bucket of gasoline the match will **USUALLY** go out. It won’t. It will light the bucket on fire as expected. To suggest otherwise is dangerous and likely to produce Darwin award winners.
I don’t dispute the other part of your post, but to suggest the match \*usually \*going out is wrong.
I suspect your thought comes from the idea that a lit cigarrette in gasoline will go out. This I’ve done myself (though I did it under controlled conditions)
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### Author:  [@Machine\_Elf](https://boards.straightdope.com/u/Machine_Elf)
#### Post date: [March 19, 2012, 12:30pm UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/7 "2012-03-19T12:30:49Z")
Oil is flammable, but it’s not exactly explosive - which is to say it’ll burn if you take the time to get it started, but a little spark won’t do it.
If it _does_ get started, it will burn very well, and for a long time. And if you can stir it up to mix it with air, you can get a very large, very vigorous fire. Consider [this event](http://www.youtube.com/watch?v=RSUNSEIU7es) in Texas about 20 years ago. You know how home safety folks say to never put out a grease fire in your kitchen with water, because the water goes to the bottom of the pan, boils, and spews hot flaming grease all over your kitchen? That’s pretty much what happened here. Oil tank fire, and the FD was blasting water at it; water settled to the bottom of the tank, and once it started boiling (this took a while), it spewed hot flaming oil up in the air resulting in a _massive_ fireball. People in attendance received second and third degree burns - not from direct contact with the fireball, but just from the radiant heat, even though they were at a pretty large distance from it.
Re: lightning strikes, oil storage tanks are likely protected by lightning rods, which provide a safe path for lightning to reach the ground. Bottom line? Lightning is unlikely to ignite an oil storage fire, and if it does, the fire will develop slowly enough so that you’ll have time to escape. Just make sure you take your valuables with you.
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### Author:  [@ClintO](https://boards.straightdope.com/u/ClintO)
#### Post date: [March 19, 2012, 12:52pm UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/8 "2012-03-19T12:52:03Z")
Turns out last night a salt water disposal was struck by lightning last night and burned to the ground. They have limited oil on location, which is skimmed off the top of the water hauled to the location, but the fire was visible from 10 miles away. So they do get struck by lightning and catch on fire, but might not blow up like I thought.
One would think 1000 bbls at 42 gallons a barrel would make a fire one wouldn’t want to be within a mile of. My 200 yards distance might not work out. Going for a drive next time.🙂
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### Author:  [@Quercus](https://boards.straightdope.com/u/Quercus)
#### Post date: [March 19, 2012, 12:58pm UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/9 "2012-03-19T12:58:21Z")
> [@newme](#):
>
> So gasoline and oil are even more energy dense than TNT. Why, I bet if you could find a way to explode a gallon of gasoline in may, many tiny controlled explosions, you could propel an automobile over 30 miles at 70 miles per hour…
Right, TNT has its own oxidizer taking up mass, and oil doesn’t. So TNT is less energy dense, but can explode all by itself, whereas to burn oil, you need to add oxygen. If you can add oxygen to a bunch of oil (by turning the oil into a mist of oil/air mixture), you do indeed get a boom. If it’s in the cylinder of a engine, a small controlled boom. Or you can make a big boom: [Thermobaric weapon - Wikipedia](http://en.wikipedia.org/wiki/Fuel-air_explosive).
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### Author:  [@LonghornDave](https://boards.straightdope.com/u/LonghornDave)
#### Post date: [March 20, 2012, 3:31pm UTC](https://boards.straightdope.com/t/lighting-vs-oil-tanks/616193/10 "2012-03-20T15:31:30Z")
> [@ClintO](#):
>
> One would think 1000 bbls at 42 gallons a barrel would make a fire one wouldn’t want to be within a mile of. My 200 yards distance might not work out. Going for a drive next time.🙂
The bigger tank batteries would likely have lightning rods, so you are typically talking about the smaller ones. Having said that, 1,000 bbls wouldn’t be out of the question. We had a lightning strike in Central Texas affecting a tank battery with about 600 bbls in it last year. There wasn’t really any affects outside of the berm that surrounded the battery. The fire crews just let it burn off. I think the biggest issue in staying at a distance was the gas emissions.