Is Smoking While Pumping Gas a Real Explosion Risk?

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The discussion centers around the dangers of smoking while refueling at gas stations, particularly the risk of igniting gasoline. Participants debate whether a lit cigarette can cause a catastrophic explosion, noting that while it is theoretically possible, the actual risk is low due to the ignition temperatures of gasoline and the typical temperature of a cigarette. They reference studies and experiments, including those by Mythbusters, which demonstrate that it is challenging to ignite gasoline with a cigarette, especially in open air. The conversation also touches on the potential for static electricity to ignite gasoline vapors, with statistics indicating that static discharge incidents are more common than fires caused by smoking. Participants emphasize the importance of safety at gas stations, advising caution around smoking and static electricity. Overall, while smoking at gas pumps is illegal and considered dangerous, the likelihood of a serious incident occurring is deemed low, although still not advisable.
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Last night I was coming out of the convenience store and saw this redneck pumping gasoline with a lit cigarette in his mouth. I'm pretty sure this is against the law here. Is it very likely to cause a catastrophic explosion? Or is it just the severity of the possible damage that makes it a bad idea, even if it is unlikely?
 
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I say, "Stand at a safe distance and watch Darwin In Action!"
 
I read a description of the burns and other injuries (in my JEMS magazine) sustained by a man who was leaned over filling a gas can at the pump, while smoking. Apparently a hot ash fell into the can, and it exploded. He ended up with burns over most of his body, as well as lung problems from being put out with a fire extinguisher. He died a day or two later.

Yeah, stay well back.
 
berkeman said:
problems from being put out with a fire extinguisher. He died a day or two later.

Thats a broad meaning of "being put out".
 
It's possible to ignite gasoline with a cigarette, but just barely.

http://mythbustersresults.com/special7

Ignition temperature for various fluids

Gasoline: 800 deg
Propane: 871 deg
Flour: 748 deg
Acetylene gas: 571 deg
60 Octane gas: 536 deg
Paper: 446 deg
#1 Fuel oil: 444 deg
Wood: 392 deg

Cigarette temperature when inhaling: about 550 deg

There's also a small possibility of vapors accumulating and igniting (vapors have a lower ignition temperature). While you could accumulate vapors in a gas can, it's very unlikely that enough vapors would accumulate in an open air gas station while refueling your car - especially if there's any kind of breeze.

It's not particularly easy to drop a lit cigarette into your gas tank nowadays, especially if you've got the nozzle stuck in the refueling tube, so, while it's possible the vapors in your car's gas tank could be ignited, the odds aren't very good.
 
Chi Meson said:
I say, "Stand at a safe distance and watch Darwin In Action!"

:smile:
 
BobG said:
It's possible to ignite gasoline with a cigarette, but just barely.

http://mythbustersresults.com/special7

Ignition temperature for various fluids

Gasoline: 800 deg
Propane: 871 deg
Flour: 748 deg
Acetylene gas: 571 deg
60 Octane gas: 536 deg
Paper: 446 deg
#1 Fuel oil: 444 deg
Wood: 392 deg

Cigarette temperature when inhaling: about 550 deg

There's also a small possibility of vapors accumulating and igniting (vapors have a lower ignition temperature). While you could accumulate vapors in a gas can, it's very unlikely that enough vapors would accumulate in an open air gas station while refueling your car - especially if there's any kind of breeze.

It's not particularly easy to drop a lit cigarette into your gas tank nowadays, especially if you've got the nozzle stuck in the refueling tube, so, while it's possible the vapors in your car's gas tank could be ignited, the odds aren't very good.

Beat me to it! Bah... That was a good episode. One of the guys literally knelt down on the ground with this cigarette in his mouth puffing on it so it gets hot right over top of a puddle of gasoline and it still wouldn't light.

I was waiting to watch his face catch on fire, but it never happened...
 
IIRC, didn't he drop the cigarette into a puddle of gasoline and it extinguished the cigarette?

Of course with my luck, my static cling will blow up the entire station.
 
I've put out many cigarettes in gasoline to mess with friends. Never ignited the gas.

I wouldn't do it in a hot arid region though, assuming the fumes are more volatile.
 
  • #10
The only trouble is when a cigarette ejects a 'spark' on that rare occasion as I've seen them do---THAT would ignite fumes.
 
  • #11
If you're driving behind another vehicle, you can usually tell which side their gas filler tube is located. It's almost always on the opposite side of the tailpipe to reduce the chance of pouring gasoline on a hot exhaust system.

Actually, it's on the opposite side of the muffler, so you can get fooled by dual exhaust or by mufflers that run laterally (such as the Dodge Dynasty).

Realistically, your exhaust system should be less than 600 deg that far back along the exhaust, but the exhaust system on a malfunctioning car can get hotter - especially with a catalytic converter.
 
  • #12
BobG said:
It's possible to ignite gasoline with a cigarette, but just barely.

http://mythbustersresults.com/special7

Ignition temperature for various fluids

Gasoline: 800 deg
Propane: 871 deg
Flour: 748 deg
Acetylene gas: 571 deg
60 Octane gas: 536 deg
Paper: 446 deg
#1 Fuel oil: 444 deg
Wood: 392 deg

Cigarette temperature when inhaling: about 550 deg

There's also a small possibility of vapors accumulating and igniting (vapors have a lower ignition temperature). While you could accumulate vapors in a gas can, it's very unlikely that enough vapors would accumulate in an open air gas station while refueling your car - especially if there's any kind of breeze.

It's not particularly easy to drop a lit cigarette into your gas tank nowadays, especially if you've got the nozzle stuck in the refueling tube, so, while it's possible the vapors in your car's gas tank could be ignited, the odds aren't very good.

Thanks for this info. I figured there was a lot of mythologizing about gasoline and cigarettes on account of what you see at the movies, not to mention propaganda from anti-smoking zealots. But still, it seems pretty stupid to smoke at the pump. I don't doubt that some of the horror stories of accidents caused this way are true. Even if it is unlikely.

I wonder what the burning temperature of a wood kitchen match is. I know from experience that it is no trouble at all to light a little cupcake/pie tin full of gasoline with one of those "strike anywhere" matches. But then, maybe I was really igniting the fumes that accumulated over the liquid.

Chi Meson said:
I say, "Stand at a safe distance and watch Darwin In Action!"

Heh. Yeah, that's exactly what popped in my mind. Of course, it doesn't work that way. From a purely evolutionary point of view, that gentleman is doing much better than I am. He probably has a number of children, some of whom will survive to reproducing age. :smile:
 
  • #13
BobG said:
It's possible to ignite gasoline with a cigarette, but just barely.

http://mythbustersresults.com/special7

Ignition temperature for various fluids

Gasoline: 800 deg
Propane: 871 deg
Flour: 748 deg
Acetylene gas: 571 deg
60 Octane gas: 536 deg
Paper: 446 deg
#1 Fuel oil: 444 deg
Wood: 392 deg

Cigarette temperature when inhaling: about 550 deg

There's also a small possibility of vapors accumulating and igniting (vapors have a lower ignition temperature). While you could accumulate vapors in a gas can, it's very unlikely that enough vapors would accumulate in an open air gas station while refueling your car - especially if there's any kind of breeze.

It's not particularly easy to drop a lit cigarette into your gas tank nowadays, especially if you've got the nozzle stuck in the refueling tube, so, while it's possible the vapors in your car's gas tank could be ignited, the odds aren't very good.

Nowadays the gas stations sell gasoline with 10% ethanol in them. I wonder how much lower that brings the flash point down, considering flash point of ETOH is 55 deg F
 
  • #14
There have been a number of documented cases of gasoline fires started by static discharge, so I'd give any smoking gas-pumpers a wide berth.
 
  • #15
turbo-1 said:
There have been a number of documented cases of gasoline fires started by static discharge, so I'd give any smoking gas-pumpers a wide berth.

When you say "a number," what do you mean? Because 1 would be a number. I've heard of this happening 2 or 3 times in the past 15 years or so. It seems pretty hard to accomplish.

I don't know if they still do this, but at one point, gas stations used to have instructions to turn your cell phone off, because the electronics inside could ignite the fumes. I have no idea what they based that on, though.
 
  • #16
It's hard to say a static discharge fire is more likely when smoking at a gas pump is illegal. Every time you put the nozzle in the filler tank, there's a chance of static discharge while it's rare for a person to smoke while filling their gas tank.

Still, having a static discharge right at the area where fuel vapors would be escaping would seem to be a lot more likely to result in a fire than smoking in general. You'd have to put the cigarette near the area where the vapors were.

The cell phone warnings are almost certainly bogus, though.
 
  • #17
Jack21222 said:
When you say "a number," what do you mean? Because 1 would be a number. I've heard of this happening 2 or 3 times in the past 15 years or so. It seems pretty hard to accomplish.

I don't know if they still do this, but at one point, gas stations used to have instructions to turn your cell phone off, because the electronics inside could ignite the fumes. I have no idea what they based that on, though.
In this case "a number" as documented by the petroleum industry is at least 150, backed up by video-recordings at gas stations.

I once had a boss that was a congenital liar. He would lie when the truth would serve him better. He once told me to tell a lady that "a number" of people had informed me of her husband's death when in fact it was one insider who knew of the man's collection of CW swords. I refused to lie to her and he threatened to fire me on the spot. I refused again, and he fumed and stormed off. I made the lying jerk millions of dollars and turned his business around, and he had the temerity to demand that I act as unethically as he did, day-in, and day-out.
 
  • #18
turbo-1 said:
In this case "a number" as documented by the petroleum industry is at least 150, backed up by video-recordings at gas stations.

I once had a boss that was a congenital liar. He would lie when the truth would serve him better. He once told me to tell a lady that "a number" of people had informed me of her husband's death when in fact it was one insider who knew of the man's collection of CW swords. I refused to lie to her and he threatened to fire me on the spot. I refused again, and he fumed and stormed off. I made the lying jerk millions of dollars and turned his business around, and he had the temerity to demand that I act as unethically as he did, day-in, and day-out.

150 over what time period? I don't doubt the number, I'm just trying to figure out exactly how common it is. Is this 150 per year, or 150 over the last 30 years, or something in between?
 
  • #19
Jack21222 said:
150 over what time period? I don't doubt the number, I'm just trying to figure out exactly how common it is. Is this 150 per year, or 150 over the last 30 years, or something in between?
Since 1999, I believe. Google it.
 
  • #20
turbo-1 said:
Since 1999, I believe. Google it.

Trying to google it now. Came up with http://www.snopes.com/autos/hazards/static.asp so far, which references a PEI study that says "to date" there have been 150, but doesn't list a starting time.

The link to the PEI study from snopes is a dead link.

Through a little more googling PEI, I came up with a PDF file: http://www.pei.org/Portals/0/resources/documents/Refueling%20Fire%20Incidents.pdf

This states there have been 173 reported from 1992 to 2008, which is a span of 16 years.

Averaging that out, appears that there are about 17 gasoline fires per year. The PEI estimates that Americans refill their vehicles 11 to 12 billion times a year, so a gas station fire is almost a 1 in a billion shot. Additionally, in almost every case, the fire results in either no injury or a minor injury (singed hair). Only one person was killed within the time frame of this study.

I guess my point is that you could probably hold a road flare at a gas station and not have any problems, unless there's some freak pocket of gasoline vapor in the right place and the right time.

*edit*

Reading the details of each incident, it appears that almost all of them (if not all, didn't read every one, but all of the first 20ish) were caused by a spark directly at the fuel tank. None (that I've read so far) were caused by a spark more than a few inches away from the nozzle. Smoking a cigarette while refueling appears to be mostly safe as long as you don't put the cigarette next to the nozzle or gas cap while pumping.
 
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  • #22
BobG said:
http://www.esdjournal.com/static/Static_Fires.pdf

161 from 2000 to 2004

People fuel their vehicles about 16 billion to 18 billion times a year.

Looks like that study is from around the world, the one I posted was only from the US.
 
  • #23
I won a bet with my last boss over this issue and there may be a thread around here where I talked about it a few years ago:
Evo said:
Of course with my luck, my static cling will blow up the entire station.
That is a typical cause of fire at a gas station and there are a number of videos on youtube of it happening. It's pretty entertaining since it always happens right when you go to grab the nozzle from the tank, shock it, and a flame shoots out and goes up your arm. Very funny stuff.

I also seem to remember someone like the NTSB tracking stats on them and it happens several times a year IIRC. I'll look for the stats...
 
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  • #25
Here's a news report on the issue...not all end with just some humor... http://www.cbsnews.com/video/watch/?id=639389n&tag=related;photovideo

...It says 78% happen to women because more women than men get back in their cars.

Here's an article with some stats:
Renkes said he has studied the issue of fires at gas pumps for 12 years and in that time there have been nearly 200 fires which appear to have been caused by static electricity.
http://abclocal.go.com/wpvi/story?section=news/local&id=7320077

...but deaths are rare because as you see in the video, it isn't actually all that easy to make the fire spread, nor does a little fire tend to lead to an immediate explosion.

[edit] Heh, sorry guys, I didn't see the last few posters already did that research.
 
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  • #26
Some gas stations have fire suppression systems. They can be triggered accidentally. Don't push the big red button if you don't know what it is.

 
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  • #27
You're being a little hard on Evo here, Russ. Now, if she was refueling her chainsaw in the back of her pickup truck equipped with a BedLiner, that would be different...
 
  • #28
edward said:
Don't push the big red button if you don't know what it is.

Now there's some good advice in general. o:)
 
  • #29
berkeman said:
You're being a little hard on Evo here, Russ. Now, if she was refueling her chainsaw in the back of her pickup truck equipped with a BedLiner, that would be different...
Is the chainsaw running?
 
  • #30
While pumping gas, if you can smell gas you are in a flammable atmosphere, step to clean air and watch your gas pump. Please do not leave children strapped into car seats while pumping gas there is just no way you can remove them fast enough. Remember you may not be smoking but what about the guy on the other side of the pump or the young mother on her cell phone. I am surprised there are not more accidents at the pump, but my favorite is the drivers that upon finding their car is on fire will pull into the closest gas station.
 
  • #31
petm1 said:
the young mother on her cell phone

Yep, young mothers, especially when talking with their husbands refusing to help with kids/shopping/laundry, tend to blow up quite often.

But I have never seen one exploding into flames. More like tears, and that puts fire out.
 
  • #32
petm1 said:
the young mother on her cell phone.

What's wrong with cell phones?

Did you know there has never in the history of cell phones been a gas station fire caused by a cell phone? Never. Not one. You're quoting an urban legend.

The Mythbusters did their best to try and make one blow up. They put in in a small box saturated with gasoline fumes, and if I recall correctly, even removed the cover from the phone, but still couldn't make it blow.
 
  • #34
Completely off topic, she wasn't smoking.
 
  • #35
Borek said:
Completely off topic, she wasn't smoking.

She was smoking. Smoking hot.
 
  • #36
Jack21222 said:
What's wrong with cell phones?

Did you know there has never in the history of cell phones been a gas station fire caused by a cell phone? Never. Not one. You're quoting an urban legend.

The Mythbusters did their best to try and make one blow up. They put in in a small box saturated with gasoline fumes, and if I recall correctly, even removed the cover from the phone, but still couldn't make it blow.

I'm sure glad. Having replaced a fuel pump, I'd never drive again if they managed to make gasoline explode with a cell phone.

And the heck with all the written literature. Right after you've successfully replaced your first fuel pump, you have to do a serious mental check before you turn the ignition key to see how well your repair job went. When you insert your new fuel pump and all of those electrical wires into your gas tank, you definitely have the feeling you've just created a bomb. It's a lot easier to start your car when you don't know what's sitting inside your fuel tank.
 
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  • #37
As a kid, I freaked when I saw my cousin shooting matches into a barrel of diesel. How was I to know the stuff wouldn't light? That one can really throw a person.
 
  • #38
Jack21222 said:
What's wrong with cell phones?

Cell phones are a distraction and they are not rated to be used within a flammable atmosphere.
 
  • #39
Back in the old days before people knew anything about child safety, my mom used to leave us kids sitting in the car while she ran inside to pick up a few things. So, naturally, as soon as I was tall enough to reach the gas pedal, I could finally mash the gas pedal repeatedly while pretending to drive.

Pump enough gas into your cylinders and you can't ignite it even if you repeatedly light a spark directly in the cylinder.
 
  • #40
Evo said:
Of course with my luck, my static cling will blow up the entire station.

I'm pretty sure that your static cling has blown up more than a couple of things, but a gas station might be out of even your league.
 
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  • #41
Jack21222 said:
What's wrong with cell phones?

Did you know there has never in the history of cell phones been a gas station fire caused by a cell phone? Never. Not one. You're quoting an urban legend.

The Mythbusters did their best to try and make one blow up. They put in in a small box saturated with gasoline fumes, and if I recall correctly, even removed the cover from the phone, but still couldn't make it blow.
They can set off certain flammable gases. In certain factories, customers can only uuse a certain type of certified cell phone, they cost $2,300-$3,200 a piece.
 
  • #42
Evo said:
They can set off certain flammable gases. In certain factories, customers can only uuse a certain type of certified cell phone, they cost $2,300-$3,200 a piece.

I would love to see something more on the subject.

What I mean is that I fail to see possible problems with correctly working cell phone - amount of energy it emits and the way the energy is emitted (wavelength) should be not a problem. So I doubt it is a matter of setting off gases by the emission, more like phone has to be certified so that in no circumstances it can get hot due to internal short circuit or something.
 
  • #43
Evo said:
They can set off certain flammable gases. In certain factories, customers can only uuse a certain type of certified cell phone, they cost $2,300-$3,200 a piece.

That could mean any number of things if the gas isn't known. I guess some gases could be extremely flammable (hydrogen or coal dust, for example).

Cell phones could conceivably ignite natural gas (which is mostly methane) if conditions were just right, but then, so could most of your household appliances, so you wouldn't be making yourself any safer by not using a cell phone in your own house. In most situations, natural gas is safer than gasoline, since natural gas rises and dissipates - it's only the situations where it gets trapped somewhere that it becomes dangerous.

In that sense, it's more dangerous to smoke, talk on your phone (whether cell phone or wall phone), turn on your TV or radio, turn on your lights, or walk around on your carpet in wool socks than it is to use a cell phone in a gas station, since the risk of gases accumulating inside a building are greater than the risks of them accumulating in the open air. (Admittedly, you'd have to have a stuffed up nose not to notice that natural gas was leaking and possibly accumulating in your house, since they add a foul smelling odor to the natural gas that's pumped into your home).

A cell phone just isn't going to ignite gasoline at a gas station: Cell phone usage at gas stations
 
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  • #44
Borek said:
I would love to see something more on the subject.

What I mean is that I fail to see possible problems with correctly working cell phone - amount of energy it emits and the way the energy is emitted (wavelength) should be not a problem. So I doubt it is a matter of setting off gases by the emission, more like phone has to be certified so that in no circumstances it can get hot due to internal short circuit or something.
Motorola has a special "Intrinsically Safe" IS model. The Motorola IS is protected against releasing electrical or thermal energy that may ignite fuel or light a fire or explosion. It's a push-to-talk phone that is safe to use in hazardous areas with flammable gasses.

Intrinsically safe means a device is safe to use in hazardous areas that may contain fuel in the atmosphere, such as flammable gasses or vapors, or combustible dust.

http://www.phonescoop.com/glossary/term.php?gid=221
 
  • #45
That just confirms what I suspect - it is not GSM technology that puts you at risk, but good old problems that may happen with any electrical device.
 
  • #46
Borek said:
I would love to see something more on the subject.

What I mean is that I fail to see possible problems with correctly working cell phone - amount of energy it emits and the way the energy is emitted (wavelength) should be not a problem. So I doubt it is a matter of setting off gases by the emission, more like phone has to be certified so that in no circumstances it can get hot due to internal short circuit or something.

http://www.slashgear.com/sprint-motorola-i365is-intrinsically-safe-rugged-cellphone-0633242/
SAFETY FIRST:

Intrinsically Safe2: The i365IS offers a protection technique for safe operation of electronic equipment in explosive atmospheres, when used with IS battery and accessories.
Bundled Advanced Features (AFU)
Emergency Group Call – Takes priority over all other phone activities and makes a special emergency tone in the phones receiving the call. In an emergency, reach everyone in your group instantly.
Multi-Simultaneous Talk-Group – Listen to up to four talk groups at a time. Don’t miss any important details or safety information.
Isolated Site Operation – Allows user to continue to make and receive group calls on the hub last used, even if the connection is lost. Ensures that no one is left behind.
Status Messages – Send call alerts that include predefined text messages to get right to the point.
Ultra-Rugged Design: The i365IS is a rugged and durable monolith handset certified for military specification requirements including humidity, blowing rain, dust, shock and vibration.

2 Intrinsic safety (IS) is a protection technique for safe operation of electronic equipment in explosive atmospheres. The theory behind intrinsic safety is to ensure that the available electrical and thermal energy in the system is always low enough that ignition of the hazardous atmosphere cannot occur. This is achieved by ensuring that only low voltages enter the hazardous area, and that all electric supply and signal wires are protected by zener safety barriers.

Okay, actually, at those prices, I'd still like to see more on the subject. You'd hope they would have some sort of over voltage protection on all of their phones, or at least the circuits that can be plugged in or have other things plugged into them. I guess the ruggedness of the protection could vary, and the certification is certainly a scary process (not so much for production, but there's not many students willing to test their overvoltage and overcurrent protection the night before they had to demonstrate the electronic device they designed - what if it fails testing?).

I do have a hard time seeing how that IS rating makes the phone worth over 2 grand just based on the few details given.
 
  • #47
BobG said:
http://www.slashgear.com/sprint-motorola-i365is-intrinsically-safe-rugged-cellphone-0633242/




Okay, actually, at those prices, I'd still like to see more on the subject. You'd hope they would have some sort of over voltage protection on all of their phones, or at least the circuits that can be plugged in or have other things plugged into them. I guess the ruggedness of the protection could vary, and the certification is certainly a scary process (not so much for production, but there's not many students willing to test their overvoltage and overcurrent protection the night before they had to demonstrate the electronic device they designed - what if it fails testing?).

I do have a hard time seeing how that IS rating makes the phone worth over 2 grand just based on the few details given.
The I365IS is a newer much cheaper phone, I don't have the list of specs on the $2,000 ones right now. I have clients that have to have those phones at their plants.

The excuse for the high cost is that they are specially built for a niche market, which drives up the cost.
 
  • #48
Borek said:
Yep, young mothers, especially when talking with their husbands refusing to help with kids/shopping/laundry, tend to blow up quite often.

But I have never seen one exploding into flames. More like tears, and that puts fire out.

:smile:
 

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