Cell Phone Spark
Cell Phone Spark
(OP)
Is there enough spark energy generated in cell phones to ignite air ladden w/ gasoline fume while cars are being refueled? Just read an article relating several incidents on this topic. I can not seem to believe it.





RE: Cell Phone Spark
Eng-Tips: Help for your job, not for your homework Read FAQ731-376
RE: Cell Phone Spark
RE: Cell Phone Spark
http://www.pei.org/static/index.htm
RE: Cell Phone Spark
http://www.snopes.com/autos/hazards/gasvapor.asp
However.....
There have been cases of **people** creating enough spark to ignite gasoline vapors when they grab the nozzle to remove it from the car. This is discussed in the Petroleum Equipment Institute link cited by stookeyfpe above.
RE: Cell Phone Spark
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
She was fine BTW in case you have never seen the video. She just calmly places the hose back into the cradle once the flames go out. Fairly cool head really.
Eng-Tips: Help for your job, not for your homework Read FAQ731-376
RE: Cell Phone Spark
But we don't have self-service gas stations here, so I'll have to find something else to worry about.
RE: Cell Phone Spark
RE: Cell Phone Spark
RE: Cell Phone Spark
And if you drove a Renault 10 you would understand why a person would want to pump his own gas. The fuel fill was a radiator capped pipe in the engine compartment near the radiator fill. Located directly above the ventilated distributor cap. Spill a few tablespoons of fuel and you have an ignition key triggered fire ball. I can't tell you how many times some slack jawed local would wander around with the gas nozzle until I got out and essentially did the fueling verbally.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
There is an exception to the rule that allows a motorcycle driver to place and remove the nozzle as a result of too many complaints about spills on the paint. But on the whole, I find it a much better system than having to get out in the rain and the wind to do it myself. When the wind is coming out of the gorge, the canopy on the fuel island is in the wrong orientation to do any good at keeping the rain out, and besides, you know it rains here all the time. (Probably not really very funny at the moment for those in northern California.)
RE: Cell Phone Spark
Front page of the paper shows each day's mudslide victims.
Today some guy bought a new house six months ago up in the local hills.. Then a 300' X 600' chunk of the hillside came down thru their house. Poor buggers.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
Lets not forget that some cell phones with defective batteries have exploded and caused fires even without being near a gas pump.
Despite the popularity, "Myth busters" is not an approved testing agency - and sometimes are trying to make engineering judgments far outside of their specialty.
RE: Cell Phone Spark
Short of internal sparking, (which I can't picture in a cell phone). I would believe that it could cause a sensor signal to freak out leading to mis-control of a process that could be very hazardous. But I can see no control systems at or near a gas pump that this would ever apply to(motor on/motor off).
I also agree with your MB as not being the final word... I see total bunglelation frequently on that show. (still fun to watch though)
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
('*' indicates the flaw in the argument...)
http://w
RE: Cell Phone Spark
RE: Cell Phone Spark
Works for me.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
Dan
Owner
http://www.Hi-TecDesigns.com
RE: Cell Phone Spark
There must be a long German compound word that refers to the scientifically-illiterate administrative staff addressing only what they can see with their own eyes buffered from the more complex reality by the vacuum of their own ignorance.
RE: Cell Phone Spark
RE: Cell Phone Spark
Hey, it's just the lawyers. A friend was on a jury for a colapsed deck. The lawyer asked if anyone had worked with wood. The people who raised thier hands were immediately dismissed from the jury pool. They want people who are easily swayed by a weak argument. In the end, this jury was hung till one person said they had to catch a buss at 3 and changed her vote. You don't want people like this deciding why a person blew up!
I went into a rest room and the recirculating cotton towel machine had a label saying not to use the cotton towel to lift heavy machinery. The things that go on in rest rooms! Never thought they might be pulling engines there.
RE: Cell Phone Spark
RE: Cell Phone Spark
They're the very ancient and old fashioned analog FM type from the previous millennia (circa 1999).
RE: Cell Phone Spark
Intrinsic safety views electrical devices from the ability of the circuits to create a spark under operation or failure. IS guidelines not only look at energy sources (batteries), heat generation (resistors, light bulbs) and maximum voltages, but also the circuits ability to store enough energy in the inductance and capacitances to create an ignition source for flammable vapors/liquids. IS standards are designed to be very conservative (sometimes seemingly ridiculous) - but with the idea to keep "Stuff" from "happening". Within a few feet of a gas pump is a potential hazardous environment by definition.
The main issue of a cell phone or pager is NOT the RF - it is things like the battery, vibrator motor, and maybe that charge pump for the LED, florescent, or incandescent bulb backlight. From a IS standpoint, a good portion of a cell phone is unsafe.
How many of you remember as kids the pretty arcing/sparking you could get from your slot cars in the dark? Remember those Boy-Scout fire prevention examples using batteries, a little steel wool, and some gasoline vapors?
Stuff happens even when previously examined in detail by very experienced people and put into practice over years. How long were 747 aircraft in service before TWA fight 800 went up in a fireball over Long Island Sound? Supposedly the vapors in the 747 center fuel tank never reached an explosive ratio. They still don't exactly know what the ignition source was, but the fuel probes are suspect. Prior to this incident it was believed the low energy of the fuel level probes (a capacitance measurement device) was safe.
I have no doubt that under the proper conditions, a cell phone or pager could easily cause a fire at a gas pump. It might be rare, but it could, and possibly already has happened.
RE: Cell Phone Spark
RE: Cell Phone Spark
RE: Cell Phone Spark
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
Don't forget the turn signal with the corroded connection a couple of feet from the gas filler.
I agree with VE1BLL
respectfully
RE: Cell Phone Spark
RE: Cell Phone Spark
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
RE: Cell Phone Spark
This is a recognised issue and one that people do have to be aware of as it can and it does happen. Its a one in a million chance but you go buy lottery tickets dont ya ?
It may never happen but if it does then the losses can be huge. There could be a loose cell in the phone or the likes and there you go an arc hot enough to cause the fule vapour to ignite. Ex rated equipment can deal with and contain ensuring that the combustion products leave cool enough not to cause an issue. Your phone doesnt have that sort of protection so it does cause an issue.
rugged
RE: Cell Phone Spark
21 Apr 06 4:54 = 17 Apr 06 11:22
^C
RE: Cell Phone Spark
Not a one in a million chance. It is not a chance. Each explosion has a definate, but maybe unknown cause.
Some cell phones have independent cells and not soldered tabs. They can bounce and disconnect. The voltage jump is very small and known.
Fuel ignition safety requires a 500 Volt limit. Since cell phones are well below this limit, the cell phone arcs are not involved.
Spreading fear and misinformation is bad to do. It can be counterproductive to true solutions.
What human damage could have been avoided if the energy going into misinformation was directed to problem reduction?
jsolar
RE: Cell Phone Spark
On the one hand, I don't believe that cell phones are a hazard but on the other hand I don't understand your statement "Fuel ignition safety requires a 500 Volt limit. Since cell phones are well below this limit, the cell phone arcs are not involved."
Does this mean that I can use my 200 amp arc welder on the full gas tank? The open circuit voltage is only 70 volts.
????
RE: Cell Phone Spark
Believe it or not our city's fire chief tried it.. He's dead now.
Visigoth; I don't have the tables with me, but if I remember correctly, you need about 9 Volts to set off gasoline.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
Actually I think that I'ts an energy thing and any quoted voltage will have a corresponding current that may not be mentioned. I'm pretty sure we could generate an appropriate send-off for your old Renault with 2 volts from one cell of the battery.
Take lots of pictures!!
Respectfully
RE: Cell Phone Spark
As for energy, you do actually need that voltage +/- 1 or 2V to ignite flammable mixtures and that is even boosted with inductors or capacitors. As far as I know you can not ignite a flammable mixture with less than 9V or so. You can scratch a dry cell all day long and you will not get ignition. Now I am not talking about heating a thin wire up with 40A at 2V I am talking about the sparks from opening a circuit.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
BTW, what did you use for a governor?
Respectfully
RE: Cell Phone Spark
RE: Cell Phone Spark
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I think the general answer to the cell-phone-igniting-a-gasoline-fire while fueling your car at the local self serve is as follows.
1) Yes! A cell phone could ignite gas fumes if it is held next to a dribbling gas nozzle and it malfunctions in an explosive manner.
2) How often does a cellphone explosively malfunction? Maybe 20 a year in the world and how often does it happen during a fueling operation? Not very often. 1.92x10-29times per year.
3) A car is more likely to ignite the gasoline vapors than a cellphone.
4) The RF could not come close to igniting anything.
5) People who get ignited are those who get in and out of a fueling vehicle. Nothing to do with a correctly functioning cell phone.
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waross; Very good question about the gov.. One I cannot at present answer. So far I have only mated the generator to the engine in a vertical over-under chassis via a Gates cogged power belt. I hand throttled it for 10 minutes.
I'll probably work up a microcontroller servo system.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
After a look at the net and various sites, I personally believe that it is possible for a cell phone to malfunction in a way to ignite gasoline vapors under certain conditions. Although this would be a remote possibility, I prefer not to take that chance in such a large tank where the chance of survival of myself, and the team I am with, is zero.
I think safety is about doing what we can. We can have intrinsically safe radios and flashlights, so we do.
We can have a regulation that prohibits people carrying cigarettes and lighters in their pockets, so we do.
We do what we can to eliminate all possibility of accidental death but there are limits. I don't think a regulation prohibiting spark ignition vehicles near the gasoline refilling station is very rational (although we have this regulation on board the tanker) or even a simple regulation where a qualified refueller does the fill up in an approved manner (Would be complains of raised costs).
It is hard enough to get people to quit smoking at refuelling stations. I have never seen or heard of a local incidence of a fuel fire from a local station in my town and I don't want one to happen when I am around the station.
I think that it is a good guideline to try to keep cellphones away from the nozzle of the gas pump. I personally don't mind a little inconvenience to ensure the safety of others.
What about a half way such as asking for cell phones to be kept in the vehicle while refueling.
RE: Cell Phone Spark
I believe the cell phone gas thing is like so much other stuff in our world. There is some hazard associated with just about anything. Everything we do has a risk of killing us. Drinking from a water tap can provide poison or that fatal germ. Taking a shower. Watching a TV. Riding in a motor vehicle. And talking on a cell phone while standing in front of a (now days) sealed vacuum pumped gasoline nozzle. You just have to make that personal decision of what is "too risky for me". I have made the decision that with the sealed vacuum gas nozzle and the chance of my cell phone explosively failing while I'm standing there, the odds of disaster are so long as to be down in the 'noise'. I'm not going to worry about it.
Far more important in all this is just when to use a cell phone and when not. Worrying about not using it while fueling then using it as you drive away out into the streets while driving is a hazard most assuredly 'not down in the noise'. The same could probably be said for operating the gas nozzle, the hazard is doing something wrong while pumping the gas due to a cell phone distraction (CPD - SeaPeaDee).
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
http://www.cpsc.gov/cpscpub/pubs/cpsr_nws33.pdf (Page 11)
Additionally, FMA indicates a lithium ignition risk if the battery casing is ruptured:
h
So while the risk of either is still seemingly remote, they are clearly non-zero.
TTFN
RE: Cell Phone Spark
Most of the 'Exploding Cell Phone' arguments only make sense in the complete absense of cars. In the vicinity of a gasoline pump, that's nonsense.
RE: Cell Phone Spark
But worn or frayed spark plug wire could surely generate a big fat spark. So if you arrange to spray some gas into the engine compartment AND have a faulty wire set...
TTFN
RE: Cell Phone Spark
Cell phones - a thousand (a million?) times less likely.
RE: Cell Phone Spark
How likely is it that a cell phone battery would explode? How likely is it that a person would actually be using the cell phone at the time the battery exploded? How likely is it that someone would be actually filming the person at the very time that the cell phone battery exploded?.
Put these three conditions together and you would probably say it is extremely remote at best. Yet, it has already happened. I saw the video on a 20/20 or 60-minutes type news program a few months ago.
There was an incident about 4 years ago when the vibator of a cell phone cause a flash fire at an oil well (in Texas?) Several people heard the vibrator immediately before the fire. Several people were burned. I wish I had kept a copy of the article. This is no doubt a more hazardous situation that a consumer gas station, but it involves the same elements. There was also a situation on a off-shore oil platform a few years ago involving a cell phone. However online I can find references to the incident but no details.
Like I said earlier - "Stuff Happens"
RE: Cell Phone Spark
RE: Cell Phone Spark
CAR CARS CARS - don't forget the CARS.
Reminds me of commercial airline travel and nail clippers.
RE: Cell Phone Spark
- force a ground wire between the car and the fuel pump before fueling, like in airports.
- or force the cars to drop a chain down to the ground upon ignition off.
- ban synthetic clothes like microfiber, goretex, nylon, fortrel, to reduce the odds of developng static charges.
- ban women customers in self-serve gas stations
- ban Renaults from US territory (oops it's already done, Keith you're an outlaw)
- install a big post sign telling people to discharge themselves on the fuel pump frame before filling up
- force people to put a ground-connected conductive bracer while fueling.
- ban common sense, not enough people have it.
RE: Cell Phone Spark
"- ban common sense, not enough people have it."
(and it cuts into lawyer income.)
"Keith you're an outlaw" No surprise there!
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
And Melone, I do Intrinsic Safety, and devices that mount on those gas tanks at filling stations as part on my engineering work. I once gave a talk to a large group of Boeing sensor Engineers on a new fuel measurement technology just a few weeks after TWA flight 800. I was barraged with questions and comments from a group of what (at the time) seemed to me to be some rather stressed engineers. Two weeks after this presentation, it came out in the news that the focus of the investigation had changed from a missle and to the center fuel tank! I've never forgotten that experience and the way the engineers seem to stress that even the published conservitive standards and that passed tests were not even good enough! The inductance in the windings a vibrator motor alone exceeds safe limits - not to mention that this inductance is fed by brushes running a contact - a V = L*di/dt that in a ideal circuit sends V to infinity when the contacts bounce or switch and i becomes discontinuous.
Like I said - "Stuff Happens" It's only a matter of how much risk we are willing to accept in our society. As it is, if you are pumping gas into your car, you are much more likely to be hit by a drunk driving into the station for another bottle of beer than a cell phone to ignite the fuel vapors. But just because it's less likely does not mean that it will not happen.
RE: Cell Phone Spark
RE: Cell Phone Spark
"The number of replies is inversely proportional to the number of components required in providing a solution."
RE: Cell Phone Spark
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
What if you answer the phone while you are filling the car ?
What if the battery connections are lose or that vibrator aint quite right ?
What if there is enough fuel vapour around your phone ?
What if that spark ignites the fuel ?
What if you get a fright and drop the flaming nozzel and it sprays you with gas ?
What if your clothes catch alight ?
What if the burning fuel finds a way to reach those under ground tanks that are partially full as its mid way between fill ups ?
What if the fuel vapour ignites and blows the tank out the ground ?
What if you die from your injuries ?
Life is full of unknowns - you may answer that phone tell your wife your 10 minutes from home go pay for the gas and then drive home with nothing happening.
BUT What if ?
A risk has been identified an attempt has been made to try and limit this risk. But I can tell you if some schmuk tried to answer the phone beside me while I was filling up my car he would require some surgery to remove the phone. Its not safe - its been proved that its not safe so why have this discussion about it being a risk or not. Id prefer not to take that chance.
Its like mobiles near to UPS units - now Im talking big uns, say 2MW rated its been shown that the phone radiated rf can have an issue with them. Ive been beside one of those units when its tried to mesh with the utility power unsyncronised - not a great place to be and I can say that ones trousers ended up heavily soiled. Ive seen the effect so if someone now tells me not to use a phone near them as they dont like it then I will not use a phone near them.
Like petrol pumps I know what can happen Ive seen the video I know that fire hurts and an explosion could kill, I like life so Im not going to go and risk this by having a conversation...... while I fill up the car.
Rugged
RE: Cell Phone Spark
[And perhaps, "What if the 'schmuk' with the call phone has studied martial arts for 26 years?" Now there's a risk, especially if you're wearing a kilt.
A person's reaction to a 'brazillion-to-one' risk item, when surrounded by hundreds of million-to-one risk items, is....revealing.
RE: Cell Phone Spark
I don't think that anyone would disagree that the probability of a component failure (battery rupture, EL driver malfunction causing a spark, etc.) is NOT 0. However, the likelihood of this even happening is VIRTUALLY 0. You are MUCH more likely to be ignited by static electricity (entering your vehicle while fueling, not turning off the engine, etc., http://w
Finally, there are regulations that we (cell phone designers) must meet regarding the safety of our products. Being a spark generation device is UNACCEPTABLE!
RE: Cell Phone Spark
'brazillion-to-one' risk VE1BLL this reminded me,
A blond was watching the news and the reported said that a brazilan has been killed in an accident and she said that it must have been one hell of an accident to kill a brazillion.....
Im not an aggressive guy but why do they put signs up telling you not to use the phone while pumping gas ? Im sure that petrol companies dont spend money like that if there was no risk identified.
I know someone who runs three forecourts and well lets just say extracting a lions tooth would be easier than getting money out of Shell Esso Jet BP or the like..... So there must be some thing in there to spook them.
Rugged
RE: Cell Phone Spark
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
RE: Cell Phone Spark
http:
TTFN
RE: Cell Phone Spark
You'd think that with CP carriers giving out new phones constantly that no one would need a new battery.
Keith Cress
Flamin Systems, Inc.- http://www.flaminsystems.com
RE: Cell Phone Spark
http:
Note the "five reports of batteries exploding."
Seems like battery explosions are not limited to off-brand batteries.
TTFN