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Refueling fires Why?

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Good posts, glad to see everyone staying even keel. I work in Automotive Fuel Handling. Quite involved in understanding/resolving this issue along with others in the Automotive field, now with you folks.
New to forums, so bear with.

Do a little research, you'll find every industry that comes in contact with "Gas" is interested in fuel pump fires, and have been for years. Root cause is next to impossible to determine due to variants in the relatively few investigated cases. As well, everyone still has to produce their individual component within the fuel fire equation.

?Fuelstat - proper fuel/air mix ignites @ .2mJ, what else should I know? Do you measure conductivity of fuel?

 
Fuelstat-
Aren't fuel formulations different in Europe and Australia than in the US? So doesn't your claim that they are experiencing similar problems argue against the gasoline formulations being causative?

We have identified static discharges and fuel volatility as possible root causes, yet you seem to advocate addressing only fuel volatility. Doesn't that cut your chances for solving the "epidemic" in half? Do I hear an axe grinding?

I would not defend EPA's fuel policy competence- especially after the MTBE fiasco- but if you are trying to persuade the inherently skeptical folks in this forum there's a problem, then evidence speaks louder than the emotional sensationalism that is the popular medias stock-in-trade.
 
OK. I have spent the last few weeks looking at pumps here in SoCal area and so far the only ones that have VERY prominant warnings about fire are the Sunoco leaded racing fuel pumps where, presumably and by law, ALL fuel is dispensed into portable containers. No one I have talked to about this problem had heard of it. Most of my fellow racers were aware that they should not fill their cans while still in the vehicle but, most did it anyway, myself included!!! I guess that makes me worse than the average 'Joe' since I know better. (I'll try to do better, mom. I promise)
With the vapor recovery systems mandated in California it would seem to me that the "vapor cloud around the filler neck" would be non existant or nearly so in most cases. Perhaps that is why I have heard nothing of this "problem" around my neck of the woods. Believe me, the local press would be all over it if it occured around here. So far, nothing.

Rod
 
When I get out of my truck in the winter, I have generated a spark at least 250 mm long. I am just thankfull I own a diesel fueled vehicle. I was told, while operating with a refueling team on the deck of a naval war ship that the AVGAS will generate a large amount of static electricity just moving through the hose. therefore we ALWAYS grounded the hose as well as the aircraft....

 
two things about the "epidemic",
#1 if it is true that most of the fires happen in fall winter and spring then it does not make sense for increased static being the cause (although it stll could be) the reason is that the lower the humidity the greater the static problem and vice versa, so if static is the variable that is changing then the problem shoud be worst in the summer time.

#2 maybe the vapor recovery systems are part of the problem, instead of the vapor disapating into a large area it is concentrated in the tubes at a presumably more flamable ratio.

all that said I have a great solution, use a static disapative rubber boot for the vapor recovery, and make sure the pump and handle are propperly grounded.

also don't they use differant mixtures in gasoline in the winter than in summer?
 
carnage,

Reading #1 of your post, if we assume static is the problem, shouldn't summer be the safest time of the year?

low humidity = static problem, high humidity = summer?

If the incidents happen more frequently in the drier, colder months of fall-winter-spring, then that's in support of the static theory.
 
I think it depends on the region. Temperate regions typically have wet winters and dry summers, but sub tropical and tropical regions typically have wet summers and dry winters, but this also depends on ocean currents, landforms, and prevailing winds.

As I posted earlier, I think a long and detailed study, useing good scientific method, might be required to accurately explain the problem.

I wonder how many injuries per year there are compared to say slipping in the shower or falling down the stairs. Would the resources be better spent somewhere were a much higher injury rate occurs Regards
pat
 
Weather humidity is "relative" to saturated air at the ambient temperature, while absolute humidity is relative to dry air. I'm not a EE but doesn't static buildup depend on absolute humidity? The cooler the air the lower the absolute humidity and so more static in winter, whereas relative humidity may change from climate to climate but doesn't affect static.

I'm pretty sure this is accurate because I get the snot shocked out of myself, but only between Nov.-Feb.!
 
It's not clear from the discussion whether the fires start at the instant contact is made between the nozzle and the vehicle?

If it doesn't occur at that instant, then there are other factors involved, since the design of the nozzle should(?) include grounding that dissipates any charges prior to fueling?

In California, cold dry weather is the time of highest static build-up, since the absolute humidity is lowest then.

Southern California is further complicated by Santa Ana winds, which are winds that come westward after being dried out over the desert. so we can also get 70+ temperatures and static.

TTFN TTFN
 
IRstuff, the Santa Ana's are blowing here the last couple of days and it's been dryer than hell and in the mid 80f and I haven't noted any significant buildup in static electricity as it relates to me 'getting shocked'. Is it not true that some people seem to suffer from this little 'phenomenon' more than others?
Aside this thread and the one 'blurb' on the telly last year, I still have seen nothing in the press or have I talked to anyone who has even heard of the "problem".
My guess is that more people die from asperating food and choking than by fueling fires. Just a guess, mind you.

Rod
 
I guess it's just what you rub against. Last couple of days in the same Santa Ana's, I've had to ground myself as I get out of the car because I was getting zapped. It's a new car, so maybe there's special static buildup on the fabric.

Then again, maybe you're just a better grounded person ;-)
TTFN
 
10-4 It's the "---special static buildup on the FABRIC (my highlite)". LOL I am not allowed to buy cars that have fabric seats, wife won't allow it. We had vinyl until we got old and now she gets leather. The Model A I drive everyday has 100% wool seats and no static buildup so far.

Rod

PS---I am on the EAST side of the Santa Ana mountains. Why should MY wind be a Santana wind? Shouldn't it be a Temecula wind, or a Pendleton wind?
 
Interestingly, I had thought that they were "santana" as in devil winds and not necessarily associated with a locale.

May be Santa Ana doesn't have anything else that's famous...

TTFN TTFN
 
In spanish the name Santa Ana is pronounced "Santana".
Dallas Raines said they are called that because they come down the Cajon Pass on their way to Santa Ana and who am I to argue with Dallas (He is the ONLY meteorologist on the tube, you know. All other are 'weather people').

Rod
 
I'm not really sure if that's the genesis, because the Mexican general that won at the Alamo was Santa Anna, likewise I believe that Santa Ana is a reference to a saint, while "santana" clearly refers to a devil or the Devil.

TTFN TTFN
 
I live in oregon, the only time humidity drops below 99.5% is in the summer, most years the weatherman announces sometime in early october that it has started raining, and to expect sunshine in about 9 months.
[fish]


 
Automotive is not really my field but I would have thought that a concerted effort to standardize fuel caps and nozzles would allow a design which can be locked in place before there's any flow. I've worked on very hot furnaces with naphtha (believe me, that's a lot worse than gasoline for flash fires) and interlocking the valve works just fine. Also, nozzle re-design worked to separate diesel from gasoline.

Now, all we need is someone who has already set himself on fire to be elected to Washington in a position of power and things will be cleared up in no time.
[bigsmile]
David
 
Good suggestion, but I think it already exists. Doesn't California already mandate a sealed/locked system to reduce evaporative emissions?

My feeling (in the absence of evidence) is that this is a great deal of fuss being made about a problem that statistically is down there in the weeds. Cheers

Greg Locock
 
Not exactly... the seal and lock is essentially procedural in that there is a gasket and boot that is supposed to mate against the fill inlet when the nozzle is properly positioned. As all California cars still need to be compatible with nozzles in other states, there's a limit to how different the California nozzles can be, which, as it turns out, not very different at all.

In essence, if I drive to another state and fill up, I see a bare metal nozzle with the usual handle and valve control. In California, it's the exact same structure, except that there's an open-ended boot around the tip of the nozzle. When you insert the nozzle into the fill tube, you compress the boot against the lip of the fill tube. It's not a complete seal by any stretch of the imagination. Couple that with wear and tear, etc., most of the time, it's got at least 1/8" or more opening somewhere on the circumference of the boot.

I'd have to agree anecdotally with the statistics, since you'd think that would be relatively spectacular news at 11 and I don't remember ever seeing such a story.

TTFN
 
I should have known that, you are right. Is there a vacuum extract system in there to return vapour to the service station's tank or am I telling tales out of school?

I suppose it is obvious to everyone that if you put 10 gallons of fuel into the tank you have to push 10 gallons of vapour out of the tank!

Cheers

Greg Locock
 
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