Filling fuel cans on vehicle

[ancientlake]

Well, I started this, so thanks for the opinions. From what I've read, I still don't know.

My take so far: Diesel, not a big worry.
Gasoline in plastic cans in metal bed with no liner: not much risk -- Much greater risk of injuring my back lifting full cans than getting blown up.

Finally, for those who have the 100-200 gallon tanks in their beds, why is that ok, or how is the risk eliminated?
Chris

[Defective]

Any portable can, gas OR diesel needs to be on the ground while filling. Diesel does burn, it just takes more to get it started and it's easier to extinguish.

Plastic or metal, either can be an issue with static. Static electricity is NOT the same as what you use to run your lights. Think about the most common demonstration of static there is. Rub a balloon in your hair & stick it to a wall. Balloons are not conductors. Your hair isn't a particularly good conductor either.

100-200 gallon (or bigger) transfer tanks mounted permanently in the bed of a truck are electrically bonded to the vehicle just like the built in tank. Makes a huge difference.

BUT: Even the built in tank can be a fireball from static electricity. Ever get out of your vehicle on a dry winter day & get zapped? Guess what...that's static electricity. This is more of a problem at full serve stations than self serves for the simple fact that getting out of the vehicle will often discharge the build up. (say ouch)

[David Cockey]

Virtually every driver has filled a gas tank in a vehicle hundreds if not thousands of times. It's the built in gas tank that the vehicle runs on. What's the difference between filling the built in tank, and filling one sitting in the bed? In either case the vehicle is electrically insulated from the ground by the rubber tires.

[MossRoad]

Originally Posted by Wayne County Hose

If you are using a plastic container, fill it wherever you like. The plastic cans are non-conductive and therefore will not produce a static charge.

The plastic will not produce a static charge. The fuel flowing over the plastic will. Plastic will hold a static charge. Just run a cheap plastic hair brush through your hair then hold it near your arm. The hair on your arm will stand up because the plastic brush has been charged.

Please read this article at the CDC website for some advice on refilling both metal and plastic fuel cans.

NIOSH/Hazard ID/ Fire Hazard from Filling Portable Gas Cans in Pickup Trucks and Cars

[PILOON]

One solution would be to do as they do when refueling aitcraft.

We always connected a ground or bonding from the fuel truck or from the pump.

The ground is simply a conductive line (copper) with an aligator clip that we attached to a 'bonding' location on the aircraft.
Generally that is a bare metal ring or otherwise designated spot.
Aviation fuel pumps all have a retractable grounding or bonding line terminated in an aligator clip.

If you wish to be 'safer than sorry' rig yourself about a 10-12 ft wire with aligator clips at both ends.
For a plastic container simply dip the bare wire (and clip) into the plastic container to be filled and clip other end to the fuel/gas pump.

On a metal fuel can clip to bare metal.

All that being said I am sure that the fuel/gas hoses used commercially have wire braiding incorporated in the fuel line and simply touching the nozzle to the filler neck completes the ground circuit, and that (probably) being so a simple 12" length of bare copper wire with aligator clips at both ends would be all the assurance I would need.

In aviation fueling operations the ground is always clipped prior to bringing the nozzle to the filler neck.

Hope this helps.

[horse7]

Originally Posted by David Cockey

Virtually every driver has filled a gas tank in a vehicle hundreds if not thousands of times. It's the built in gas tank that the vehicle runs on. What's the difference between filling the built in tank, and filling one sitting in the bed? In either case the vehicle is electrically insulated from the ground by the rubber tires.

The implication is that the vehicle does not carry much of a static charge when driving into a gas station-- the nozzle is grounded, and once the nozzle is filling the vehicle there is metal to metal contact so the vehicle is grounded. Since we don't hear of numerous exploding and burning cars at gas stations from just routine filling, the issue of initial contact, if any, must be minor.

OTOH, getting out of the vehicle can be fatal....
CNN.com - Little-known dangers at gas pumps - Dec. 6, 2002
http://www.ces.purdue.edu/cfs/progra...ndout-long.pdf.

(leather seats are much less prone to static-- fabric and vinyl are notorious for static. Now we have a reason to buy leather seats!)

However, I don't see why it should make a difference for a PLASTIC container to be either on the ground or in a truck bed, except that if it did go off I'd sure rather it be on the ground than in the bed... and I would definitely NOT want the denser than air filling fumes accumulating in a trunk ... [concrete has passably decent conductivity (it is not an insulator like tires or a bed liner) so putting a metal container on the ground is certainly safer wrt to static]. Perhaps it is also that expecting people to read 7 pages of fine print when filling their vehicles is too much and they would read nothing. Better to lump the plastic with the metal? I guess I'm with the hose guy on this one, non conductive plastic shouldn't matter whether on the bed or on the ground but explaining that to people would be as effective as spitting into the wind.

[gemini5362]

They sell one heck of a lot of plastic gas cans. I dont see a lot of stories about fires when I watch the news. I have seen a lot of folks filling their gas cans in the back of their truck. It is probably not going to be a big worry for me about doing it. If it catches on fire then I will deal with that.

[AndyMA]

Originally Posted by Wayne County Hose

If you are using a plastic container, fill it wherever you like. The plastic cans are non-conductive and therefore will not produce a static charge. You can fill a metal can in the bed if you are careful. Even filling a metal can on the ground, I touch the fill nozzle to the can before I start the pump. Do the same in the p/up bed. If you have a plastic bed liner, the can is insulated from the vehicle anyway.

I'm sorry to say this but what you state is totally incorrect and dangerous. It shows a total lack of understanding about electricity and as an electrical engineer I feel I have to step in and set the record straight. You do not create static electricity with conductive surfaces. You create it with friction on non conductive surfaces. Think about walking across a rug and then touching something conductive or another person -snap a spark created totally from friction on non conductive surfaces.

This same kind of friction can be created by the diesel fuel rubbing on the plastic can during filling. Apparently if the can has ever been used for gas, and is swithed back and forth between diesel and gas there is a film left that is particularly prone to creating static sparks and setting off explosions. I believe ti results in static generation when the gas rubs on the diesel film if I remember right. The Consumer Product Safety Commission published a special alert on this a few years back due to some explosions. You may get away wiith filling diesel and gas can's for years in the bed of your truck untill that one time when atmospheric and other conditions are just right and boom.

Also just another correction from some other posts, the tires on a vehicle are almost perfect insulations, just adding to the ability to created static electricity while filling a container in a vehicle regardless of whether it is conductive or not. The bed liner only makes the situation worse. Some approved containers also contain trace materials to make them slightly conductive.

So just a little advise from someone who gets to read the consumer product bulletins, fill your containers on the ground.

Andy

[brandoro]

All things considered, if a fuel can catches on fire I would much rather not have it in my truck and, if I can lift the fuel can high enough to pour the fuel into my tractor for sure I can lift it from the ground into my truck after filling it. If/when I become unable to lift a full fuel can I will either find an alternate method or else get more cans and not fill them as much. I don't quite fill them now because my tractor tank holds a bit less than a full fuel can when the gage hits 'empty'. I prefer the can to come empty before it spews fuel over my nice shiny tractor.

[horse7]

Originally Posted by AndyMA

I'm sorry to say this but what you state is totally incorrect and dangerous. It shows a total lack of understanding about electricity and as an electrical engineer I feel I have to step in and set the record straight. You do not create static electricity with conductive surfaces. You create it with friction on non conductive surfaces. Think about walking across a rug and then touching something conductive or another person -snap a spark created totally from friction on non conductive surfaces.

This same kind of friction can be created by the diesel fuel rubbing on the plastic can during filling. Apparently if the can has ever been used for gas, and is swithed back and forth between diesel and gas there is a film left that is particularly prone to creating static sparks and setting off explosions. I believe ti results in static generation when the gas rubs on the diesel film if I remember right. The Consumer Product Safety Commission published a special alert on this a few years back due to some explosions. You may get away wiith filling diesel and gas can's for years in the bed of your truck untill that one time when atmospheric and other conditions are just right and boom.

Also just another correction from some other posts, the tires on a vehicle are almost perfect insulations, just adding to the ability to created static electricity while filling a container in a vehicle regardless of whether it is conductive or not. The bed liner only makes the situation worse. Some approved containers also contain trace materials to make them slightly conductive.

So just a little advise from someone who gets to read the consumer product bulletins, fill your containers on the ground.

Andy

Well.....
tires have a high carbon content and are not all that great an insulator. I have been going back and forth with someone else on this topic, with no real resolution since there isn't anything major on the web about the conductivity of tires vs. vehicle static buildup (although there are a lot of people trying to accumulate IP with ideas in this direction if you do a search on the topic).

The issue of alternating the use of gas and diesel seems more to do with the resulting flammability of the vapor:

"the atmosphere in contact with the rising oil surface is not enriched to bring it
[gasoline vapors] out of the flammable range. If circumstances are such that a
spark should occur either across the oil surface or from the oil surface to some
other object, the spark occurs in a mixture that can be within the flammable range,
and explosion can result."
(from: http://www.ntsb.gov/Recs/letters/1999/H99_33_34.pdf )

They are vague on the static source in the NTSB instance cited, they supposed sloshing fluid but really no one knows (maybe he was wearing synthetic long underwear that day?). The issue I have is that the flowing non conductive fluid (in the flowing fluid, for instance, for a hose going to a container) will result in the transport of charge, but the charge in an insulating container will tend to be distributed in the fluid. Charge mobility will be fairly poor (it is supposedly an insulating fluid and container). If the fluid was conductive, the charge would fairly rapidly concentrate on the surface-- or, for instance, on a metal can over time if the charge bleed off was slow enough which may occur for a conducting can being placed on a bedliner vs. the earth.

The argument that the fluid surface would accumulate enough charge from splashing/flowing/etc. for a plastic container being filled, and possible discharge from the fluid surface to the grounded nozzle with the fuel air mixture in the flammable range would apply whether the container was on the ground or in a truck bed. The results are less disastrous with the container on the ground though. [note that almost always the spark would not ignite like an FAE since the gas exceeds the flammable range close to the fuel surface. My guess is that there are a lot more sparks flying out there than people think! ]

I still believe that the reasons for specifying plastic containers are to be filled on the ground is for secondary not primary reasons, as alluded to in my previous post.

I don't have to play an electrical engineer on TV, since I did it the hard way