dnewton3
Staff member
I'm going to respond with my thoughts by parsing out yours. Not meant as a taunt; just a means of conversation.
As you mention, there is a chance of static discharge from the seats. But ... how is that altered by a car running or not? The presumption here is that the fuel vapors would somehow make it from the filler neck area to the seat area, and then when you "slide" across the seat, the discharge ignites the vapors. OK - it's a very limited risk, but one that does exist. But the car running or not has no bearing on that situation, right? Fueling the car while running doesn't increase the risk of static at the seating area; that risk is independent of the fueling status, is it not? (again - I'm asking here; trying to reason thru this).
The way I see this:
- static discharge risk at the seat is not altered by a running vehicle
- static discharge at the fuel system is already mitigated by the design of the system. The only way for this to be a "risk" is that the system fails, but again, whether or not the car is running has ZERO effect on this risk
- other electronics in the car also have no bearing on the fueling status vs the running car. Any component in the car which is electrically driven can induce a spark once the car is restarted if the vapors are present, just as easily as if those are present while running.
Further complicating the issue is that of diesel fuels; diesel fuels are flammable but not combustible. Hence, they don't have "vapors" which are a risk of explosion. (I'm using the proper NFPA terms here; this has to do with the ignition temp and vapor pressures). But I presume that the relative distance (across a pump island) to a gas powered vehicle would make for some transient gasoline vapor concern here ... ? The gas vapors could cross over to the running diesel vehicle in some obscure sense?
Also, and I'm going to tip-toe carefully here ... since when did all laws make sense in the first place? It's not like we don't have laws on the books that are outdated and useless, or never were a good idea in the first place. There's a YT channel for Reason magazine. Check out their short videos called "Great moments in unintended consequences; what could possibly go wrong?" These show the nature of well-intended but poorly reasoned laws. Funny (and scary) stuff.
Cops enforce criminal law and civil infractions (and at times, city/town/county ordinances depending upon locale). We don't enforce (nor are we trained to know) all manner of all laws. We don't enforce OSHA laws, nor employment laws, etc. In fact, pretty much every cop I know fuels up with the car running. Not because we do it to thumb our noses at the law, but it's that we pretty much leave our vehicles always running for a multitude of reasons.
I don't have any proof whatsoever. I find myself in agreement with you overall. I just lack the ability to prove my assumptions and conclusions past general "reasoning".
There is another path for static discharge; that comes from the non-conductive fuel running through the fuel hose. However, the static charge (seats or fuel hose) has nothing to do with the electronics of the car itself. If the fuel system is properly grounded in the car, the discharge while filling the tank goes along it's desired ground path. Why would a running car have any more risk than one shut off? Nothing about a running car alters the static path and it's intended ground circuit. It's not that static charge is avoided; it can't be. The issue is one of properly mitigating the charge along a desired pathway.
As you mention, there is a chance of static discharge from the seats. But ... how is that altered by a car running or not? The presumption here is that the fuel vapors would somehow make it from the filler neck area to the seat area, and then when you "slide" across the seat, the discharge ignites the vapors. OK - it's a very limited risk, but one that does exist. But the car running or not has no bearing on that situation, right? Fueling the car while running doesn't increase the risk of static at the seating area; that risk is independent of the fueling status, is it not? (again - I'm asking here; trying to reason thru this).
The way I see this:
- static discharge risk at the seat is not altered by a running vehicle
- static discharge at the fuel system is already mitigated by the design of the system. The only way for this to be a "risk" is that the system fails, but again, whether or not the car is running has ZERO effect on this risk
- other electronics in the car also have no bearing on the fueling status vs the running car. Any component in the car which is electrically driven can induce a spark once the car is restarted if the vapors are present, just as easily as if those are present while running.
Further complicating the issue is that of diesel fuels; diesel fuels are flammable but not combustible. Hence, they don't have "vapors" which are a risk of explosion. (I'm using the proper NFPA terms here; this has to do with the ignition temp and vapor pressures). But I presume that the relative distance (across a pump island) to a gas powered vehicle would make for some transient gasoline vapor concern here ... ? The gas vapors could cross over to the running diesel vehicle in some obscure sense?
I would tend to agree here. This is essentially a draconian law that still exists because old cars still exist, but the typical modern cars don't have this same risk factor; it's miniscule if not completely mitigated by modern designs. It's simply easier to hold onto an old law then to test and have a dichotomy of laws based on age/type of vehicle.
I'd agree; it's a legal issue. One rooted in ol' skool thinking that exists simply because ol' cars still exist at the pumps.
Also, and I'm going to tip-toe carefully here ... since when did all laws make sense in the first place? It's not like we don't have laws on the books that are outdated and useless, or never were a good idea in the first place. There's a YT channel for Reason magazine. Check out their short videos called "Great moments in unintended consequences; what could possibly go wrong?" These show the nature of well-intended but poorly reasoned laws. Funny (and scary) stuff.
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️ Since we are a whole 7 days away from Manteno Illinois... and this thread could be for any car, any time... Can I leave the car running the whole time? Do I have to turn it off to gas up which I will probably have to do about 3 times, top up before leaving NJ because of lower fuel cost to save $$ then again in Ohio if possible and from there should be OK to somewhere in Illinois and that part of journey.. Is there really a need to turn the car off?
