Why are the Rules so Hard To Find? (rear fogs today)

Hamilton Felix

Enlightened
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Jan 2, 2010
Messages
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Location
Marblemount, WA, USA
I wanted to find the rules for rear fog lamps where I live, Washington State, USA.

I looked for FMVSS 108, found the part that says rear fogs have to conform to SAE J-1319.

Then I search for the SAE standard and find only sites that want to SELL it to me for pocketful of money.
Is it an expensive secret or something?

And looking at my own State, I find the appropriate part of RCW 46 does not even address rear fog lamps.

I guess one can assume Federal regulations trump State laws (assuming the cop who stops you agrees), so a rear fog is legal.
But it would be nice to have some hard copy to which one could point when stopped by the local cop who does NOT understand about rear fog lamps.

I applaud Scheinwerfermann's effort to build up some legal reference sources. But that's a closed thread. Do those who wish to contribute need to PM first?

It would be nice to know for sure what rules we're playing but, but I guess it's like lot of other things in life... :cool:
 
Please point us at what you found regarding FMVSS 108, which does not actually mention rear fog lamps or SAE J1319. Rear fog lamps are not regulated under Federal Motor Vehicle Safety Standard 108 or any other Federal standard, and AFAIK there is no requirement in FMVSS 108 that rear fog lamps comply with SAE J1319. The only vehicle lighting regulations that formally regulate the rear fog lamp function are the UN (formerly "European") regulations.

SAE standards are commercial products under copyright -- they have to be bought if you want to read them. Fortunately the relevant SAE standard, J1319, is technically identical to the international standard, UN Regulation 38, which can be downloaded free of charge here. I'm not sure that document will supply what you're after, though; it (like SAE J1319) contains the design, construction, and performance requirements for rear fog lamps. It sounds like you're trying to figure out the regulations on installation and usage of rear fog lamps in Washington State, and those rules are not contained in any Federal or UN standard. In your case, they're not contained in any State statute, either, since Washington State is silent on the matter of rear fog lamps. In practical terms this means they are legal if installed, hooked up, and used correctly -- otherwise the many vehicles manufacturer-certified as complying with all applicable Federal Motor Vehicle Safety Standards, and equipped with rear fog lamps, would be illegal in WA; states are not permitted to do that. "Correctly" in this case means in accordance with the specifications contained in UN Regulation 48 (installation of lighting and signal devices); these same specs are in SAE J1319. The latest (linked) version of Reg 48 contains more intricate hookup and switching requirements than older versions; as from the effective date of the latest revision of Reg 48, new vehicles have to be wired up so the rear fog switches off and stays off until manually reactivated if the driver shuts off the headlamps or the vehicle ignition (I think there's an alternate low-cost provision for an audible warning if the rear fog switch is left on with the ignition off).
 
I used to have a Mini Cooper that had rear fog lights. IIRC, they were the same as front fog lights in form factor and lighting, but that was what they looked like via the rear view mirror. My understanding is that they were primarily to help a driver overcoming you in thick fog see YOU, rather than to improve your rear vision, etc.

Were you looking to add lights, or augment/improve an existing OEM set-up, etc?
 
Rear fog lamps are nothing at all like front fog lamps. The only things they have in common are the "fog lamp" part of the name, and the fact that they're meant for use in inclement weather. See here (Wikipedia) and here (looks like a Dan Stern page).
 
Well, that explains why they wanted to sell me J-1319.

I may have missed the target in my searching for FMVSS 108. I got a lot of hits as you'd expect. Now I'm searching again. A number of the hits for "FMVSS 108 rear fog lights" go to remarks that mention FMVSS 108 and some state standards in the same paragraph. Maybe that's what I actually read, a state standard that said "comply with SAE J-1319."

I was just trying to find out what's the proper and legal way to mount a rear fog when you live were I do. I gathered that federal law trumps state law, just wanted to find something specific. Maybe I should write to our State Patrol and see what sort of double talk I get in reply.:rolleyes:
 
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Yep, depends how you want to spend your time. If you want to spend it learning the proper and legal way to mount a rear fog, go look at Reg 48. If you want to spend it writing pointless letters to clueless individuals who won't know what you're talking about, do that instead!
 
Thanks. I think Rule 48 spells it out adequately. If I carry part of that plus supporting documentation that it applies, I have a chance of convincing Barney Fife that I am legal.

Apparently, lawyers aren't the only ones who go by the maxim "if you want to know about the law, don't ask a cop." When my wife was a cop, she carried the most frequently enforced laws with her, but nobody can keep up with all of it and most cops are not up on UN rules or FMVSS.

I am curious about what the State Patrol would say. WSP is said to be one of the top traffic enforcement agencies in the nation. But their primary mission is taking money for the Governor. I don't think I'll waste the time. Careful installation and use should do it.
 
Please point us at what you found regarding FMVSS 108, which does not actually mention rear fog lamps or SAE J1319. Rear fog lamps are not regulated under Federal Motor Vehicle Safety Standard 108 or any other Federal standard, and AFAIK there is no requirement in FMVSS 108 that rear fog lamps comply with SAE J1319. The only vehicle lighting regulations that formally regulate the rear fog lamp function are the UN (formerly "European") regulations.

In your case, they're not contained in any State statute, either, since Washington State is silent on the matter of rear fog lamps. In practical terms this means they are legal if installed, hooked up, and used correctly -- otherwise the many vehicles manufacturer-certified as complying with all applicable Federal Motor Vehicle Safety Standards, and equipped with rear fog lamps, would be illegal in WA; states are not permitted to do that.


So how does this differ from the Dodge Super Lite? Back in '69, it was ruled that States (in this case, Vermont and New York) could refuse to allow the sale of Super Lite equipped vehicles, and that the Federal preëmption to their laws didn't apply. Could the State of Washington add a prohibition of rear fog lamps in light (hurk!) of the fact that they are not a Federally-regulated item? (But in the absence of an actual prohibition, the State could only write for 'improper use' of such a light, not for the presence?)

This is not at all to be argumentative, mind you. Just curiosity (and hazarding the guess that perhaps those cases might have gone differently, with new analysis of the "render inoperative" function. For example, black tape on turn signals will render them inoperative, but not necessarily from the driver's perspective; the driver does not depend on the lights to SEE by, they instead must be SEEN, and so it would be similar to headlights and the effect of the Super Lite).
 
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So how does this differ from the Dodge Super Lite? Back in '69, it was ruled that States (in this case, Vermont and New York) could refuse to allow the sale of Super Lite equipped vehicles

Got some links please? I don't have a whole lot of detail on exactly what went down with the Super Lite; I know some states objected to it because of the strong red and blue fringe effects at the four extremities of the cutoff, but I don't know just how this objection manifested. Keep in mind that the auxiliary low beam (or "mid beam" as it was called at that time) was never a Federally regulated item or function, and so there was no question of Federal preemption. States were (and are) free to regulate the installation and use of auxiliary lighting devices. What states may not do is enforce any equipment standard more stringent than the Federal standard. That is, states cannot prohibit the installation of Federally permitted or required devices or configurations, or require the installation of devices or configurations not Federally required.

Could the State of Washington add a prohibition of rear fog lamps in light (hurk!) of the fact that they are not a Federally-regulated item?

That's something of a gray area. States regulate the use of vehicle lighting equipment (when you have to use headlamps, what distance you have to dim from high to low beam, when you can use fog lamps, etc.) so a state could theoretically enact a law regulating or prohibiting the use of rear fog lamps. It would be harder (but still possible) for a state to enact a law prohibiting the installation of rear fog lamps; they would incur the wrath of the various vehicle manufacturer and importer associations.

(But in the absence of an actual prohibition, the State could only write for 'improper use' of such a light, not for the presence?)

I am having trouble finding a statute under which a WA law enforcement officer could write a ticket related to rear fog lamps at all, let alone one that would stick.

black tape on turn signals will render them inoperative, but not necessarily from the driver's perspective

The driver's perspective does not enter the equation here.
 
Interesting discussion. Naturally, a cop can write a ticket for just about anything. It probably won't stick in court, but it will cost the motorist a day in court and some expensive lawyer time if he's not confident enough to represent himself. I have found myself spending four figures in legal fees to fight a totally made up ticket (dog off leash, and I live in the country and was not there at the time) while being harassed by a sociopathic Deputy and sicko neighbor.

I'd agree with Scheinwerfermann, that it would be hard to write a ticket that would stick. All the same, in gray areas one's odds are better with an attorney. Let's just hope we don't see too many tickets for being safer than most of the rest of the herd...
 
What about the new Land Rover I saw yesterday with TWO rear fog lights illuminated? I'm sure they were fog lights because her running lights were already on when she turned the fogs on. They were as bright as the brake lights above them, which really made it confusing to know when she was actually braking. Correct me if I'm wrong, but I thought a rear fog light can be either on the left or right side of the vehicle but isn't allowed to be illuminated on both simultaneously?
 
What about the new Land Rover I saw yesterday with TWO rear fog lights illuminated? I'm sure they were fog lights because her running lights were already on when she turned the fogs on. They were as bright as the brake lights above them, which really made it confusing to know when she was actually braking. Correct me if I'm wrong, but I thought a rear fog light can be either on the left or right side of the vehicle but isn't allowed to be illuminated on both simultaneously?

Rear fog lamps may be installed in a symmetric pair, or they can be installed as a single lamp. If installed as a single lamp, they must be installed to the left of the vehicle's centerline (in RHT jurisdictions; LHT jurisdictions require them to be on the right of the vehicle's centerline).
 
Got some links please? I don't have a whole lot of detail on exactly what went down with the Super Lite; I know some states objected to it because of the strong red and blue fringe effects at the four extremities of the cutoff, but I don't know just how this objection manifested. Keep in mind that the auxiliary low beam (or "mid beam" as it was called at that time) was never a Federally regulated item or function, and so there was no question of Federal preemption. States were (and are) free to regulate the installation and use of auxiliary lighting devices. What states may not do is enforce any equipment standard more stringent than the Federal standard. That is, states cannot prohibit the installation of Federally permitted or required devices or configurations, or require the installation of devices or configurations not Federally required.
Not the best link, but here: https://bulk.resource.org/courts.gov/c/F2/419/419.F2d.499.13.73.33497.33509.html


The driver's perspective does not enter the equation here.

From Linked articleV. Conclusion

46
In light of these considerations, we conclude that the "aspect of performance" language in the preemption section of the Act must be construed narrowly. We concede, as the First Circuit was unwilling to do, that Standard No. 108 does cover Super Lite. But the coverage is limited severely by the terms of S3.1.2. This subsection of Standard No. 108 is so general that a practical construction of the phrase "impairs the effectiveness of the required equipment" means that an item such as Super Lite is covered only if it physically obstructs the light emitted by the required lamps or if it causes some type of electrical interference with the required lights. Thus, we hold that Standard No. 108 is concerned only with the effects, if any, which Super Lite has on the operation of the required lights so as to reduce or impair the vision of a driver operating a car equipped with Super Lite in darkness or some other condition of reduced visibility. Given the language and structure of Standard No. 108, we do not believe that it can or should be interpreted to apply to any effects which Super Lite may have on the drivers of other vehicles. Since this is the area in which both Vermont and New York have raised objections to the use of Super Lite, their attempts at regulation are not preempted.

Actually, that paragraph is a bit tricky. It seems they're saying the "impair the effectiveness" clause typically means an impairment for the driver, not for other drivers, but my brain seems to be messing with me on this.
 
Rear fog lamps may be installed in a symmetric pair, or they can be installed as a single lamp. If installed as a single lamp, they must be installed to the left of the vehicle's centerline (in RHT jurisdictions; LHT jurisdictions require them to be on the right of the vehicle's centerline).
But doesn't a pair of bright red lights, seemingly as bright as brake lights, housed in the same cluster that includes the brake lights, reduce the conspicuity of the brake lights? We all know how often drivers misuse their front fog lights, but IMO, misuse of rear fog lights is far more dangerous for the reason I just mentioned. While driving behind the Land Rover, for example, I had to make a conscious effort to watch her brake lights, obviously taking my concentration away from the rest of the road.

I know regs have been updated so that fog light switches can't remain permanently in the "on" position (IOW, the driver must manually activate the fog lights), which reduces misuse, but it seems many drivers activate every light possible for no better reason than, "I have 'em, I paid for 'em, I'm gonna use 'em!" Is there a better way, like a single (or pair) of lights mounted individually, away from the typical brake/turn/parking light cluster?
 
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Great link! Dense reading, of course, but a very interesting piece of history. Thanks for digging it up. I can't imagine a case like this playing out this same way today.

(FTR, my "the driver's perspective does not enter the equation here" was in the context of occluded turn signals.)

¶46 is interesting, and history since it was written has largely supported it: to "impair the effectiveness" means to degrade the required, designed, and intended performance of a required item, system, or design feature. That degradation can be by electrical interference or physical occlusion, for example. It is possible to imagine a situation in which a non-required item, system, or design feature such as a highly reflective housing or surface on an accessory lamp or somesuch could "impair the effectiveness" of, say, a low beam headlamp not by blocking part of the beam or screwing up its electric power, but by reflecting light from the high-intensity portion of the low beam into oncoming traffic's eyes. It would be easy to argue that constitutes impaired effectiveness, because low beam regulations contain provisions specifically intended to limit intensity directed towards other drivers' eyes.
 
But doesn't a pair of bright red lights, seemingly as bright as brake lights, housed in the same cluster that includes the brake lights, reduce the conspicuity of the brake lights? We all know how often drivers misuse their front fog lights, but IMO, misuse of rear fog lights is far more dangerous for the reason I just mentioned. While driving behind the Land Rover, for example, I had to make a conscious effort to watch her brake lights, obviously taking my concentration away from the rest of the road.

The rear fog lamps must be at least 10cm from any lit edge of the vehicle's stop lamps or red turn signal. Also, the lit fog lamps notwithstanding, when the driver brakes additional red lamps would turn on, so the change in the lighting would (or *should*) still register.
 
Great link! Dense reading, of course, but a very interesting piece of history. Thanks for digging it up. I can't imagine a case like this playing out this same way today.

(FTR, my "the driver's perspective does not enter the equation here" was in the context of occluded turn signals.)

It's just odd that they say "Given the language and structure of Standard No. 108, we do not believe that it can or should be interpreted to apply to any effects which Super Lite may have on the drivers of other vehicles."

Very weird.

I imagine such a case today could play out differently.

My compromise: You can have and use the Super Lite but only if your rear turn signals are yellow. :)
 
I prefer either a single rear fog, or a pair mounted well away from the stop lights. But still, even with "just barely" compliance with the required minimum 100mm separation between adjacent lit edges of the stop and rear fog lights, not only do you have more lights turning on when the driver steps on the brake, but you also have the central 3rd stop light. I don't mean to say that your concern is invalid; I share it, and I don't like to go very far down the road of comparing the states of various lights on the back of the vehicle to get the message.

Audi has an interesting idea they're playing with: a laser-based rear fog lamp that shines a red transverse line on the pavement a certain distance behind the vehicle, giving following vehicles a clear safe-distance line not to cross. In fog, snow, or rain, the projection of the line forms a triangle -- a red warning triangle. I'd have to see it in person, and there are plenty of regulatory hurdles yet to overcome, but in principle I like the idea.
 
That certainly does sound interesting. For some reason, I'm thinking "laser light show" and visualizing a rapidly moving laser painting a triangle (or other shape) in the fog behind the car. Well, it should be feasible. We've all seen the spinning laser levels used in construction for years now.

I'm not an expert like you, but on my intuitive level, I think I favor a single good rear fog that's well below the tail lights, on the driver's side, but not necessarily vertically in line with the tail light. It would be "bright, different, odd" to the eye accustomed to tail lights. But it wouldn't detract from brake lights or signals.

BTW, thanks for the help. Your effort to create a sticky with lots of legal info is a good one. I started by looking at my state regs, and I'd probably have thought last of a U.N. agreement or rule. It's a complicated world, and quite a few people just don't know what rules apply.
 
Speaking of Scheinwerfermann's excellent sticky, Mr. Scheinwerfermann, would you be able to add links in that thread to some of the documents showing, for example, the junkiness of aftermarket headlamps, etc? So they are quick and easy to find?
 
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