One or two rear fog lights - any research on which is bette?

[Ramona]

Thank you for the link. Shame that it costs $30 to obtain a copy of the paper.

Supplementary question: should those of us who belong to motoring organisations (IAM, RoSPA, ABD, etc) be lobbying them to request that the government implement legislation requiring vehicles to have two rear fog lights, based on the above research? After all, many millions are spent on other aspects of road safety, and this would be a (relatively) simple one to implement.

[Sushifiend]

Ramona said:

So if you felt that the best way to get to your destination was by driving at 120mph all the way, while simultaneously texting your friends and undertaking any cars that got in your way, that's what you would do, despite the evidence to the contrary?

I didn't say that I don't modify my behaviour when I am aware of evidence that suggests I ought to, but I also don't seek out evidence where common sense and intuition are sufficient. Did you seek out a paper to find the best way to open a box of cornflakes? I doubt it.

Ramona said:

You don't need to lecture me in netiquette - I've been using Usenet since 1986 - and my original posting was very deliberately framed to say that I was already aware of the arguments on both sides of the divide.

The evidence here suggests that I DO need to. You can't post a question and then complain when the answers aren't as precise as you'd like. This is a discussion forum, not a spreadsheet where only properly formatted entries are permissible.

Ramona said:

I would have expected that a forum such as this - where most of the discussions centre on why we should do certain things - to have been interested in finding out what is the optimal number of rear fog lights.

I'm sure the forum is interested, and I was interested too. Interested enough to read what others have written and since no evidence appeared to be forthcoming - interested enough to want to contribute my own thoughts. If you're not interested in them, you're absolutely free to disregard them. Just so happens that the research linked to by LordGrover backs up my own amateur intuition.

[Foliage]

Worth a read.

https://en.wikisource.org/wiki/Popular_Science_Mon...

ETA - Apparently the best thing is a 3lb cannon..

Edited by Foliage on Friday 11th September 15:14

[LordGrover]

[GoneAnon]

I have no evidence to add but a question to pose:
If a single fog light is best placed towards the offside, what happens when we go to europe (or those blighters come here) and the single fog light is now on the "wrong" side?

Surely the makers should stump up the extra for a bulb holder and bulb on the other side so we have two foglights like we (mainly) used to get.

[DocSteve]

Sushifiend said:

I agree with this. One one occasion I've been in fog so thick that I could barely see anything outside at all. Regular rear lights were invisible even with a care directly in front, and only the presence of the fog lights made cars visible. As you can imagine, we were crawling at perhaps 5 MPH and this was on the M4 at 2am.

I'd much prefer to have see two fog lights in as part of the normal light clusters as it enables me to judge distances. I don't care if I can't tell whether I'm seeing fog lights or brake lights - at least I can see that a vehicle is there!

My own BMW E46 came with only a single bulb holder despite having a fog light lens and reflector in each light cluster. I bought the missing bulb holder as a spare part for about £5 and wired it up from the other side. Now I have two working rear fog lights...

I don't disagree that a fog light penetrates further but if the conditions are such that you can't even see a vehicle "directly in front" apart from the blazing fog light then surely it is time to pull off the road as one might be expected to do in a dust storm in the US or similar? However, I just don't think those sorts of conditions are encountered very often if at all simply due to fog. It might be possible to see a fog light in advance of a modern tail light but does that confer an advantage to anyone?

I am not saying there are no circumstances where a fog light might be appropriate but the point is are they a useful safety device when they are available for use by the general motoring public, or would it be better to remove them as I am aware some manufacturers are pressing for? This information came from a contact in the industry.

[Sushifiend]

DocSteve said:

I don't disagree that a fog light penetrates further but if the conditions are such that you can't even see a vehicle "directly in front" apart from the blazing fog light then surely it is time to pull off the road as one might be expected to do in a dust storm in the US or similar?

Even with fog lights, you could only see cars not more than a few metres in front. Some motorists carried on at perhaps 25 to 30 MPH which I thought was reckless given the conditions. I was tempted to pull over, but the thought of some idiot ploughing into my stationary car put me off stopping and I decided it was safer to keep moving, even though I was struggling to see the lines on the road in front of me. Luckily conditions improved slightly after a few mile, and I'd never seen thick fog like it before, nor have I since.

Edited by Sushifiend on Sunday 13th September 23:26

[Foliage]

Ive been in very very thick fog before, but fog 'banks' so it breaks and thickens, I slowed but what else can you do. Heavy rain can be an issue for visibility too but in the UK that usually only shorted lived too.

I once thought I saw a UFO during thick fog, but thats a different story. (it was just a very high, very odd shaped street light that was illuminating the pole so it looked like a beam lol)

[p1esk]

GoneAnon said:

I have no evidence to add but a question to pose:
If a single fog light is best placed towards the offside, what happens when we go to europe (or those blighters come here) and the single fog light is now on the "wrong" side?

Surely the makers should stump up the extra for a bulb holder and bulb on the other side so we have two foglights like we (mainly) used to get.

I agree with you.

We had Jaguars, XJ6 and XJ12, for a number of years, and they had twin rear fog lights, and twin reversing lights, and I liked that arrangement. However, when we bought our Pug 406 I found it had twin reversing lights, but a single rear fog light and this was at the RH side only. At first I suspected a bulb failure, but the Pug dealer told me that the car was only supposed to have a single rear fog light. Anyhow, when I investigated I found that the rear lamp clusters were identical, but there was no fog light bulb in the LH cluster and no wiring to it, so I had that remedied, whereupon somebody told me that my car was now illegal and that it should only have one rear fog light! I don't know whether that is true, but the car still has two.

[GoneAnon]

Me too - my Volvo had the bulb holder and the wiring, just no bulb so I fitted one and now I'm in the same group as you - a rebel without a damn!

p1esk said:

I agree with you.

We had Jaguars, XJ6 and XJ12, for a number of years, and they had twin rear fog lights, and twin reversing lights, and I liked that arrangement. However, when we bought our Pug 406 I found it had twin reversing lights, but a single rear fog light and this was at the RH side only. At first I suspected a bulb failure, but the Pug dealer told me that the car was only supposed to have a single rear fog light. Anyhow, when I investigated I found that the rear lamp clusters were identical, but there was no fog light bulb in the LH cluster and no wiring to it, so I had that remedied, whereupon somebody told me that my car was now illegal and that it should only have one rear fog light! I don't know whether that is true, but the car still has two.

[Sushifiend]

p1esk said:

whereupon somebody told me that my car was now illegal and that it should only have one rear fog light! I don't know whether that is true, but the car still has two.

It's not true. I modded my car when I bought it and it's never even been mentioned in 11 subsequent MOT tests. Many cars have twin fog lights fitted from the factory, so somebody was spouting nonsense.