How many rear fog lights

Example In the case of the Volvo S60, pictured here, a couple rear lights illuminate when you push the button, making the Volvo much easier to spot on the highway in the fog and other poor conditions. Volvo lights are one of the most common examples of rear fog lights. The rear fog lamp is a useful safety feature, but issues arise when drivers are unaware of the feature and switch on the fog lights in normal driving conditions.

Therefore, these optional fog lights should not be used as normal driving lights. If your vehicle has rear fog lights, only switch them on when you are driving in fog, snow or other conditions that may prevent another driver from seeing your vehicle. Rear Fog Light — Volvo. Popular Audi 2. I may be wrong but I wouldn't expect much if any research has been done into the subject.

They started off in the 70's if my memory serves me correctly , as a bolt on option, usually suspended from the rear bumper. They were much better, in my opinion, when they were well away from the rear light clusters. Last I heard it was regarded as safer to have one, with two there is a small chance that they will be confused with illuminated brake lights. TooMany2cvs 29, posts 97 months. What I'm trying to find out is what actual research or evidence supports or refutes this view?

JonV8V 6, posts 95 months. Would it be possible to move the discussion, interesting as it is, to its own topic? My question was about what hard, scientific evidence or research if any exists to show whether one or two rear fog lights is safer. If there is none, would it not behove a road safety body IAM?

Pontoneer 3, posts months. Umm, yes, a 5w red and a 21w red light could quite easily look very much like a 5w red and a 21w red light. That's not particularly colour-blindness dependent. But a bright red light each side doesn't look very much like a bright red light each side PLUS a bright red light in the middle.

Anyway, if you've got a single bright red light visible, is it a single rear fog or something with one or even two brake lights out? DocSteve posts months. Car lights have come on in leaps and bounds in the past few, so much so that fog lights almost seem unnecessary these days.

However, UK law dictates that a fog light must be included in the tail lights at the rear of a car, while front fog lights are a useful extra that car makers can use to attract buyers to higher spec models. You'll usually find front fog lights fitted to mid-spec models and upwards, partly as an aesthetic feature that helps differentiate these cars from the most basic versions. Some newer cars have foregone front fog lights in favour of the bright LED daytime running lights DRLs that are now a legal requirement on new models.

These serve a similar purpose to front fog lights when visibility is poor - they're not designed to light your way even though some are so bright that they can do exactly that , but rather they're designed to make you more visible to other road users.

Fog lights are usually operated by a separate switch from the main light controls. Some cars use buttons to activate them - one for the rear, one for the front where front fog lights are fitted - while others feature a collar on the light stalk that you turn back and forth to turn them on.

Some cars use the rotary light switch control to activate them - simply pull the switch towards you, and the fog lights will come on. Most cars will have a symbol in the instrument cluster that will tell you when the fog lights are on. It's usually near the symbol that shows that the lights are on. For rear facing fog lights, the symbol will be pointing in the opposite direction to the headlamp symbol, while the front foglight symbol you've guessed it points in the same direction as the headlight symbol.

Most fog lights are designed to go off when the car's ignition or lights are turned off, so the most likey reason why a car is driving in clear weather with fog lights on is because the driver is not paying attention and has failed to turn them off. Some drivers seem to think that the slightest bit of mist is reason enough to turn on fog lights, but that is certainly not a reason to turn them on.

Fog lights are designed to be used when visibility is severely restricted, chiefly by fog, but also in other poor visibility conditions such as snow or heavy rain. They should only be used when your car's main lights won't be enough to make you visible to other road users. The Highway Code Rule states:. You may also use front or rear fog lights but you MUST switch them off when visibility improves. In the UK, street lights on 30mph roads are placed no more than yards metres apart.

So a good rule of thumb for using your fog lights is whether you can see the next street light up the road from the one you're passing. Use this rule, and it's clear that it's only going to be in the foggiest or snowiest conditions that fog lights should be used.