Many of today’s vehicles have front fog lamps, but what good are they? Not much! Even good fog lamps, are of very limited use to most drivers. The rain and moisture tend to absorb any extra light produced by these lights.
The job of the rear fog lamp is to reveal the position of your vehicle when driving in the fog, snow or other conditions that limit visibility. Your normal taillights are fairly dim, so they are not as likely be seen in foggy weather. Rear fog lights are often placed on the left side of the vehicle, to help mark the corner of the car when vehicles behind are overtaking (passing) it.
Fog lights tend to act as extra headlights when they should actually be lighting the road further ahead.
Good head lighting is foreground light, and that’s what fog lamps produce. But, foreground light is very far down the list of factors that go into the actual, real safety performance of the car’s lighting system. Some foreground light is necessary so you can use your peripheral vision to see where you are relative to your surroundings.
Lights that point further down the road are effective.
Foreground light is far less critical than the light cast further down the road, because at any significant speed, what’s in the foreground is too close for you to do much about. At highway speeds, whatever is in the foreground is too close for you to avoid hitting.
Driving In Fog
Red Rear Fog Lights
A rear fog lamp is a red light, as bright as a brake light, and is manually switched on by the driver in conditions of very poor visibility to increase a car’s visibility to vehicles behind it. A rear fog lamp is usually concentrated in a tighter beam to help penetrate the fog, rain or snow.
Red Rear Fog Lamps
Fog lamps are meant to be used in heavy fog, rain, or snow to help the driver see the edges of the road so they can safely make progress through bad weather at very low speeds. The ones available from the factory aren’t even capable of doing that. And as explained in dense scientific detail in a recent study, they just don’t make anything better. However, there is a potential for a real safety improvement by using a red rear fog lamp.
Driving in the rain
How Many Red Rear Fog Lamps Are Best?
So how many rear fog lamps are best, one or two? Regulations in most of the world, including North America, permit vehicles to be equipped with one or two rear fog lamps. If only one rear fog is fitted, it must be on the driver’s side of the vehicle
Having two is legal, but makes it much more difficult for following drivers to see a change in your car’s rear lights when you step on the brake.