Winter Driving: Fog Lights Guide

By: Motor Easy
driving in fog how to use fog lights

Alert! It's important that fog lights are only used at the correct times, otherwise you can become a danger to yourself and others when visibility is reduced. 

Knowing exactly how to drive in fog and what fog lights do to help can massively increase your safety, but also using fog lights at the wrong time can mean you're dirivng illegally. 

Did you also know that mist and fog are different things? Freezing fog is also another phenomena. 


What Do Fog Lights Do?

An ordinary car light in fog scatters the light particles so the ligh bounces back to you before shining out on the road. The fog lights located at the front of your car are places at bumper level and are cut off at the top. The enables the light to be projected under the fog, as it usually hovers 12-18 inches off the ground. Your rear fog lights are designed to help other drivers see your car whilst driving through the fog.


What Should You Do When Driving in Fog?

If the forecast is due to be foggy then it's vital to know where your fog lights are and if they're working#
- Spotted fog? Slow down and check your mirrors on approach
- When driving in fog, always keep a greater distance from the car in front than you usually would. Leave 
- Fog means there's a lot of moisture in the air, so make sure you're using your wipers and keeping your windscreen demisted (here's our guide to speedy demisting
- If you see a sign labelling 'fog' but the road is currently clear, be prepared to enter fog or for it to be patchy
- If you can't see roughly 100 metres (the length of a football pitch) in front of you, then it's time to use your fog lights
- At no time should you use your high beam as the fog will reflect the light back, which further reduces the visibility
- Don't follow the tail lights of other cars as it can give you a false sense of security and end up in an accident
- If visibility is really limited, wind down your windows at any junctions and crossroads to allow you to listen out for approaching traffic
- Finding the weather too bad? Pull over and wait until the weather has cleared before you continue to travel


When Should You Use Fog Lights?:

Fog lights should only be usd in foggy weather and when the visibility drops below 100 metres (roughly the length of a football pitch). I foyu use your fog lights in times other than this, it affects the safety of others as can dazzle them, and is also illegal.

You could also invalidate your insurance if you have an accident in fog and you weren't using your fog lights. But make sure you don't keep turning them on and off if the visibility is bad, keep them on until you can see over that full 100 metres again. 


Is It Illegal to Drive With Your Fog Lights On?

If visibility is not reduced or when your vehicle is parked, using your fog lights is against the law. The Road Vehicles Lighting Regulations 1989 prohibits the use of front or rear fog lights to dazzle other drivers. Look out for the light on your dashboard to tell you when your fog lights are either on or off. 

All cars are fitted with rear fog lights as a legal requirement in Europe, front fog lights are not as common and if your car does have them only use them when visibility is really severe. 


Further Reading

Winter Driving - Tips For Driving On Ice & Snow

Car Lights & Bulbs - Our Easy Guide

Car Headlights & Bulbs - Everything You Need To Know


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