Driving in fog and how to use fog lights

If there are foggy conditions, think carefully about whether you really need to travel. If you do, check that your car is ready before you go.

• Check your lights. Ensure all your headlights, taillights, and fog lights are working properly and clean. 
• Clean your windscreen and windows, as dirt or smudges can worsen glare, cause misting, and reduce visibility. 
• Check your tyres. Make sure they have enough tread depth and are properly inflated for maximum grip.
• Fill your windscreen wash. Fog can lift grime from the road so make sure you have enough to keep your windscreen clean.

When driving in fog, it’s important to stay alert to protect yourself and others. These steps will help you stay in control and minimise the risks:

• Slow down to give you extra time for unexpected obstacles or sudden stops. Check your mirrors before doing so. 
• Keep a safe distance between you and the car ahead to help avoid collisions. Double your stopping distance to four seconds. You can do this by choosing a fixed point like a tree or building and when the vehicle ahead passes it count up to four. 
• Use your dipped headlights to improve visibility.
• Don’t use your high beams, or full beam headlights, as they can reflect off the fog, making it harder to see. 
• Listen for traffic. Roll down your windows occasionally to hear oncoming vehicles.
• Follow the road markings and use the left-hand edge of the road as a guide if you need to. 
• Don’t use the lights of the car in front to guide you. 
• Avoid sudden movements and brake and steer gently to prevent skidding. 
• If you don’t feel like you can drive safely, pull over when it’s safe and wait for conditions to improve. 

You should use your front and rear fog lights when you can’t see further than 100 meters in front of you (roughly the length of a football pitch). It’s important that you turn them off when visibility improves, as they can dazzle other drivers. If visibility is clear and you have your fog lights on you could be looking at a fixed penalty notice with potentially a £50 fine.

Fog light controls can differ by vehicle, but the symbols are standard. Check your car’s manual for fog light operating instructions.

Front fog light 

The front fog light symbol is a lamp next to a vertical wavy line, with three horizontal lines cutting through it diagonally downward. It usually shows up as green on your car’s dashboard.

Rear fog light

The rear fog light symbol is similar, but it’s pointing in the opposite direction, with the three horizontal lines pointing straight through the wavy line. It usually shows up as an amber or orange light on your dashboard.