Driving in fog

Stay safe when visibility is reduced by fog, rain or spray

Use dipped headlights at all times and windscreen wipers and demisters

Use dipped headlights at all times and windscreen wipers and demisters

According to the Highway Code, you must use headlights when visibility is seriously reduced – generally when you cannot see for more than 100 metres (328 feet) or the length of a football pitch.

There's no obligation to use fog lights but if your car is involved in an accident in reduced visibility and its fog lights weren't on, then it may be queried by an insurer.

If you do use fog lights they must be switched off when visibility improves. This applies equally to front and rear fog lights.

When there's fog around visibility can seriously deteriorate in a matter of seconds. Be extra vigilant and drive only as fast as conditions allow and maintain a greater distance between you and the car in front.

Fog lights

Use common sense when it comes to fog lights. Some drivers are worried about dazzling other motorists, and some simply don't know how to turn them on.

Generally it's better to be safe than sorry, so use them when appropriate. Don't keep switching them on and off, though – this can be a distraction, so wait for a consistent improvement in visibility before switching them off - front and back.

Ten tips

  • Use dipped headlights at all times along with wipers and demisters.
  • Familiarise yourself with your front and rear fog lights – know how to switch them on and off – and use them when appropriate.
  • Beware of other drivers not using headlights.
  • Only drive as fast as conditions allow and maintain a greater distance between you and the car in front.  Follow a three-second rule.
  • Tailing someone's rear lights can give a false sense of security and is dangerous.
  • If the road has street lights on, then you probably don't need your fog lights on.
  • Be able to stop within the distance you can see clearly – this is particularly important on motorways and dual carriageways, as vehicles are travelling faster.
  • Don't accelerate to get away from a vehicle that is too close behind you.
  • Check your mirrors before you slow down.
  • At a junction with limited visibility, stop, wind down the window, and listen for traffic. When you are sure it is safe to emerge, do so positively and do not hesitate in a position that puts you directly in the path of approaching vehicles.

(8 November 2011)