It’s been foggy the last few days.

You must have noticed.

And, if you’ve been driving during the misty period, you’ll also have noticed that not many of us seem entirely sure whether we should have your lamps on.

Some drivers are using them, others are not.

And, if past experience is anything to go by, quite a high percentage of those using their extra lights will continue to do so even when it’s not foggy – possibly even when their headlamps are off.

Which is not wise- it could get you fines.

The rule is that you should only use your foglamps if visibility is down to 100 metres or less.

That’s pretty foggy. Not just dark or a bit misty.

Rule 226 of the Highway Code says: You MUST use headlights when visibility is seriously reduced, generally when you cannot see for more than 100 metres (328 feet ). You may also use front or rear fog lights but you MUST switch them off when visibility improves (see Rule 236).

Rule 236 adds: “You MUST NOT use front or rear fog lights unless visibility is seriously reduced as they dazzle other road users and can obscure your brake lights. You MUST switch them off when visibility improves.”

It can be expensive if you forget to turn them off - Police sometimes run spot checks and pull drivers over You might be lucky and get away with a stern telling off – but if things go badly you could he hit with a Fixed Penalty Notice and a fine of £30.