You're driving in fog that's starting to clear. When should you switch off your high-intensity rear fog lights?
- A When visibility is more than 10 metres (32 feet)
- B When visibility is more than 50 metres (164 feet)
- C When visibility is more than 75 metres (246 feet)
- D When visibility is more than 100 metres (328 feet)
Why this is the answer
Switch off your fog lights when fog starts to clear and visibility improves to more than 100 metres (328 feet). Do not leave your fog lights on when the fog has cleared, because they can cause unnecessary glare or distraction for other drivers.
Why the other answers don't fit
- A
- When visibility is more than 10 metres (32 feet) — Ten metres is almost nothing; you would still be in dense fog.
- B
- When visibility is more than 50 metres (164 feet) — Fifty metres is half the threshold.
- C
- When visibility is more than 75 metres (246 feet) — Seventy-five metres is still below it.
Where this comes from
Rule numbers link to The Highway Code on gov.uk.
Where this question comes from
The question, its options and the explanation are reproduced word for word from the DVSA revision question bank under licence. The licence requires them to appear unaltered, so we cannot reword them and neither can anyone else — that is why you will meet the same wording on other sites. Everything else on this page is written by Theory Hub: the explanation of why each wrong answer is wrong, the topic guide and the revision notes.
Asked in: Lorry & Bus (LGV/PCV)
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