Visibility and Road Hazards
In which case is the use of the rear fog light mandatory?
Reviewed on 9 Aug 2026
- A Whenever it is night-time
- ✓ In very dense fog, heavy snow or strong rain
- C When driving through any tunnel
- D When driving behind another vehicle
Why this is the correct answer
The rear fog light is mandatory in cases of very dense fog, heavy snow or strong rain, because its high intensity allows you to be seen from behind; in good visibility it dazzles and is prohibited.
More questions on Visibility and Road Hazards
- When may the front fog light be used?
- In reduced-visibility conditions, what should the safety distance to the vehicle ahead be?
- With visibility limited by fog, which lane is preferable on a multi-lane road?
- In poor-visibility conditions, what kind of manoeuvres should be avoided?
- If you need to stop in the middle of dense fog, what is the correct action?
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