Lighting and Optical Signals
Is it mandatory to switch on the lighting when passing through a tunnel?
Reviewed on 22 Jul 2026
- A No, if the tunnel is lit
- B Only if the tunnel is over 500 metres long
- ✓ Yes, whenever driving through a tunnel or underpass
- D No, daytime running lights are enough
Why this is the correct answer
In tunnels, underpasses, and stretches signposted as such it is mandatory to switch on the lighting, since natural light suddenly disappears and visibility is reduced.
More questions on Lighting and Optical Signals
- Motorcycles must travel with their lighting switched on:
- Should lighting be used when driving on a reversible lane or a lane in the opposite of its usual direction?
- What do a vehicle's position lights indicate?
- What colour are the position lights at the rear of the vehicle?
- How many front and rear position lights must vehicles other than motorcycles carry as a minimum?
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