2 ptsD,D1Official number: 6893
While driving a bus, when do you have to switch from high-beam to low-beam lights?

Explanation
Correct answer: When another vehicle is approaching from the opposite direction.
The graphic symbolises the mandatory change from main beam headlights (blue symbol) to dipped beam headlights (green symbol). The driver of a vehicle, including a bus, is required to make this change when an oncoming vehicle is approaching, as the powerful beam of the main beam headlights can dazzle its driver and create a serious hazard in road traffic.