In what weather or environmental circumstances is it mandatory to switch on the rear fog light on a truck?

Question

DentroTest · Accepted Answer

The General Traffic Regulations (Article 106(2)) state that the rear fog light must be switched on only when weather or environmental conditions are especially unfavorable: thick fog, very heavy rain, heavy snowfall or dense clouds of dust or smoke. Light fog, drizzle or thin smoke is therefore not enough. Driving on roadways 6.50 meters wide or less with a series of curves is a case in which the front fog light may be used, not the rear one.

In what weather or environmental circumstances is it mandatory to switch on the rear fog light on a truck?

Want to pass the Permit C and C1 (English) theory test first time?