An ordinary lorry travels on a conventional road outside a built-up area. No justified circumstances prevent maintaining the minimum speed safely. As a general rule, below what speed is travel prohibited?

Correct answer

Half the generic maximum speed indicated for lorries on this type of road.

Below half the category’s general maximum speed on that road: for an ordinary lorry, half of 80 km/h is 40 km/h. Without justified cause, the prohibition applies even when no other vehicles are travelling. Article 49 permits lower speeds when traffic, vehicle or road circumstances prevent maintaining the minimum without risk, and in other regulated cases. Do not accelerate to 40 km/h when that would be unsafe; always adapt speed to conditions.