Slabs of ice falling from the roofs of trucks can kill. Rainwater can collect on truck tarpaulins. Often more than 100 litres on a single roof! This water quickly freezes into ice during the winter. And if the truck moves off without this ice first being removed, it can turn into a rolling time bomb. Because the ice may slip off in bends or when the truck brakes suddenly or – even worse – when it is travelling through comparatively warm tunnels – and fall at speed to the ground and so become a deadly missile. The slabs of ice, which may in some cases weigh up to 100 kilograms, then fly off with a deadly momentum at the same speed the truck is travelling at and crash into the vehicles behind or into the oncoming traffic.