Multicolorâ„¢ steels has introduced a wind driven natural ventilation system with a motive to expel hot, humid and moisture laden air from industrial buildings to give a more comfortable clean working environment replacing summer heat and winter damp with fresh air. wind driven ventilators is manufactured from rust-resistant, lightweight galvanized steel. It has been designed to meet as2428.1-1993 to wind speeds of 200 kmhr and to the entry of wind driven rain at a range of 2.5lsec, under cyclonic conditions.