The class of the vehicles are determined based on the height and length. There are currently four (4) categories of vehicle class. They are as follows:

Class 1 – a height of less than 1.70m and a length of less than 5.50m.
Class 2 – a height or length which exceeds either 1.70m in height or 5.50m in length.
Class 3 – a height and length which exceeds both 1.70m in height and 5.50m in length.
Class 4 – two wheeled vehicles/bikes