Class 170 bitumen is widely used in sprayed sealing and light asphalt applications to provide durability and fatigue resistance. It is also used to manufacture cutback bitumens, bitumen emulsions and modified bitumens.
Class 240 bitumen is for use in sprayed sealing applications where the local road agency has a preference for a slightly more viscous bitumen than Class 170.
Class 320 bitumen is most commonly used to manufacture asphalt mixes. Due to its higher viscosity, stiffer asphalt mixes can be produced to improve resistance to shoving and other problems associated with higher temperature and traffic loads.
Class 450 bitumen is for use in the manufacture of asphalt mixes where the local road agency has a preference for a slightly more viscous bitumen than Class 320.
Class 600 bitumen is primarily used to manufacture extra heavy-duty asphalt pavements that need to endure substantial traffic loadings.