Bitumen is a very viscous liquid or a solid, consisting essentially of hydrocarbons and their derivatives, which are soluble in carbon disulphide. It is substantially non-volatile and softens gradually when heated. It possesses waterproofing and adhesive properties. It is obtained from native asphalt or by processing the residue from the refining of naturally occurring crude petroleum. Bitumen is used in the construction of Sprayed Seals.