Bitumen, by definition, is a mixture of hydrocarbons made from crude oil refining. This material is thermoplastic and its hardness depends on temperature. The relationship between temperature and bitumen hardness depends on the source of the crude oil and the refining method. Bitumen is completely soluble in carbon disulfide (CS2) and has the ability to adhere and be waterproof. It is mainly composed of hydrocarbons and is usually made of about 80% carbon and 15% hydrogen, the equilibrium of which is oxygen, nitrogen and other rare particles. Infiltration grade bitumen is commonly used on road surfaces and minor industrial applications. The permeability of bitumen hardness is determined by measuring the depth at which a standard load needle penetrates vertically in 5 seconds. Bitumen is stored at 25. C.