Australian Standard Bitumen

The properties of bitumen for road construction are defined in AS 2008: Residual Bitumen for Pavements, an Australian Standard that classifies and specifies the characteristics of conventional pavement-grade bitumens most commonly used in Australia.

The most frequently used classes for sprayed sealing works in Australia include:

• Class 170: The most commonly used bitumen class for sprayed sealing.
• Class 240: A higher-viscosity binder than Class 170, used by some road authorities in warmer climates.
• Class 320: A higher-viscosity binder than Classes 170 and 240, occasionally used for sprayed sealing in areas with high pavement temperatures or heavy traffic stresses. This class has largely been replaced by polymer-modified bitumens (PMBs) and multigrade bitumens.

In New Zealand, sealing-grade bitumens are characterized by penetration grade and typically include:

80/100 penetration: Typically used only in hotter regions or for resealing fatty or bleeding seals; roughly equivalent to Australia’s Class 170 bitumen.

180/200 penetration: Commonly used for sprayed seal work; approximately equivalent to the former Class 50 bitumen, which was softer than Australia’s Class 170.

130/150 penetration: A slightly harder grade than 180/200, used as an alternative; its viscosity falls between that of Class 50 and Class 170 bitumens.