The properties of bitumen for roadmaking are specified in AS 2008: Residual Bitumen for
Pavements. This Australian Standard classifies and specifies the properties of conventional
pavement-grade bitumens most widely used in Australia.
The following classes are most commonly used in sprayed sealing works in Australia:
• Class 170: the most commonly used class for sprayed sealing
• Class 240: higher viscosity binder (compared to C170) used by some road agencies
in warm climates
• Class 320: higher viscosity binder (compared to C170 and C240) sometimes used
for sprayed sealing in areas where pavement temperatures or traffic stresses were
high, but has been largely superseded by PMBs and multigrade bitumen.
In New Zealand, the sealing grade bitumens are characterised by penetration grade and
consist of:
• 180/200 penetration: generally used in sprayed seal work (the approximate
equivalent of Class 50 bitumen which was a softer class of bitumen than Class 170
used in Australia in the past)
• 130/150 penetration: a slightly harder grade used as an alternative to 180/200
(approximate viscosity between that of Class 50 and Class 170 bitumen)
• 80/100 penetration: generally only used in sprayed seals in hotter areas or when
resealing fatty or bleeding seals (the approximate equivalent of Class 170 bitumen).