2.5 mm penetration only

5.0 mm penetration only

7.5 mm penetration only

both 2.5~mm and 5.0 mm penetrations

exceptionally strong

strong

satisfactory for road surfacing

unsuitable for road surfacing

10%

20%

30%

45%

more than that in tar

less than that in tar

equal to that in tar

none of the above

30 cm

40 cm

50 cm

60 cm