Specification :

PG is based on engineering principles to address Common pavement distresses Rutting, Fatigue Cracking and thermal cracking.

Applicable to both conventional and modified bitumen.
Physical properties are measured by specified equipment which directly relates to field performance.
Bitumen is classified based on climatic conditions. For example PG 64-22 grade means that the bitumen is suitable for project location where 7 days max temperature of pavement is 64oC and 7days min. temperature -22oC.

Recommended Storage, Handling and Usage

The storage temperature should not exceed 350° F ( 177° C) . Modified asphalt should not be stored more than two days without agitation. If asphalt is stored longer than one week above 300° F ( 149° C) , it is advisable to monitor aging of the asphalt by checking the DSR. If significant changes in these properties occur, it is advisable to have the asphalt tested for compliance with PG specifications.