ISO 8179-2:2017 specifies an external protective coating system which is factory-applied to ductile iron pipeline components as specified in ISO 2531, ISO 7186 and ISO 16631. This coating system comprises a zinc-rich paint followed by a finishing layer that can be bituminous paint or synthetic resin compatible with zinc rich paint coating.
NOTE ISO 8179-1 addresses metallic zinc-based coatings.