This International Standard describes a method with two procedures for the assessment of pigment or carbon black particle and agglomerate size and degree of dispersion in polyolefin pipes, fittings and compounds. The method is applicable to polyolefin pipes and fittings, as well as raw material in pellet form, with the choice of procedure to be determined by the referring specification. The method is applicable to carbon black pigmented polyolefin pipes, fittings and compounds with a carbon black content of less than 3 %.