This practice describes microscopical examination of plastic compounds to check quality of pigment dispersion. Thin sections of polymers are prepared for observation with transmitted light. Microscopical examination is normally made for grading or classification by comparison against observational standards. Operations are listed for practice generally applicable to many thermoplastic compounds. Details specific to wire- and cable-grade Type I polyethylene is given in Appendix X1. Note 1-There is no similar or equivalent ISO standard. This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.