The mean maximum reflectance of the vitrinite component in coal as determined by this test method is often used as an indicator of rank as presented in Classification D 388, independent of petrographic composition, and in the characterization of coal as feedstock for carbonization, gasification, liquefaction, and combustion processes. If mean maximum reflectance is used as a rank indicator, the types of vitrinites measured shall be specified.

This test method is for use in scientific and industrial research.

1.1 This test method covers the microscopical determination of both the mean maximum and mean random reflectances measured in oil of polished surfaces of vitrinite and other macerals present in coals ranging in rank from lignite to anthracite. This test method can be used to determine the reflectance of other macerals.

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.