Color by this test method is a measure of color-producing impurities present in the thermally stable solids. This test method is suitable for setting specifications and for use as an internal quality control tool.

1.1 This test method covers the visual measurement of the color of thermally stable solids melting below 150^oC. It is applicable only to materials in which the color-producing bodies present have light absorption characteristics quite similar to those of the standards used.

1.2 The following applies to all specified limits in this test method: for purposes of determining conformance with this test method, an observed value or a calculated value shall be rounded off "to the nearest unit" in the last right-hand digit used in expressing the specification limit, in accordance with the rounding-off method of Practice E29.

1.3 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. For specific hazard statements see Sections 7 and 9.