1.1 This test method covers a procedure for the pigment content determination of water-based paints. It is applicable only to pigments that do not decompose or lose weight at temperatures below 500°C. Such pigments include most metal oxides, silicates, and a majority of anhydrous inorganic salts.

1.2 Many water-based paints contain pigments and organic colorants that lose water of hydration or decompose at this temperature. The residual ash should be carefully inspected for changes in color or texture that could indicate a pigment alteration and hence lead to erroneous results. Caution should therefore be exercised when applying this test method to samples containing unknown pigment compositions.

1.3 This standard does not purport to address the safety problems 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.