1.1 This test method covers the determination of the porosity of a white or near white mineral spirits insoluble paint film to indicate the degree to which a subsequent coat will penetrate.

1.2 The texture of the film can affect cleanup that will influence the results of the test. A stain applied to a high-hiding paint will not lower the reflectance as much as the same stain applied to a low-hiding paint of equal porosity. These points must be considered in comparing different paints.

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