The ASTM D6441-05 (2024) standard provides two test methods for measuring the hiding power of powder coatings: Method A evaluates the contrast ratio at a given film thickness, and Method B measures the desired film thickness at a 0.98 contrast ratio. The evaluation of hiding power is critical to the cost and value analysis of coatings. The standard applies to electrostatic spray powder coatings, emphasizing the testing of coatings with a minimum CIE-Y reflectance of 15%, and specifying data reporting in SI units to ensure conformity and accuracy of the test.