Black glass is used in widely referenced high-precision ASTM Method D 2805, and related hiding power test methods. After measuring the reflectance Ro of the dry film, defined area A is scraped from the glass and weighed to obtain M, which is inserted along with A into the equation below to obtain the spreading rate or original wet film thickness. R∞ of the paint is obtained from a separate test application. The hiding power is then calculated from the appropriate Kubelka-Munk equations.

Black Carrara glass panels are used in U.S. Federal Test Method 141-4122 and CGSB Method 1-GP-71-14.7 for measuring hiding power. In both methods the dry film thickness is measured by means of a micrometer. The latter method also provides for direct wet film thickness measurements using a Pfund or Interchemical type of wet film thickness gage, as described in ASTM D 1212. These methods depend on the unique hardness and levelness characteristics of glass substrates. Leneta black Carrara glass is much superior in levelness to striated types that have been used for the same purpose.