Measuring color of decorative glazing in the field may be necessary from time to time in order to resolve perceived color match issues. The following color survey procedure provides the recommended steps to measure and compare units that are ready to be installed and already installed units to mock-up, attic stock or newly produced replacement units and each other. This procedure can be used to measure the near normal single, non gonio-apparent1 reflected color of a transparent, translucent, or opaque, monolithic, laminated and/or insulating glass unit. This document was published in 2020.