NEMA published ANSI C78.377-2015, American National Standard for Electric Lamps—Specifications for the Chromaticity of Solid State Lighting (SSL) Products, categorizes chromaticity so that accurate descriptions of the white light can be communicated effectively to consumers. This revision to originally developed 2011 standard adds specifications for nominal CCT values of 2200K and 2500K and justifies move from MacAdam ellipses to quadrangles.