USP And EP Visual Color Standards

The USP and EP Color Standards are visual color standars, intended to improve color communication between sites by defining a sample color as being close to physical liquid standard ("near USP F"; "near EP Y2") rather than using words. ("light yellow")

The USP - United States Pharmacopoeia visual color standards consists of 15 matching liquid standards (A-T) derived from 3 primary solutions (cobaltous chloride, ferric chloride and cupric sulfate) mixed with water in variuos ratios.