AATCC EP1-2007
This evaluation procedure describes the use of a Gray Scale for visually evaluating changes in color of textiles resulting from colorfastness tests. For instrumental assessment of change of color of a test specimen refer to AATCC Evaluation Procedure 7. A precise colorimetric specification of the differences between the referenceand the 9-step Scale is given as a permanent record against which newly prepared Gray Scales, and old scales that might have changed, can be compared.