AATCC EP 01

The AATCC Gray Scale for Color Change is designed to visually evaluate the changes in color of textiles resulting from colorfastness tests. 

The scale consists of nine pairs of gray chips, which illustrate color differences and provide a corresponding fastness rating from 1 to 5, with 5 indicating excellent color retention and 1 indicating poor retention. 

The AATCC gray scale measures color change. One half of each color chip pair is the same color as the untested specimen before colorfastness testing. The second half of the color chip ranges from the starting color (no loss of color) to white (loss of all color). The amount of contrast between the tested fabric and untested fabric is related to one of the pairs of gray color chips on the gray scale for color change.