scope:

This evaluation procedure describes the use of the standard depth scales for the determination of the dye concentration required to produce dyeings of visually equal depth for the purpose of colorfastness evaluations. Colorants may have different tinctorial strengths whereby equal concentration dyeings of them may differ markedly in the resulting color depth and colorfastness properties. Using concentrations of colorants which will give visually equal depths will provide a more comparable evaluation.