The proposed ISO method for testing colorfastness to domestic laundering using a reference detergent incorporating tetra-acetylethylene diamine (TAED), a low-temperature bleach activator, is discussed. The proposed method was altered slightly to account for North American detergents and wash conditions. The changes include using a nonanoyloxybenzene sulfonate activator instead of TAED since it is the predominant bleach activator in North America. Wash conditions are also specified that are relevant to North American conditions. Experimental work showed that this diagnostic test accurately predicted fading due to peroxygen bleach detergents. The color change of the swatches from the diagnostic test was then compared to actual wash conditions to confirm the ability of the diagnostic method to accurately predict multi-cycle colorfastness.