Definition: Clothing is colorfast if its colors and dyes do not bleed or run from the clothing. Clothing should be tested for colorfastness before using any type of bleach or bleaching solution, or strong cleaning product.
How to Test
To test for colorfastness, find a hidden seam of the garment or an hidden spot. Apply the cleaner to the garment and then dab the area with a clean cotton cloth. If the color removes itself from the garment onto the cloth, you should not use the cleaning product on the clothing.

