Sometimes during a stain removal process, the fabric in the stained area virtually disintegrates when only water or spotted agents are applied. This type of damage is not caused by the drycleaner but is the result of prolonged contact with a staining substance. The frequency of this type of damage has led the Textile Testing Laboratory to conduct a study to determine the pH of some common staining substances and their effect on fabric strength. Test fabrics included medium weight cotton twill, wool gabardine, and lightweight silk crepe.