The bursting strength and degree of whiteness of mohair fabrics treated with various chemicals were determined before and after exposure to sunlight and ultraviolet light. Results obtained with the ultraviolet light source were not always in agreement with those obtainedafter sunlight exposure, and it is not advisable to use an ultraviolet light source for simulating photodegradation by sunlight. The best protection against sunlight degradation was obtained by using a polyacrylate pigment binder, an ultraviolet light absorber, or certain dyes. -- AATA