1. American Conference of Governmental Industrial Hygienists. (1994 ). Threshold Limit Values . Cincinnati, Ohio, USA, pp. 92 -103 .
2. �ber die gewerbliche Sch�digung der Augenlinse durch W�rmestrahlung
3. Canadian Standards Association. (1992 ). CAN/CSA-Z94.3-92. Industrial Eye and Face Protectors. CSA, Rexdale, Ontario, Canada.
4. CABOT Safety Corporation. (1991 ). AO safety offers a wide selection Of protective lenses (advertising flyer No. 5431).