EPA is promulgating a final rule under the Toxic Substances Control Act (TSCA) that requires manufacturers (including importers) and processors of 34 chemicals to conduct in vitro dermal absorption rate testing. These chemicals are of interest to the Occupational Safety and Health Administration (OSHA) of the Department of Labor, and the data obtained under this testing program will be used by OSHA to evaluate the need for "skin designations" for these chemicals. Skin designations are used by OSHA to alert industrial hygienists, employers, and workers to the potentially significant contribution to the overall exposure to certain chemicals which can occur by the cutaneous route. Thus, skin designations encourage employers to consider whether changes should be made to processes involving such chemical substances in order to reduce the potential for systemic toxicity from dermal absorption of these chemicals. Persons who export or intend to export any chemical substance included in this final rule are subject to the export notification requirements in TSCA section 12(b).