The Environmental Protection Agency and the National Institute for Occupational Safety and Health have sponsored a study of environmental and workplace controls at a domestic secondary lead smelter. The study was intended primarily to develop information important to the effective control of environmental emissions and employee exposure. The study was carried out at East Penn Manufacturing Company in Lyons, PA. It comprised an initial baseline evaluation of environmental and workplace controls. In the followup sampling and analysis to characterize the East Penn lead smelter, the four major areas of interest were process source emissions, baghouse efficiency, employee exposure and workplace controls, and agglomeration furnace performance. Emission rates for specific lead smelting and refining operations were determined on sources hooded for emission control in the sanitary baghouse. These sources were sampled for total lead, total particle loading, and particle size distribution. Test results are reported for various sources upstream and downstream of the control systems. Employee exposures to airborne lead were reduced significantly after the control systems were in operation.