Reducing exposures during the pouring operations of a brass foundry

The focus of this exposure assessment and control technology study was a brass foundry and the lead exposures of workers involved in the transportation and pouring of metal. Controls in place at the foundry included ventilation systems at the furnace and along the continuous and stationary pouring lines. Real-time measurements were made to determine which tasks were the primary exposure sources, and a hand-held aerosol monitor was used to measure real-time aerosol exposures (as a surrogate for lead) in the workers' breathing zones. Data were collected over two 30-min sampling periods while worker activities were monitored using a video camera. Analysis of the data showed that the greatest aerosol exposures occurred during the transportation of an unventilated, full ladle, resulting in an average concentration of at least twice that of the other tasks. The study concluded that the addition of exhaust ventilation such as a moveable hood and duct system during the ladle transport and pouring tasks, and the implementation of a side draft hood at the pigging area, could result in a reduction of worker exposure to aerosols during the continuous pouring operation by up to 40%. The controls and techniques suggested in this study could be applied to pouring operations throughout the industry to reduce worker exposure to metal fumes.