SUCCESSFUL REDUCTION OF SILICA EXPOSURES AT A SANITARY WARE POTTERY

Researchers from the National Institute for Occupational Safety and He alth (NIOSH) conducted a joint survey with the New Jersey Department o f Health (NJDOH) to measure crystalline silica exposures and evaluate the adequacy of the existing control measures for reducing these expos ures at a sanitary ware pottery. This survey found that 95% of the per sonal and area samples from the Slip House, Casting, Glaze Spray, and Glaze Preparation Departments exceeded the NIOSH Recommended Exposure Level (87% exceeded the Occupational Safety and Health Administration Permissible Exposure Level) for crystalline silica. Three years later, a follow-up survey found statistically significant reductions in resp irable crystalline silica exposures in two of four plant departments, and statistically significant reductions in area concentrations in all four plant departments. These reductions were accomplished through a combination of automating and enclosing the batching system in the Sli p House and by replacing the mold parting compound with a nonsilica ma terial, altering the method of dry sweeping, cleaning of castings whil e damp, improving exhaust ventilation at the spray booths, and improve d housekeeping.