Silica exposure in hand grinding steel castings.
O'Brien-D; Froehlich-PA; Gressel-MG; Hall-RM; Clark-NJ; Bost-P; Fischbach-T
Am Ind Hyg Assoc J 1992 Jan; 53(1):42-48
A site visit was made to a steel foundry in New Jersey to determine if current workers were at risk of developing silicosis by identifying and evaluating worker exposures to silica (14808607) containing dusts. This facility produced steel and stainless steel castings. Induction furnaces were used to melt and adjust the alloys. Fifteen personal samples for crystalline silica and respirable dust were collected to estimate the exposure to workers who performed chipping and grinding operations using hand held tools. Real time measurements were made on two workers to determine which tools and procedures were the primary exposure sources so that control efforts could be prioritized. The removal efficiency of the air recirculation system employed in the downdraft benches was measured. Four of the 15 personal examples exceeded NIOSH recommended exposures limits of 50 micrograms/cubic meter for quartz. The type of tool used, the direction of the grinding swarf, and the position of the tool inside or outside of the casting caused noticeable exposure differences. The exhaust from the downdraft tables was recirculated back into the foundry. Measurements of dust removal efficiency indicated that an improperly maintained bench offered no protection and that even an apparently well maintained bench removed less than half of respirable sized dust particles.
NIOSH-Author; Airborne-particles; Silica-dusts; Metalworking-industry; Abrasive-grinding; Foundry-workers; Steel-foundries; Dust-exposure; Workplace-studies; Mineral-dusts; Occupational-exposure
American Industrial Hygiene Association Journal
New Jersey Department of Health and Senior Services