Evaluation of existing technologies for the control of workers' exposures to hexavalent chromium-containing mists, dusts, and fumes.
Blade-L; Wallace-M; Khan-A; Topmiller-J; Crouch-K; Bennett-J; Yencken-M; Catalano-J
American Industrial Hygiene Conference and Exposition, June 1-6, 2002, San Diego, California. Fairfax, VA: American Industrial Hygiene Association, 2002 Jun; :36
The National Institute for Occupational Safety and Health (NIOSH) conducted 21 field surveys in selected industries, to characterize workers' exposures to hexavalent chromium-containing airborne particulate and evaluate existing technologies for controlling these exposures. Hexavalent chromium (Cr[VI]) is a respiratory irritant, and chronic inhalation may cause lung cancer. Primary evaluation methods included collection of full-shift, personal breathing-zone (PBZ) air samples for Cr(VI), measurement of ventilation-system parameters such as hood face velocities, and recording of descriptive information about processes and work practices. This presentation is a follow- up to one presented at the 2001 AIHCE summarizing the findings of 12 selected field surveys. The current presentation summarizes findings from the remaining nine surveys. One survey evaluated a ship-breaking facility's metal-cutting operations on chromium-containing materials. Full-shift PBZ exposures up to 27 micro-grams of Cr(VI) per cubic meter of air (ugim3) were measured outside the supplied-air respirators used by the workers, exceeding the 1 ug/m3 NIOSH recommended exposure limit (REL). Another field survey evaluated a ship- yard's welding operations, where Cr(VI) was present in the fume generated when welding on stainless steel. None of the workers' exposures, which ranged from less than the mini- mum detectable concentration to 0.96 ug/m3, exceeded the REL, despite inconsistent use of local exhaust-ventilation systems. Other operations evaluated include chromium electroplating, welding in construction, a stainless-steel foundry, chromate-paint removal with abrasive blasting, alloy-spray coating, and the manufacture of prefabricated concrete products and treated-wood products. Based on results of these surveys and those previously reported, NIOSH researchers have concluded that, in some operations evaluated, hexavalent chromium exposures less than the current NIOSH REL are achievable with good exposure-control measures, while in others, it is unclear if exposures below this level are achievable with existing technology.
Workers; Exposure-levels; Occupational-exposure; Hexavalent-chromium-compounds; Dusts; Dust-particles; Fumes; Particulates; Airborne-particles
American Industrial Hygiene Conference and Exposition, June 1-6, 2002, San Diego, California