Exposure Limits

"Hexavalent chromium, a highly hazardous cancer-causing substance, is found in chromic acid mist released into the air as part of the electroplating process. Chromic acid is also a respiratory irritant, whose short-term effects include coughing and wheezing. Noncancerous long-term effects include bronchitis, as well as ulcerations and perforations of the nasal septum."

-- from an EPA toxicological study of chromium

The Occupational Safety & Health Administration (OSHA) clearly stipulates the permissible exposure limit of chromium at the work place. The limits for chromium metal, trivalent chromium, and hexavalent chromium are 1 mg/m³, 0.5 mg/m³, and 5 μg/m³ respectively (8-hour time-weighted averages). For the cancer-causing zinc chromium, NIOSH recommends a 10-hour limit of a detectable 0.001 mg Cr(VI)/m³.