Hexavalent chromium, noted as Cr(VI) or Cr+6, is a toxic form of the element chromium. Hexavalent chromium compounds are used for their corrosion-resistance, durability, and hardness properties.
Rarely found in nature, this form is generally man-made. Hexavalent chromium may be present in pigments, electroplating, wood preservatives/fungicides, and chemical synthesis. Additionally, hexavalent chromium is present in fumes generated during the production and welding of chrome alloys.
OSHA mandated a Hexavalent Chromium Standard for exposures in general industry, shipyards and construction.
The following limits were established for hexavalent chromium exposure:
Action Level (AL) of 2.5 µg/m3 calculated as an 8-hour time-weighted average
Permissible Exposure Limit (PEL) of 5 µg/m3 calculated as an 8-hour time-weighted average