OSHA Compliance Requirements for Hexavalent Chromium (Hexavalent chrome, Chromium 6, Chromium VI) Effective May 31, 2010
Why be concerned about Chromium VI? Hexavalent chromium (Cr VI) is an IARC-1 human carcinogen. According to the EPA, “The best estimate of the excess risk of lung cancer from exposure to hexavalent chromium…is 8 cases of cancer in every 100 workers exposed.” -Environmental Protection Agency, Chromium VI (CASRN 18540-29-9). Other adverse health effects associated with Hexavalent chromium overexposure include irritation of the nose, throat, and lungs. Repeated or prolonged overexposure can damage the mucous membranes of the nasal passages and cause ulcers to form. In some cases the damage is so severe that the septum (the wall separating the nasal passages) develops a hole. Skin exposure to hexavalent chromium over prolonged periods can cause ulcers to form. Some workers develop an allergic sensitization to chromium. In sensitized workers, contact with even very tiny amounts can cause a serious skin rash. Exposure to Chrome 6 can also cause permanent eye damage in some cases.
Employees performing welding or thermal cutting tasks on chromium – containing metals are likely to be over-exposed to Hexavalent Chrome unless engineering controls and / or respiratory protection are used.
Only proven engineering controls (such as source capture air filtration from Gulftech Enterprises, Inc) can eliminate the need for the regulated areas. Filtration (rather than simple exhaust to the outside) allows re circulation of expensive conditioned air and reduces the size of the regulated area and reduces the number of affected employees.
There are generally three ways to maintain air quality:
– Dilution Ventilation (increased airflow in the welding area)
– Ambient air collection using dilution air and a dust or fume extraction device (ambient air cleaners can be mounted above the weld area to capture the weld fume).
– Source capture using a dust or fume extraction device (weld fume arms connected to either a portable fume extraction system or ducted to a dust collector).