The Occupational Safety and Health Administration (OSHA) published the final Hexavalent Chromium (CrVI) Standard on February 28, 2006, with a deadline for full compliance on May 31, 2010. Three versions of the standard apply each to General Industry, Construction, and Shipyards, with similar provisions.
According to the Centers for Disease Control: Cr(VI) compounds are a group of chemical substances containing the metallic element chromium in its positive- 6 valence (hexavalent) state. Occupational exposures to Cr(VI) occur during the production of stainless steel, chromate chemicals, chromate pigments, chrome plating, and thermal cutting.
NIOSH considers all Cr (VI) compounds to be potential occupational carcinogens. Rarely found in nature, Cr(VI) is a toxic form of the element chromium. Other uses for chromium are making bricks in furnaces, leather tanning, wood preserving, and may be in dyes, paints, and inks. Cr(VI) may be inhaled through dust, fumes or mist. Prolonged exposure can cause irritation or damage to the respiratory tract, eyes and skin if it comes in contact with those organs, and lung cancer.
To prevent this, employers must first determine the air quality and element of risk to their employees. An Industrial Hygienist should perform air monitoring and inform the company of the employees’ time weighted average for an 8-hour workday.
OSHA requires engineering controls put into place to eliminate employees’ exposure to Cr (VI) and enhance their protection by the use of respirators or N95 types of facemasks. Respiratory protection requirements are the same in all three standards. Respirators are required in situations whenever exposure levels exceed the permissible exposure limit and/or emergencies.
The OSHA standards also require that separate change rooms are available to prevent cross-contamination of street clothes. The employer must provide disposable clothing, or clean, repair and replace all protective clothing used by employees when they have been exposed to Cr (VI). Medical surveillance is to be available free for the employee who has been exposed to the substance at or above the action level for 30 or more days per year, or those who are experiencing symptoms of adverse health effects. Employees must wash their hands and face at the end of each shift. No eating or drinking in the work areas is permitted.
Most of us may be more familiar with the name Erin Brokovich than this chemical compound. She was credited with investigating the case of alleged contamination of drinking water with Cr (VI) in the southern California town of Hinkley. At the center of the case was a facility called the Hinkley Compressor Station, part of a natural gas pipeline connecting to the San Francisco Bay Area and constructed in 1952. Between 1952 and 1966, a major natural gas and electricity provider used hexavalent chromium to fight corrosion in the cooling tower. The wastewater dissolved the Cr (VI) from the cooling towers and was discharged to unlined ponds at the site. Some of the wastewater seeped into the groundwater, affecting an area near the plant approximately two miles long and nearly a mile wide.. The case was settled in 1996 for $333 million, paid to 634 Hinkley residents, the largest settlement ever paid in a direct action lawsuit in U.S. history.
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