Chromium hexavalent (CrVI) compounds, often called hexavalent chromium, exist in several forms. Industrial uses of hexavalent chromium compounds include chromate pigments in dyes, paints, inks, and plastics; chromates added as anticorrosive agents to paints, primers, and other surface coatings; and chromic acid electroplated onto metal parts to provide a decorative or protective coating. Hexavalent chromium can also be formed when performing "hot work" such as welding on stainless steel or melting chromium metal. In these situations the chromium is not originally hexavalent, but the high temperatures involved in the process result in oxidation that converts the chromium to a hexavalent state.

Exposures to hexavalent chromium (Cr(VI)) are addressed in specific standards for the general industry, rules concerning OSHA access to employee medical reports, shipyard employment, marine terminals, and the construction industry.

OSHA Standards

This section highlights OSHA standards, Federal Registers (rules, proposed rules, and notices), directives (instructions for compliance officers), and standard interpretations (official letters of interpretation of the standards) related to Cr(VI).

Note: Twenty-five states, Puerto Rico and the Virgin Islands have OSHA-approved State Plans and have adopted their own standards and enforcement policies. For the most part, these States adopt standards that are identical to Federal OSHA. However, some States have adopted different standards applicable to this topic or may have different enforcement policies.

Highlighted Standards

General Industry (29 CFR 1910)

• 1910 Subpart H, Hazardous materials
  • 1910.124, General requirements for dipping and coating operations
    
    
• 1910 Subpart I, Personal protective equipment [related topic page]
• 1910.134, Respiratory protection [related topic page]
  
  
• 1910 Subpart J, General environmental controls
• 1910.141, Sanitation
  
  
• 1910 Subpart Q, Welding, cutting, and brazing [related topic page]
  
  
• 1910 Subpart Z, Toxic and hazardous substances [related topic page]
• 1910.1000, Air contaminants
• Table Z-1, Limits for air contaminants
• 1910.1020, Access to employee exposure and medical records [related topic page]
• 1910.1026, Chromium (VI)
• 1910.1200, Hazard communication [related topic page]

Rules Concerning OSHA Access to Employee Medical Records (29 CFR 1913)

• 1913.10, Rules of agency practice and procedure concerning OSHA access to employee medical records

Shipyard Employment (29 CFR 1915)

• 1915 Subpart D, Welding, cutting and heating
• 1915.51, Ventilation and protection in welding, cutting and heating
  
  
• 1915 Subpart F, General working conditions
  • 1915.97, Health and sanitation
    
    
• 1915 Subpart Z, Toxic and hazardous substances
• 1915.1000, Air contaminants
• 1915.1026, Chromium (VI)

Marine Terminals (29 CFR 1917)

• 1917 Subpart G, Related terminal operations and equipment
• 1917.152, Welding, cutting and heating (hot work)

Construction Industry (29 CFR 1926)

• 1926 Subpart D, Occupational health and environmental controls
• 1926.51, Sanitation
• 1926.55, Gases, vapors, fumes, dusts, and mists
• 1926.57, Ventilation [Note 1926.57(i), Open surface tanks]
  
  
• 1926 Subpart J, Welding and cutting
  • 1926.353, Ventilation and protection in welding, cutting, and heating
    
    
• 1926 Subpart Z, Toxic and Hazardous Substances
• 1926.1126, Chromium (VI)

Federal Registers

• Revising the Notification Requirements in the Exposure Determination Provisions of the Hexavalent Chromium Standards. OSHA Federal Register, Final Rule 75:27188-27189, (2010, May 14).
  
  
• Revising the Notification Requirements in the Exposure Determination Provisions of the Hexavalent Chromium Standard. Advanced Notice of Proposed Rulemaking Hexavalent Chromium Standards; Notification Requirements in the Exposure Determination Provisions. OSHA Federal Register 75:12485-12409 [2010-5731] and Direct Final Rule Hexavalent Chromium Standards; Notification Requirements in the Exposure Determination Provisions. OSHA Federal Register 12681-12686 [2010-5734], (published March 16, 2010 and March 17, 2010, respectively). By these notices, OSHA amends the current standard to include employee notification of exposure determination regardless of exposure levels.
  
  
• Occupational Exposure to Hexavalent Chromium. Final Rules 71:63238-63245, (2006, October 30). Also available as an 86 KB PDF, 8 pages. Implements a settlement agreement entered into by OSHA, the Surface Finishing Industry Council (SFIC), Public Citizen Health Research Group, and the United Steel, Paper and Forestry, Rubber, Manufacturing, Energy, Allied Industrial and Service Workers International Union on October 25, 2006, to resolve SFIC's legal challenge to the standard.
  
  
• Occupational Exposure to Hexavalent Chromium; Corrections. Notice 71:36008-36010, (2006, June 23). Corrects errors in the final rule addressing occupational exposure to hexavalent chromium that appeared in the Federal Register on February 28, 2006.
  
  
• Occupational Exposure to Hexavalent Chromium. Final Rules 71:10099-10385, (2006, February 28). Also available as an 11 MB PDF, 287 pages. OSHA establishes three separate standards covering occupational exposures to Cr(VI) for: general industry (29 CFR 1910.1026); shipyards (29 CFR 1915.1026), and construction (29 CFR 1926.1126).
  
  
• Occupational Exposure to Hexavalent Chromium; Proposed Rule. Proposed Rules 69:59305-59474, (2004, October 4). OSHA proposes to amend its existing standard for employee exposure to hexavalent chromium (Cr(VI)).
  
  
• Search all available Federal Registers.

Directives

• Hexavalent Chromium National Emphasis Program. CPL 02-02-076, (2010, February 23).
  
  
• Inspection Procedures for the Chromium (VI) Standards. CPL 02-02-074, (2008, January 24). Includes a summary of the Chromium (VI) Standards for general industry, construction, and shipyards, and instructions to OSHA compliance officers for the uniform conduct of inspections and enforcement actions.
  
  
• Additional Information
  • Inspection Procedures for Construction Sites Using Portland Cement. (2007, April 16). Instructs OSHA compliance officers not to apply new 29 CFR 1926.1126 for construction site exposures to portland cement. Portland cement is specifically excluded from that standard, even though cement may have trace amounts of hexavalent chromium. Officers are instructed, instead, to enforce existing standards for PPE, sanitation, air contaminants, hazard communication, and recordkeeping. See OSHA's Concrete and Concrete Products - Manufacturing and Construction Safety and Health Topics Page.
    
    
• Search all available directives.

Standard Interpretations

• OSHA has no authority to ban the use of Hexavalent Chromium. (2009, June 19).
  
  
• Whether a pH buffer solution can be used as a cleansing agent for employees who work with portland cement. (2008, April 11).
  
  
• Use of feasible engineering/work practice controls for exposure to Cr(VI) for welding in confined spaces; housekeeping and disposal of large/bulky waste materials. (2007, May 31).
  
  
• Wearing short-sleeved shirts while performing a thermal spray operation with exposure to hexavalent chromium fumes. (2007, January 25).
  
  
• Use of "objective data" to accurately characterize employee exposures to hexavalent chromium during welding operations. (2006, November 14).
  
  
• Search all available standard interpretations.

Hazard Recognition

Workers in many different occupations are exposed to hexavalent chromium (Cr(VI)). Occupational exposures occur mainly among workers who handle pigments containing dry chromate, spray paints and coatings containing chromate, operate chrome plating baths, and weld or cut metals containing chromium, such as stainless steel. The following references aid in recognizing hazards and health effects associated with hexavalent chromium.

Properties

• Chromium (VI) (Hexavalent Chromium). OSHA Chemical Sampling Information. Includes exposure limits set by OSHA.
  
  
• NIOSH Pocket Guide to Chemical Hazards. National Institute for Occupational Safety and Health (NIOSH) Publication No. 2005-149, (2007, September). Provides physical descriptions, exposure limits, measurement methods, personal protection and sanitation, first aid, respirator recommendations, exposure routes, symptoms, target organs, cancer sites, and other information about hexavalent chromium compounds.
• Chromic acid and chromates
• Chromyl chloride
• tert-Butyl chromate

Health Effects

Workers who breathe hexavalent chromium compounds at their jobs for many years may be at increased risk of developing lung cancer. Breathing high levels of hexavalent chromium can irritate or damage the nose, throat, and lungs. Irritation or damage to the eyes and skin can occur if hexavalent chromium contacts these organs in high concentrations or for a prolonged period of time.

General

• Health Effects of Hexavalent Chromium [24 KB PDF^*, 2 pages]. OSHA Fact Sheet, (2006, July). Provides a concise list of industrial sources, symptoms and health effects of exposure to hexavalent chromium, and OSHA requirements for the protection of employees.
  
  
• ToxFAQs for Chromium. Agency For Toxic Substances and Disease Registry (ATSDR), (2008, September). Answers the most frequently asked health questions about chromium.
  
  
• Toxicological Profile for Chromium. Agency For Toxic Substances and Disease Registry (ATSDR), (2008, September). Characterizes the toxicological and adverse health effects information regarding chromium and chromium compounds.
  
  
• Public Health Statement for Chromium. Agency For Toxic Substances and Disease Registry (ATSDR), (2008, September). Describes chromium and its effects on humans.
  
  
• Chromium (VI) (CASRN 18540-29-9). Environmental Protection Agency (EPA), Integrated Risk Information System (IRIS), (1998, September 3). Lists human health effects that may result from exposure to various substances found in the environment.
  
  
• Toxicological Review of Hexavalent Chromium [1 MB PDF, 77 pages]. Environmental Protection Agency (EPA), Chemical Abstract Service (CAS) No. 18540-29-9, (1998, August). Provides scientific support and rationale for the hazard identification and dose-response assessment in the integrated risk information system (IRIS) pertaining to chronic exposure to hexavalent chromium.

Cancer

All forms of hexavalent chromium are regarded as carcinogenic to workers. The risk of developing lung cancer increases with the amount of hexavalent chromium inhaled and the length of time the worker is exposed. Studies of workers in chromate production, chromate pigment, and chrome electroplating industries employed before the 1980s show increased rates of lung cancer mortality. Certain hexavalent chromium compounds produced lung cancer in animals that had the compounds placed directly in their lungs.

• Gibb, H.J., et al. "Lung cancer among workers in chromium chemical production." American Journal of Industrial Medicine (AJIM) 38.2(2000, July 7): 115-126. Describes a study regarding the incidence of lung cancer among workers in chromium chemical production.
  
  
• Report on Carcinogens (RoC). Department of Health and Human Services (DHHS) Public Health Services, National Toxicology Program (NTP). Links to sections of the report.
• Chromium Hexavalent Compounds [136 KB PDF, 4 pages]. Explains the carcinogenicity, properties, use, production, exposure, and regulations regarding chromium hexavalent compounds.

Eyes

Direct eye contact with chromic acid or chromate dusts can cause permanent eye damage.

Respiratory Tract

Hexavalent chromium can irritate the nose, throat, and lungs. Repeated or prolonged exposure can damage the mucous membranes of the nasal passages and result in ulcers. In severe cases, exposure causes perforation of the septum (the wall separating the nasal passages). Breathing small amounts of hexavalent chromium even for long periods does not cause respiratory tract irritation in most people. Some employees become allergic to hexavalent chromium so that inhaling the chromate compounds can cause asthma symptoms such as wheezing and shortness of breath.

Skin

Prolonged skin contact can result in dermatitis and skin ulcers. Some workers develop an allergic sensitization to chromium. In sensitized workers, contact with even small amounts can cause a serious skin rash.

• Preventing Skin Problems From Working with Portland Cement. OSHA Guidance, (2008, February). Provides information about persistent skin rash caused by trace amounts of hexavalent chromium present in portland cement. It has been reported that skin contact from working with wet portland cement can lead to allergic and irritant forms of dermatitis.
  
  
• A Safety and Health Practioner's Guide to Skin Protection. Electronic Library of Construction Occupational Safety and Health (eCLOSH), (2000). Includes illustrations of dry skin, irritant contact dermatitis (ICD), allergic contact dermatitis (ACD), and cement burns.

NOTE: The aforementioned toxicology comes from the Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs), American Conference of Governmental Industrial Hygienists (ACGIH), 6th Edition, Volume 1, and from the references listed above.

Possible Solutions

There are several ways to reduce exposure to hexavalent chromium. Recommended controls vary from operation to operation. The preferred approach is to use engineering controls such as ventilation or equipment and process modification. If these controls are not sufficient, other controls may be implemented, including the use of respirators, eye protection, showering, and changing into street clothes before leaving the plant. The following references provide possible solutions for hexavalent chromium hazards in the workplace.

• Preventing Skin Problems from Working with Portland Cement. OSHA, (2008). Employees may suffer dermal hazards in working with wet cement such as cement burns (due to its caustic nature) and inflammation of the skin (either due to irritant or allergic contact dermatitis). This guidance addresses ways to prevent or minimize skin problems through the proper selection and use of gloves, boots and other personal protective equipment such as kneepads; proper skin care and work practices such as use of pH neutral or slightly acidic soaps; and ways of making cement products less hazardous.
  
  
• Small Entity Compliance Guide for the Hexavalent Chromium Standards [286 KB PDF^*, 63 pages]. OSHA Publication 3320, (2006). Includes guidance on regulated areas, methods of control, respiratory protection, protective work clothing and equipment, hygiene areas and practices, housekeeping, medical surveillance, communication of hazards to employees, recordkeeping covered by the new standards and an extensive appendix of industry operations or processes associated with occupational exposure to Cr(VI).
  
  
• Hexavalent Chromium. National Institute for Occupational Safety and Health (NIOSH) Workplace Safety and Health Topic. Includes NIOSH comments in response to OSHA's request for Information, NIOSH databases, resources, health hazard evaluations and other related safety and health topics.

Welding

• Felker Brothers Corporation, Marshfield [377 KB PDF, 24 pages]. National Institute for Occupational Safety and Health (NIOSH) Health Hazard Evalution (HHE) Report No. HETA 2003-0114-2924, (2004, January). Evaluation of worker exposures to chromium and other metals during manufacture of stainless steel products and fabricated piping systems.

Autobody Repair

• Control of Dusts From Sanding in Autobody Repair Shops. US Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Publication No. 96-105.
  
  
• Control of Paint Overspray in Autobody Repair Shops. US Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Publication No. 96-106.
  
  
• In-Depth Survey Report: Control Technology for Autobody Repair and Painting Shops at Team Chevrolet Colorado Springs, Colorado. US Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Report ECTB 179-18a, (1993, December). Evaluates the ability of three cross draft spray painting booths to control exposure to air contaminants, including chromium.
  
  
• In-Depth Survey Report: Control Technology for Autobody Repair and Painting Shops at Cincinnati Collision Autobody Shop. US Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Report ECTB 179-16a, (1993, September). Evaluates the ability of several types of equipment to reduce worker exposure to air contaminants, including chromium.
  
  
• Control technology for Autobody Repair and Painting Shops at Kay Parks/Dan Meyer Autorebuild Tacoma, Washington. US Department of Health and Human Services (DHHS), National Institute for Occupational Safety and Health (NIOSH) Report ECTB 179-12a, (1992, September). Provides a study of orbital and in-line sanders with built-in high-velocity, low volume exhaust hoods.
  
  
• For additional information on general safety and health concerns, see OSHA's Safety and Health Topics Page on:
  • Dermal Exposure
  • Hazardous and Toxic Substances
  • Indoor Air Quality
  • Medical Access Order
  • Medical Screening and Surveillance
  • Permissible Exposure Limits (PELs)
  • Personal Protective Equipment (PPE)
  • Respiratory Protection
  • Welding, Cutting, and Brazing
  • Ventilation

Exposure Evaluation

Occupational exposure to hexavalent chromium can occur from inhalation of dusts, mists, or fumes containing hexavalent chromium, or from eye or skin contact with hexavalent chromium. The following references provide information on exposure limits and analytical methods used to evaluate hexavalent chromium exposure.

Exposure Limits

• Chromium (VI) (Hexavalent Chromium). OSHA Chemical Sampling Information. Includes exposure limits set by OSHA, the National Institute for Occupational Safety and Health (NIOSH), and the American Conference of Governmental Industrial Hygienists (ACGIH) for hexavalent chromium compounds.

OSHA Methods

• OSHA has developed and validated methods for use by the Salt Lake Technical Center (SLTC) laboratory. The following methods have been adopted by many laboratories for the analysis of chemical compounds.
  
  
• Hexavalent Chromium. Method W-4001, (2001, April). Describes the procedures for wipe sampling of hexavalent chromium.
  
  
• Hexavalent Chromium in Workplace Atmospheres. Method ID-215, (1998, June). Also available as a 319 KB PDF, 35 pages. Describes the sample collection and analysis of airborne hexavalent chromium.
• For air sampling, the recommended method is ID-215, version 2 (see below). The original June, 1998, method is still listed as it contains sections still applicable for wipe and bulk sampling of materials to analyze for hexavalent chromium.
• The original June, 1998, method lists a proposed OSHA PEL for Cr(VI) of 0.5 ug/m³ and AL of 0.25 ug/m³, but these were not issued in the final rule [OSHA Federal Register Final Rules 71:10099-10385].
  
  
• Hexavalent Chromium. Method ID-215 (Version 2), (2006, April).

National Institute for Occupational Safety and Health (NIOSH) Methods

• Chromium, Hexavalent by Ion Chromatography [102 KB PDF, 3 pages]. Method No. 7605, (2003, March 15). Describes the sample collection and analysis of hexavalent chromium. This method is similar to OSHA Method ID-215.
  
  
• Chromium, Hexavalent by Field-Portable Spectrophotometry [104 KB PDF, 5 pages]. Method No. 7703, (2003, March 15). Describes Method No. 7703 as a field portable method of analysis of hexavalent chromium.
  
  
• Chromium, Hexavalent, In Settled Dust Samples [8 KB PDF, 1 page]. Method No. 9101, (1996, May 15). Describes an estimation of the soluble hexavalent chromium content of settled dust.
  
  
• Chromium, Hexavalent [24 KB PDF, 4 pages]. Method No. 7600, (1994, August 15). Describes sampling and analysis of airborne hexavalent chromium.
  
  
• Chromium, Hexavalent. Method No. 7604, (1994, August 15). Indicates this method is less sensitive than method 7600 (colorimetric), but it contains fewer sample preparation steps.

Additional Information

Related Safety and Health Topics Pages

• Toxic Metals

Other Resources

• Hazardous Substance Data Bank (HSDB). National Library of Medicine (NLM), Specialized Information Services (SIS). Provides access to a cluster of databases on toxicology, hazardous chemicals, and related areas.

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