November 14, 2006

American Bakers Association
Automotive Service Association
National Automobile Dealers Association
Sheet Metal and Air Conditioning Contractors National Association
The Steel Tank Institute/Steel Plate Fabricators Association

c/o Mr. Douglas Greenhaus
National Automobile Dealers Association
8400 Westpark Drive
McLean, VA 22101-3591

Dear Mr. Greenhaus:

Thank you for your letter to the Occupational Safety and Health Administration (OSHA) concerning the new standards for hexavalent chromium. This reply letter constitutes OSHA's interpretation only of the requirements discussed and may not be applicable to any question not detailed in your original correspondence. Your paraphrased request and our response are below.

Request: You requested guidance on whether your air sampling protocol to accurately characterize employee exposures to hexavalent chromium during welding operations was acceptable to use by employers represented by your industry groups to comply with the "objective data" option in 29 CFR 1910.1026(d)(3) and 29 CFR 1926.1126(d)(3).

Response: The air sampling protocol you attached for our review specifies that air sampling for hexavalent chromium shall be conducted in accordance with [OSHA] Sampling Method ID-215 or other approved analytical method, and that the air sampling is to be conducted in accordance with generally accepted industrial hygiene practices. In addition, you listed several parameters of the workplace operation and other environmental factors that would be important in documenting the conditions affecting the exposure results, including: the type of welding process; the amount of chromium in materials used; the orientation of the welder to his work and other work practices; the presence of any engineering controls, such as local exhaust ventilation; and several other factors.

At the outset, it should be noted that OSHA does not approve or endorse any specific air monitoring guidelines/protocols used to obtain objective information regarding expected employee exposures to air contaminants. Your attached protocol is generally consistent with accepted industrial hygiene practices for air sampling. However, we do recommend you also account for whether and what type of shielding gas is used in the welding operation; the distance from the point of welding to the local exhaust ventilation, if used; and whether the welding operation is performed indoors, outdoors, or in a confined space. We further refer you to OSHA's website,http://www.osha.gov, where you may follow the links for Chemical Sampling Information, leading to specific sampling and analytical methods for hexavalent chromium or chromium (VI). You will find that OSHA recently updated its OSHA Sampling Method ID-215 for improved accuracy.

We offer a few other comments concerning your air sampling protocol for employers planning to use the resulting data as "objective data" under the standard:

• Where objective data are used to satisfy the exposure determination requirement, the employer must establish and maintain an accurate record of all the information it relied on. This record must include: the specific chromium-containing material in question; the source of the objective data; the testing protocol and results of testing or analysis of the material that releases chromium (VI); a description of the process, operation, or activity involved and how the data support the determination; and any other data relevant to the process, operation, activity, material, or employee exposures (71 FR 10370).
   
• Since objective data may be used to exempt the employer from provisions of the standard or provide a basis for selection of respirators, it is critical that this determination be carefully documented. Reliance on objective data is intended to provide the same degree of assurance that employee exposures have been correctly characterized as air monitoring would have. Records must demonstrate a reasonable basis for the underlying exposure determination (71 FR 10370).
   
• OSHA's term "closely resemble" that appears in this standard's definition for both "objective data" and "historical monitoring data" (note that historical data may be used as objective data) in the standard's paragraph (b) has been defined in other standards as circumstances where the major workplace conditions which have contributed to the levels of historic exposure are no more protective than in the current workplace. OSHA's intent is to allow data reflecting past exposures to be used to predict current exposures only when the conditions of the earlier job were not more protective, i.e., employees were not better trained, work practices were not used more consistently, and no more supervision was present (reference 59 FR 40977, 29 CFR Parts 1910, et al., Occupational Exposure to Asbestos; Final Rule, August 10, 1994).
   
• The burden is ultimately on the employer to show that the objective data comply with the requirements of the standard. OSHA's intent is to allow employers the greatest possible flexibility in selecting methods used to determine employee exposures to chromium (VI), so long as the methods used are accurate in characterizing employee exposures (71 FR 10342).
   

Thank you for your interest in occupational safety and health. We hope you find this information helpful. OSHA requirements are set by statute, standards, and regulations. Our interpretation letters explain these requirements and how they apply to particular circumstances, but they cannot create additional employer obligations. This letter constitutes OSHA's interpretation of the requirements discussed. Note that our enforcement guidance may be affected by changes to OSHA rules. Also, from time to time we update our guidance in response to new information. To keep apprised of such developments, you can consult OSHA's website, as mentioned above, at http://www.osha.gov. If you have any further questions, please feel free to contact the Office of Health Enforcement at (202) 693-2190.

Sincerely,



Edwin G. Foulke, Jr.

[Reviewed; consistent with current policy 2/15/2008]