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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 at https://www.osha.gov.
November 5, 2014
F. Stephen Masek
Masek Consulting Services, Inc.
23487 Sandstone St.
Mission Viejo, CA 92692
Dear Mr. Masek:
This is in response to your letter dated June 2, 2014, to the Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA). In your letter, you ask if asbestos regulations changed with respect to point counting of asbestos bulk samples. In addition, you point out that there may be worker air exposures to asbestos fiber above the OSHA permissible exposure limit (PEL) from disturbance of building materials having less than 1% asbestos as determined by point count.
This response is specifically for OSHA. There are 27 states and U.S. territories, including California, that have their own OSHA-approved occupational safety and health programs that enforce their own occupational safety and health standards that are required to be at least as effective as OSHA's, but may have different or additional requirements. A list of the State Plans and more information is available at https://www.osha.gov/dcsp/osp/index.html.
OSHA has not changed its regulations with respect to bulk asbestos analysis. The only sections of the OSHA standards for asbestos which have a requirement for bulk sampling and analysis are those which describe the procedure for an employer to rebut the presence of asbestos containing material (ACM) where it would otherwise be presumed asbestos containing material (PACM). PACM means thermal system insulation and surfacing material found in buildings constructed no later than 1980. The procedure can be found in each of the three regulations respectively, at General Industry 29 CFR 1910.1001(j)(8), Construction 29 CFR 1926.1101(k)(5), and Maritime 29 CFR 1915.1001(k)(5).
The OSHA construction regulation for asbestos states that an employer or owner may demonstrate that PACM does not contain more than 1 percent asbestos by having a completed inspection conducted pursuant to the requirements of AHERA (40 CFR Part 763, Subpart E) which demonstrates that the material is not ACM, or performing tests of the material containing PACM which demonstrates that no ACM is present in the material. Such bulk sampling shall be conducted by an accredited inspector or a certified industrial hygienist (CIH). The analysis shall be performed by persons or laboratories with proficiency demonstrated by current successful participation in an accreditation program such as National Voluntary Laboratory Accreditation Program (NVLAP), the American Industrial Hygiene Association (AIHA), or an equivalent nationally-recognized round robin testing program.
The methods used to rebut the presence of ACM in PACM include OSHA ID-191 (Appendix K in 29 CFR 1926.1101), EPA/600/R-93/116 or others which meet the accreditation requirements of the regulation. In the context of employer rebuttal of ACM, point counting may be used, but it is not specified nor endorsed by OSHA.
In response to your concern that there is a potential exposure risk to asbestos fiber in the air when there is a disturbance of building materials that contain asbestos at amounts less than 1%, OSHA agrees that there is only a small correlation between bulk content and air concentrations of asbestos. OSHA understands that disturbances of materials with less than 1% asbestos may generate fiber concentrations in the air in excess of PEL.
OSHA does not, nor has it ever, recognized a 1% content in bulk materials as a safe amount of asbestos. A content of 1%, or greater, does, however, trigger specific, enhanced requirements in OSHA asbestos, regulations. Several previous letters of interpretation have made this clear. (For example: OSHA Letter of Interpretation to Kurt Varga, November 24, 2003; OSHA Instructions, CPL 02-02-063, CH-1, Inspection Procedures for Occupational Exposure to Asbestos Final Rule 29 CFR Parts 1910.1001, 1926.1101, and 1915.1001, January 9, 1996, and CPL 2-2-63 (REVISED), Inspection Procedures for Occupational Exposure to Asbestos Final Rule 29 CFR Parts 1910.1001, 1926.1101, and 1915.1001, November 3, 1995).
The 1% level is not a risk-based limit. It is a practical level which was set using a number of factors that trigger specific work practices when found in thermal systems insulation, surfacing material and other asbestos containing materials. Those materials are known to produce significant fiber levels when handled without proper controls. The concentration of asbestos, the condition of the material, the vigorousness of activity and environmental variables, among others, contribute to the lack of correlation of asbestos content to air exposure.
The OSHA regulations for asbestos apply to worker exposure to asbestos fibers in the air. Any measurable content of asbestos in bulk sample triggers the OSHA regulations. Depending upon work practices, air concentrations of asbestos fiber are known to be significant even when the source material is less than 1% asbestos. OSHA regulations of asbestos is anchored in a quantitative risk-based measurement of worker exposure to asbestos fibers in the air. From the first permissible exposure limit set in 1971, through the current regulations promulgated in 1994, the aim of the agency has been to limit the airborne exposure level of workers.
The OSHA regulations are based upon measured air concentrations of fibers. The fundamental requirement is that employers must not expose employees to concentrations of fibers above the PEL which is 0.1 fibers per cubic centimeter of air. All other parts of the regulations are designed to assist an employer to carry out that responsibility.
In summary, OSHA has always recognized the hazard of worker exposure to asbestos fibers in the air. The presence of any amount of asbestos in a material which a worker may disturb triggers the OSHA asbestos regulations. They contain a variety of requirements that must be followed when any amount of asbestos is present. OSHA regulations require employers to provide a workplace having asbestos exposures below the PEL, which is 0.1 fiber/cc. An asbestos concentration less than 1% does not in any way absolve an employer from the responsibility to keep the air exposure below the PEL.
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 responses to new information. To keep appraised of such developments, you can consult OSHA's website at http://www.osha.gov.
David Michaels, PhD, MPH