Our conclusion extends to coal dust, silica dust or a dust sample used to assess compliance with a reduced dust limit based on the silica content of the dust. (29 C.F.R. § 1910.1000, Table Z-3; 29 C.F.R. § 1926.55, Appendix A; 29 C.F.R. § 1915.1000, Table Z; 30 C.F.R. § 70.100; 30 C.F.R. § 71.100; 30 C.F.R. § 56/57.5001.)

In addition, we conclude that the inaccuracies of the MSHA and OSHA dust sampling and analysis systems at compliance levels are counter-productive to health protection. Inaccurate government systems interfere with accurate assessments of dust exposure risks, discourage companies from conducting their own sampling and analysis, and discourage advances in technologies that could improve measurement accuracy.

The major problems with agency dust assessment systems are:
• The regulatory dust limits are for health protection from “respirable” dust, limited to very small particle sizes (e.g., under 10 microns in diameter) that can reach the lungs. This concept was unanimously confirmed by 2014 testimony of academic, government and industry experts; see e.g., OSHA silica rulemaking record at www.osha.gov.

• The agencies do not confirm by lab analysis the lack of contamination by large particles on dust samples that add significantly to the sample weight and interfere with silica analysis. See U.S. Chamber of Commerce and National Mining Association comments and testimony of experts submitted to the OSHA silica rulemaking record, Docket No. OSHA-2010-0034 (January 27, 2014).

• MSHA’s new coal dust rule masks particle size issues by defining respirable as any dust collected by an “approved” sampler, ignoring its health protection purpose and encompassing the regulation of non-hazardous dust. Although the MSHA definition relies on the design of samplers to limit collection of large particles, they do not reliably conform to scientifically accepted lung penetration curves such as the American Conference of Governmental Industrial Hygienists.

• The agencies assume that the cyclone contained in the sampling equipment designed to collect small particle size dust works perfectly, but it does not. See comments from the U.S. Chamber of Commerce submitted February 11, 2014, OSHA-2010-0034-2259.

• As demonstrated by OSHA personnel testimony in administrative law judge proceedings from 2011-2014 and OSHA rulemaking testimony, the agencies assume they can visually examine samples for large particle sizes, but they cannot, since the human eye cannot see regulated particles or even 10 micron particles.

• Agency dust sample collection procedures often violate their own published warnings to not use certain pump calibration devices for many of their dust sampling pumps because of errors, resulting in improper pump flow rates.

• The agencies have a record of Proficiency Analysis Tests (AIHA round robin testing) demonstrating a wide range of results by their labs compared to commercial labs. (Comments of the U.S. Chamber of Commerce submitted February 11, 2014, OSHA-2010-0034-2259, p. 2.)

• The agencies insist on using a single shift sample to represent exposures to a long-term health hazard, even though single shift samples have been proven to be inaccurate representations of employee exposures. (U.S. Chamber of Commerce comments submitted February 11, 2014, OSHA-2010-0034-2259.)

• MSHA’s recent adoption of an instantaneous read-out sampler, based on vibration frequency changes caused by collected dust, fully eliminates both particle size examination capability and silica analysis, since the collected dust is not sent to a lab. As a result, MSHA enforcement of silica content reduced dust standards, using the new sampler, will rely on outdated, old silica analysis rather than current condition analysis, and examination for oversize, nonrespirable dust impacting the new sampler’s results will be impossible. (79 Fed. Reg. 24814, 24865, May 1, 2014.)

• The OSHA and MSHA labs have extensive, written lab procedures for weighing and analysis, but the procedures are easily bypassed and worthy of detailed case-by-case review to determine the validity of analysis, as demonstrated in recent depositions and administrative law judge cases. Among the ignored procedures are mandates to collect and/or analyze “bulk” samples for lab analysis, to determine the presence of minerals that interfere with silica sample X-ray analysis. (Comments from the U.S. Chamber of Commerce experts, submitted February 11, 2014, OSHA-2010-0034-2259, p. 2.)

• Routine lab analysis procedures include daily and per field sample analysis of “standards” that contain predetermined silica weights, but can record phantom results (excess above the standard’s actual weight), are not deducted from field sample compliance results obtained on the same day. Instead, MSHA and OSHA use a calculated error factor established over time that can “smooth” results.

• MSHA and OSHA adopted a regulatory definition of “accuracy” — plus or minus 25% of the true value, 95% of the time — to mask the inaccuracy of their sampling and analysis results, but they cannot meet even this unsupportable change to the English language. (Comments from Appendix 8 to the U.S. Chamber of Commerce submitted February 11, 2014, OSHA-2010-0034-2259, p. 2.)

We suggest that an independent study of government dust sampling and analysis procedures are needed to address the flaws summarized. Until improvements are implemented, OSHA and MSHA increasingly will find their alleged dust violations challenged, and likely rejected by judges relying on expert witnesses that understand and question the validity of the OSHA and MSHA process.


Henry Chajet, Brian Hendrix and Avi Meyerstein are shareholders at law firm Jackson Lewis P.C. Ross Watzman is an associate. All are members of the firm’s Workplace Safety and Health Practice Group.