The proposed rule includes halving the permissible limit for miners’ exposure to respirable coal mine dust, tighter dust control plan verification criteria, and the use of new technology—continuous personal dust monitors—to provide real-time measurements of miners’ exposures. MSHA also would require samples to be collected over a full shift to address extended work shifts, redefine normal production for compliance sampling purposes at levels far in excess of those in use today, require additional medical surveillance examinations for miners, and, as discussed below, provide for the use of a single, full-shift sample to determine compliance. Finally, the proposed rule would implement recommendations from a 1995 National Institute for Occupational Safety and Health (NIOSH) report, as well as a 1996 secretary of labor’s dust advisory committee report. 

This proposed rule, issued on October 19, 2010, which MSHA says is necessary to protect miners from contracting coal workers’ pneumoconiosis, raises the broader question of how to ensure agency regulations are based upon sound science.  This question was highlighted when, earlier this year, 45 members of the United States House of Representatives sent three studies to MSHA questioning the data underlying its proposed rule. The representatives had asked MSHA to re-open the comment period. MSHA denied their request, asserting that the three studies did not present any new scientific data or conclusions. 

The University of Kentucky released a new study in June. Based on analyzing more than 600 single-shift samples collected using a continuous personal dust monitor, the researchers found that “the variability associated with single-shift samples will be higher than the variability used to develop the proposed standard.” Thus, the new study raises the distinct possibility that many mines may face non-compliance determinations improperly, even when they are in full compliance with the proposed limits. On July 22, members of the House sent this study to MSHA and asked it to re-open the comment period on the proposed rule. 

Meanwhile, on August 1, Sen. Jay Rockefeller, D-W.Va., introduced the Black Lung Health Improvements Act of 2013. Although this bill does not require a specific new dust limit, it would require MSHA to finalize its proposed tighter dust limits within the next six months. Sen. Rockefeller also sent a letter to President Barack Obama pressing his administration to push ahead with new regulations aimed at ending black lung disease, noting that NIOSH reports warn of a resurgence of black lung. For example, he wrote, “Following the Upper Big Branch mine disaster, we learned that 17 of the 24 victims had black lung, and that, of the seven who did not show signs of the disease, four had anthracosis, a lung condition that can be linked to black lung disease.” (Twenty-nine miners were killed and two were injured in the April 5, 2010, incident.) He added, “[T]his disease is back and will not go away unless we make it a priority and act.” According to Rockefeller, while the delay in setting a tougher dust exposure limit was partially due to a statutory mandate to review the science underlying the proposed legislation, the resulting Government Accountability Office report has been available for nearly a year. 

Putting aside MSHA’s denial of the members of the House and Rockefeller’s requests, many believe MSHA has a legal obligation to re-open the comment period to consider the new University of Kentucky study. The Federal Mine Safety and Health Act of 1977, section 101(a)(6)(A), requires that MSHA base mandatory standards on “research, demonstrations, experiments, and such other information as may be appropriate” and consider “the latest available scientific data in the field.” According to a National Mining Association (NMA) official, the study “clearly presents new data and conclusions that were not considered by MSHA at the time the proposed rule was published.” 

Although MSHA is not required to consider every possible alternative, if it were to finalize this rule without examining all available data and scientific research, it may invite a successful legal challenge. 

Watzman is an associate with Jackson Lewis LLP, and is located at the Denver office. He can be reached at