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MSHA News Release No. 98-0112
Mine Safety and Health Administration
Contact: Katharine Snyder
Phone: (703) 235-1452

Monday, January 12, 1998


The Mine Safety and Health Administration (MSHA) has announced a new enforcement strategy designed to better protect miners from black lung by requiring coal mine operators to take more prompt corrective action once an overexposure has been identified.

Beginning April 2, MSHA will base noncompliance determinations on the results of single full-shift dust samples taken by inspectors and issue a citation when any one full-shift measurement demonstrates that the applicable standard has been exceeded. Adopted as part of a campaign to eliminate black lung from the nation's coal mines, MSHA's new policy will replace the current practice of relying on the average of several inspector samples to determine noncompliance.

"This is another important step to protect the nation's coal miners from black lung," said Davitt McAteer, assistant secretary of labor for mine safety and health. "MSHA will require a mine operator to take corrective action to lower the concentration of respirable dust whenever a full-shift measurement by an MSHA inspector indicates noncompliance This will minimize the risk to miners of continued exposure to excessive dust levels."

Until now, even when an MSHA inspector found excessive dust levels for some occupations or work locations in a coal mine, corrective action was not required unless and until the average of several measurements exceeded the applicable standard.

MSHA is changing its respirable dust enforcement strategy based in part on the joint finding issued by the agency and the National Institute for Occupational Safety and Health (NIOSH) that a single, full-shift sample will accurately measure the average concentration of respirable dust to which a miner is exposed during the shift on which it was taken.

"Black lung has declined with better dust control in coal mines, but cases still occur," said McAteer. "Effective control of miners' exposure to respirable coal mine dust is critical because prevention is the only defense. The joint finding is based on sound science that has been rigorously scrutinized. Each episode of overexposure contributes to the health hazard of developing black lung disease."

Black lung disease, caused by overexposure to respirable coal mine dust, can impair lung function and even lead to heart failure. Moreover, black lung can progress even after the miner is no longer exposed to coal mine dust.

MSHA's respirable dust standard generally requires that coal miners' exposure to respirable coal mine dust be maintained at or below 2.0 mg per cubic meter, but the standard may be lower in some cases, for example when quartz--a silicosis hazard-- is present in the dust.

"A single-shift sampling strategy is the most practical enforcement approach that reasonably assures control of a miner's exposure so that adverse health effects are unlikely to occur," McAteer emphasized.

Federal mine safety and health law explicitly requires that the average dust concentration be continuously maintained at or below the applicable standard during each shift. This is consistent with standard industrial hygiene practice as applied by the Occupational Safety and Health Administration (OSHA) in general industry, and by MSHA in metal and non-metal mines.

The change in MSHA's inspector dust enforcement policy does not affect samples required to be taken by mine operators as part of the overall strategy to control respirable dust in coal mines.

Under the new enforcement policy, MSHA will continue to take multiple samples for each mechanized mining unit during a sampling shift, but any individual sample indicating overexposure will require corrective action.

The new policy is one of several recent MSHA actions reflecting recommendations by an Advisory Committee on the Elimination of Pneumoconiosis Among Coal Mine Workers. In developing the new joint finding and MSHA policy, MSHA and NIOSH also held several public hearings on the finding and policy in proposal form, and reviewed extensive written comments from the mining community.

The joint finding by MSHA and NIOSH and the new MSHA policy concerning respirable dust sampling appeared in the Federal Register December 31, 1997. The finding and policy also may be found on MSHA's Web Site at under Statutory and Regulatory Information, Federal Register Documents, Miscellaneous Notices.

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