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Please note: As of January 20, 2017, information in some news releases may be out of date or not reflect current policies.

MSHA News Release: [06/20/2011]
Contact Name: Amy Louviere or Jesse Lawder
Phone Number: (202) 693-9423 or x4659
Release Number: 11-0941-NAT

US Labor Departmentís MSHA publishes final rule for rock dust

Standard strengthens minersí protections, minimizes potential for coal dust explosion

ARLINGTON, Va. The U.S. Department of Labor's Mine Safety and Health Administration today announced that a final rule will be published June 21 in the Federal Register on the maintenance of the incombustible content of rock dust. The rulemaking came about as a result of the agency's review of accident investigation reports of mine explosions in intake air courses that involved coal dust, as well as the National Institute for Occupational Safety and Health's report "Recommendations for a New Rock Dusting Standard to Prevent Coal Dust Explosions in Intake Airways," which can be viewed at

"This rule is an important next step in the Labor Department's efforts to keep our miners safe," said Secretary of Labor Hilda L. Solis. "Inadequate rock dusting can increase the potential for explosions that destroy mines, lives, families and communities, and we must minimize that potential."

An emergency temporary standard was issued in September 2010, and the final rule maintains the same requirements as the ETS. The rule requires mine operators to maintain the percentage of incombustible content of the combined coal dust, rock dust and other dust at 80 percent in all accessible areas of underground bituminous coal mines, as well as an additional 0.4 percent for each 0.1 percent of methane where methane is present in any ventilating current. The final rule, like the ETS, increases the total incombustible content for all areas of the mine, other than return air courses, from 65 to 80 percent.

"MSHA responded quickly to the NIOSH report, which contained new scientific evidence that called for an improved standard for rock dusting," said MSHA Assistant Secretary Joseph A. Main. "We are committed to enforcing this important standard that ultimately will save lives, and we expect mine operators to act quickly to reduce the threat to those mining coal underground."

For a video overview of the danger of un-neutralized coal dust in mine explosions, visit The final rule can be viewed at