Read the report here. CHARLESTON, W.Va. -- The Obama administration used appropriate scientific studies and analysis when it proposed to toughen the limits on coal dust to fight a resurgence of deadly black lung disease, a federal government audit made public Friday concluded.A congressionally mandated review by the U.S. Government Accountability Office supported the federal Mine Safety and Health Administration proposal, dismissing coal industry complaints that challenged MSHA's evidence and methodology.In a 24-page report, the GAO said key scientific studies support MSHA's conclusion that tightening the dust limit would reduce miners' risk of getting black lung. The GAO review said research used by MSHA included "reasonable steps" to minimize the impact of any limitations in their data."Opponents of the proposed rule attacked the science, but the study they called for shows the science to be sound: The proposed rule would reduce coal miners' risk of developing black lung," said Rep. George Miller of California, the ranking Democrat on the House Committee on Education and the Workforce.Sen. Jay Rockefeller, D-W.Va., said the report "confirms how critical MSHA's new rules will be in protecting miners' health."Completion of the GAO report frees MSHA to finalize the rule, but agency officials on Friday offered no timeline for when they would do so."We are pleased that the GAO has completed its study, and its conclusions validate the work MSHA has pursued to update a standard that will ultimately save lives in the mining industry," said MSHA chief Joe Main. "Black lung disease devastates miners, families, and communities, and MSHA is committed to addressing the underlying causes of that dreaded illness."The United Mine Workers union declined comment on the GAO findings. UMW officials have generally supported the MSHA proposal, but are upset that it would still allow most dust-sampling to be done by mine operators.Black lung, or coal workers' pneumoconiosis, is an irreversible and potentially deadly disease caused by exposure to coal dust.In 1969, Congress made eliminating black lung a national goal, with a law that required mine operators to take steps to limit exposure. The law greatly reduced black lung among the nation's coal miners.Scientists have found, though, that black lung is on the rise again. Researchers have warned of a doubling of black lung rates since 1997, and of alarming incidence of the disease among younger miners whose entire careers took place under the 1969 law's dust limits.In West Virginia, more than 2,000 coal miners died of black lung between 1995 and 2004, second only to Pennsylvania, with 4,234 black lung deaths during the same period, according to government data. Nationwide, more than 10,000 miners died from black lung during those years.A joint investigation by National Public Radio and The Center for Public Integrity reported in July on the resurgence of black lung and, with additional reporting by The Charleston Gazette, documented widespread cheating by mining companies on dust samples and inaction by federal regulators over the past quarter-century to address the problem.Two years ago, MSHA proposed new rules based on such recommendations. Among other steps, the MSHA proposal, issued in October 2010, would reduce the legal limit for dust in underground mines from 2.0 milligrams of dust per cubic meter of air to 1.0 milligrams of dust per cubic meter of air. A Labor Department advisory commission recommended the change in 1996, and the National Institute for Occupational Safety and Health has been urging since 1995 that the limit be tightened.Industry officials argue that recent increases in black lung rates are a regional problem and don't require a new nationwide rule. On Friday, the National Mining Association said it is "very disappointed" that the GAO did not review more recent black lung incidence data that became available after MSHA published its proposal. However, the GAO report itself indicates the office examined a NIOSH report that was published in April 2011 and included that more recent data.Carol Raulston, as spokeswoman for the industry group, said the GAO's review of that more recent data "lacks specificity, which makes it impossible to ascertain what their review fully considered, the level of detail employed and the analytic methodology they used in reaching their conclusion."Late last year, Republican House members -- including Appropriations Chairman Hal Rogers, R-Ky., and subcommittee Chairman Denny Rehberg, R-Mont. -- slipped into MSHA's current year budget a provision that blocked the new black lung rules until the GAO completed an analysis of the MSHA plan. Last month, House Republicans sought to extend their hold on the rule.In a Friday statement, House Education and the Workforce Chairman John Kline, R-Minn., indicated he remains unsatisfied with the MSHA proposal and called on the agency to bring together industry and labor officials to work out a deal."A responsible, comprehensive solution can be advanced if all stakeholders come to the table and work together," Kline said.In late June, though, Kline and other Republican committee members voted down a procedural move by Miller aimed at pledging that the committee would move some sort of mine safety legislation -- perhaps including black lung language -- before the end of the year."Despite mounting evidence of the dangers of black lung disease, Republicans in the House continue to try to block these safety improvements," said Rockefeller, whose separate mine safety bill includes a mandate for tougher black lung protections. "We must act now, before we lose more West Virginia coal miners to this disease."Reach Ken Ward Jr. at firstname.lastname@example.org or 304-348-1702.