In February, NIOSH researchers confirmed what Scott Laney, an agency epidemiologist, described to National Public Radio as “the largest cluster of progressive massive fibrosis ever reported.” The cluster of more than 400 cases was discovered in a region that encompasses parts of Virginia, West Virginia, and Kentucky.  Progressive massive fibrosis, the most severe form of coal workers’ pneumoconiosis or black lung disease, was previously thought to be nearly eradicated due to improvements in working conditions in coal mines following implementation of the Federal Coal Mine Health and Safety Act of 1969. Incidence of all forms of black lung declined for thirty years after passage of the Act, which mandated stricter controls for coal mine dust, and then began to rise in the early 2000’s. Possible reasons for the increase include thin-seam mining, for which the protections in the Act may be inadequate, and longer work shifts. Information about black lung from several sources is presented below.