Progressive massive fibrosis in a zinc miner.

The diagnosis of progressive massive fibrosis (PMF) is traditionally associated with exposure to coal dust. Since the legislation of better control of mine dust, the incidence of PMF has declined significantly. Clinicians who are not regularly involved in the medical care of coal workers may have limited knowledge of this incapacitating problem. Physicians are reminded that PMF is a complex process that can occur after exposure to mixed respirable particles other than coal dust.