Research conducted by Dr. E. Lee Petsonk, of NIOSH has established that despite a 1973 dust control law, which required dust levels in mines to be kept below a 2 milligram per cubic meter concentration, younger miners are still contracting black lung disease.
Additionally, the study found a surprisingly high number of surface coal miners are contracting black lung.
Researchers suggest the study's results could be explained either by operators failing to meet the 2mg requirement or by the possibility that 2mg is still too high of a concentration.
The U.S. Mine Safety and Health Administration (MSHA) has meanwhile proposed a package of dust control regulations to increase protection of miners.
MSHA is holding six public meetings about the proposed plans which it says are part of the agency's comprehensive program to improve safety and health performance in the mining industry.
The proposed rules cover verification of coal mine dust control plans and the method used to determine respirable dust in coal mines.
"With these two actions, we are moving toward better control of respirable dust in the mines," said Dave D. Lauriski, assistant secretary of labor for mine safety and health. "Our goal is to send every miner home safe and healthy at the end of every working day."
One of the proposals is for MSHA to cite a coal operator for exceeding coal dust concentrations based on a single sample, updating a 32-year-old practice that called for averaging samples taken over multiple shifts. This means one or more shifts can be exposed to dust concentrations that exceed the 2-milligram limit while the average is still below the limit. This means each sample will stand on its own.
MSHA is also proposing to assume responsibility for all underground compliance dust sampling. Under current rules, mine operators take most samples required to determine compliance with federal standards designed to prevent black lung.
The proposal will eliminate the requirement for compliance sampling by underground coal mine operators, but they will still need to collect samples to verify the adequacy of dust control measures specified in their ventilation plans.
