#the current silica exposure limit for miners - whose occupational safety falls under the purview of the MSHA - is double what it is

[girderednerve]

The proposed crackdown on silica follows a fraught history of the mine safety agency's decades of failure to protect miners from the toxic dust. The proposal also overlooks a history of overexposure at coal mines.

Again, this downplays the need and justification for action.

The rule notes that 93% of silica dust samples have been in compliance with existing silica dust limits since 2016. But the remaining 7% of samples amount to 5,300 instances of excessive exposure to the dust based on the newly proposed limit, according to MSHA data analyzed by Louisville Public Media and Public Health Watch.

In the 30 years leading up to 2016, agency data analyzed by NPR and Frontline found 21,000 excessive silica dust samples based on the existing limit. More than twice that many dust samples — 52,000 — exceeded the newly proposed limit.

This means that coal miners worked amid dangerous levels of silica dust — which is easily inhaled, easily lodges in lungs and can lead to severe disease and death — tens of thousands of times in 30 years.

During those three decades, the risk of silica dust exposure increased, as mining consumed the thickest coal seams, leaving thinner seams embedded in rock. Cutting those thinner seams generated more fine silica particles.

Also, during that period, the agency did not respond effectively to the threat.