DOL Lowers Permissible Exposure Limit for Silica Dust

The U.S. Department of Labor on Tuesday announced that its Mine Safety and Health Administration issued a final rule that lowers the permissible exposure limit for silica dust. The rule lowers the PEL from 100 to 50 micrograms per cubic meter of air for a full-shift exposure. Mine operators are required to take immediate corrective actions when exposure exceeds the limit. In addition to reducing exposure limits, the final rule also requires mine operators to use engineering controls to prevent overexposure to respirable crystalline silica and use dust samplings and environmental evaluations ...