New Edition of Mining Dust Control Handbook Released by NIOSH
NIOSH has published the second edition of the handbook Best Practices for Dust Control in Coal Mining (PDF). This document provides general information on engineering controls to be used in coal mining with the goal of limiting worker exposure to respirable coal dust. Overexposure to respirable coal dust can cause coal workers’ pneumoconiosis (CWP), the disease commonly known as black lung, which can be disabling or fatal in its severe form. Coal mine workers can also be exposed to respirable silica dust, which can cause silicosis, another disabling or fatal lung disease.
The prevalence of CWP greatly decreased in the 30 years following the passage of the Federal Coal Mine Health and Safety Act of 1969, which set the first respirable dust exposure limits in the U.S. coal mining industry. However, since 2000, data has indicated an increased prevalence of CWP and greater numbers of miners being diagnosed with the disease’s most severe form, progressive massive fibrosis. Consequently, the mining standard was amended in 2014 to reduce respirable dust exposure limits, require more aggressive sampling, and expand the CWP monitoring program. Originally published in 2010, NIOSH’s handbook has been updated in consideration of the increasing prevalence and severity of lung diseases associated with coal mining and the revised regulations.
NIOSH aims to control mine dust following the approach outlined by the traditional hierarchy of controls: elimination, substitution, use of engineering controls, use of administrative controls, and use of personal protective equipment. Since the nature of mining work typically does not permit the elimination or substitution of processes that generate mine dust, NIOSH’s handbook primarily focuses on engineering controls. The publication discusses controls ranging from those that have been long implemented in the coal mining industry to newer controls still being optimized. The publication also provides a general methodology for controlling respirable dust generation and worker exposures.
An additional hazard associated with coal mining is float coal dust, which settles out of the air onto the floors, roofs, and ribs of mine entries. It contributes to mine disasters when it is lifted into the air, typically by a methane gas explosion, causing a more violent coal dust explosion throughout the mine. NIOSH has recently conducted research into engineering controls that reduce the amount of coal dust that collects in mine entries, and the handbook covers these tools in addition to those dealing with respirable dust.
Finally, NIOSH’s handbook stresses the importance of continued use and maintenance of engineering controls after implementation in mines.
For more information and to download a PDF of the handbook, visit NIOSH’s website.