A Study of Respirable Silica in Underground Coal Mines: Particle Characteristics

Respirable crystalline silica is now considered to be a major culprit of resurgent lung disease among US coal miners—especially in central Appalachia—though questions remain regarding the specific circumstances around exposure it. As part larger investigation dust 15 mines, recent study examined content both respirable mine samples and generated laboratory from primary source materials (i.e., rock strata dusting products). It concluded that being drilled for roof bolting or cut along with most significant many which consistent expectations based on other scattered datasets. However, little information available characteristics particles might important understanding risks better. In current study, represents another aforementioned scanning electron microcopy energy dispersive X-ray spectroscopy (SEM–EDX) were used analyze size surface condition degree surface-associated clay) 1685 identified 58 samples. The results indicated typically finer locations nearby drilling cutting activities than it within mine, but Central Appalachian mines not necessarily regions. An analysis particle surfaces revealed often does occur as “free”, high-purity particles. Rather, there can range occurrences including having thin “occlusion” layer clay, agglomerates also contain types clays, even ingrained such coal.