In environments where excavation is used to break rock, airborne rock dusts pose respiratory health threats to workers. This includes mining with mechanical excavators which are common in industrial minerals as well as some tunneling operations. The purpose of this study is to compare characteristics of rock dusts generated by pick cutters at different wear conditions such that results could be used in the evaluation of proper bit management and dust suppression controls in the underground environment. The study included laboratory full scale cutting of concrete, limestone, and sandstone samples where each rock was cut with three conical picks at new, moderately worn, and fully worn stages of wear. Dust samples were analyzed to reveal the concentrations, mineralogy, particle shapes, and particle size distributions. The results show that for all rock types, the worn pick consistently generated the highest concentration of dust, all picks consistently generated dust containing quartz, and all three picks consistently generated dust particles of similar shapes. Additionally, although there are slight shifts in the particle size distributions between the various pick wears, all the particle sizes reside in the respirable range less than 10µm in aerodynamic diameter for all the rock types cut in this experiment.
