ProPublica: In early 2011, after years of study, the Occupational Safety and Health Administration moved to reduce the permissible levels of silica dust wafted into the air by industrial processes like fracking, mining or cement manufacturing. The move came after years of public comment and hearings, and reflected emerging science about the dangers posed by even low levels of dust. OSHA predicted the rule would save 700 lives annually and prevent 1,600 new cases of silicosis, an incurable, life-threatening disease....