The U.S. Department of Labor's Mine Safety and Health Administration (MSHA) has published a Request for Information (RFI) in the Federal Register seeking data on economically and technologically feasible methods to protect miners' health from exposure to quartz. The RFI includes an examination of an appropriately reduced permissible exposure limit, potential new or developing protective technologies, and/or technical and educational assistance. The Request for Information was published in the Federal Register on August 29, 2019.
Quartz accounts for the overwhelming majority of naturally occurring crystalline silica and is present in varying amounts in almost every type of mineral. Since mechanized mining and milling operations generate large amounts of dust, miners may become exposed to elevated levels of respirable quartz.