关键词：大气；室外大气；空气污染
摘 要：Between September 18th and October 13th, 2012, National Institute for Occupational Safety and Health (NIOSH) researchers and the Silica/Milling-Machines Partnership coordinated by the National Asphalt Pavement Association (NAPA) conducted field testing of a local exhaust ventilation system (LEV) on a Roadtec RX600e cold milling machine. The tests included ten days of air sampling across seven different highway construction sites in Indiana. At each site, full-shift personal breathing zone samples for respirable crystalline silica were collected from the operator and ground man during the course of normal employee work activities of asphalt pavement milling.