Simultaneously measure PM1, PM2.5, Respirable, PM10, and total PM size fractions. DustTrak Environmental Monitor 8543 is a data-logging, light-scattering laser photometer that enables simultaneous real-time aerosol mass readings of particulate matter. DustTrak air monitors use a sheath air system that isolates the aerosol in the optics chamber to keep the optics clean for improved reliability and low maintenance.