Optical particulate matter sensors in PM2.5 measurements in atmospheric air Marek Badura, Piotr Batog, Anetta Drzeniecka-Osiadacz and Piotr Modzel E3S Web Conf., 44 (2018) 00006 Published online: 03 July 2018 DOI: 10.1051/e3sconf/20184400006