“…For example, they have been important instruments: in the study of ice nuclei Mason et al, 2015;Twohy et al, 2016), toward the understanding of outdoor fungal spore concentrations (Gosselin et al, 2016;Saari et al, 2015a;O'Connor et al, 2015b), to investigate the concentration and properties of bioaerosols from long-range transport (Hallar et al, 2011), in tropical aerosol Whitehead et al, 2010Whitehead et al, , 2016Huffman et al, 2012;Valsan et al, 2016), in urban aerosol Saari et al, 2015b;Yu et al, 2016), from composting centers (O'Connor et al, 2015b), at high altitude Gabey et al, 2013;Perring et al, 2015;Ziemba et al, 2016), and in many other environments (Healy et al, 2014;Li et al, 2016;O'Connor et al, 2015a). The same instrumentation has been utilized for a number of studies involving the built, or indoor, environment as well (Wu et al, 2016). As a limited set of examples, these instruments have been critical components in the study of bioaerosols in the hospital environment (Lavoie et al, 2015;Handorean et al, 2015) and to study the emission rates of biological particles directly from humans (Bhangar et al, 2016) in school classrooms (Bhangar et al, 2014) and in offices (Xie et al, 2017).…”