A field investigation into the characteristics and formation mechanisms of particles during the operation of laser printers and photocopiers

Indoor particle release from toner printing equipment (TPE) is a major health concern and has received wide attention. In this study, nine printing centers were randomly selected and three working phases were simulated, namely, non-working, normal printing/copying, and heavy printing/copying. The dynamics of the ozone (O-3), volatile organic compound (VOC), and particle emissions from TPE were determined by portable detectors. Results showed that particles, VOCs, and O-3 were indeed discharged, and particles and VOCs concentrations remained at high levels. Among them, 44% of the rooms represented high-level particle releases. Sub micrometer-sized particles, especially nanoparticles, were positively correlated with VOCs, but were inversely proportional to the O-3 concentration. Four elements, Ca, Al, Mg and Ni, were usually present in nanoparticles because of the discharge of paper. Si, Al, K, Ni and Pb were found in the submicrometer-sized particles and were consistent with the toner composition. The potential particle precursors were identified, which suggested that styrene was the most likely secondary organic aerosol (SOA) precursor. Overall, the use of the toner formulation and the discharge of paper attribute to the TPE-emitted particles, in which styrene is a specific monitoring indicator for the formation of SOA. (C) 2022 The Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V.

Automated summary

Indoor particle release from toner printing equipment is a significant health concern. This study investigated the emissions of particles, volatile organic compounds (VOCs), and ozone from the equipment. The results showed that particles and VOCs were discharged, and their concentrations remained high. Nanoparticles were positively correlated with VOCs and inversely proportional to ozone concentration.