Chapter 4 Calibration and applications of low-cost particle sensors: a review of recent advances

Abstract

Particulate matter (PM) has been monitored routinely due to its negative effects on human health and atmospheric visibility. Standard gravimetric measurements and current commercial instruments for field measurements are still expensive and laborious. The high cost of conventional instruments typically limits the number of monitoring sites, which in turn undermines the accuracy of real-time mapping with insufficient spatial resolution. The new trends of PM concentration measurement are personalized portable devices for individual customers and the networking of large quantity sensors to meet the demand of Big Data. Therefore, low-cost PM sensors have been studied extensively due to their price advantage and compact size. These sensors have been considered as a good supplement to current monitoring sites for high spatial-temporal PM mapping. However, a major concern is the accuracy of these low-cost PM sensors. This chapter will introduce working principles of low-cost PM sensors, together with calibration methods and calibration metrics used in previous research to evaluate the performance of lowcost PM sensors. We will also introduce how these low-cost PM sensors have assisted pollution mapping in real-life applications. Finally, the challenges regarding the calibration and application of low-cost PM sensors have been discussed.