Portable multilateral measurement system employing Optical Particle Counter and one-stage Quartz Crystal Microbalance to measure PM10

Abstract

Air pollutants can cause a variety of environmental and health problems, and several epidemiological and clinical studies have investigate the association of diseases with air pollution. Air pollutants include fine particles and ultrafine particles, which show complex aspects depending on time and space. Therefore, a portable system for measuring fine particles is required. In this study, we developed a portable system to measure the number concentration, mass concentration, and effective density of PM10, which are important measures of fine particles. Current devices used to measure the effective density of particles are either large or only able to measure target particles at the nanoscale. In this study, an Optical Particle Counter (OPC) and a one-stage Quartz Crystal Microbalance (QCM) impactor were used to compose a PM10 multilateral measurement system to calculate the effective density of PM10. OPC is a small device that measures the number concentration of particles, and the QCM impactor measures the mass concentration of particles. Currently available QCM impactors for particle measurement are large devices. Therefore, we miniaturized it in the form of a one-stage impactor. The QCM was installed on an impaction plate to collect the particles. Through the developed system, the number and mass concentrations of input particles were simultaneously measured, and their effective density was calculated using the measured concentrations. Finally, outdoor air monitoring was performed, and the obtained measurements were validated by comparing them with the measurements of reference devices. A difference of 4.7% and 11% were obtained for mass and number concentrations, respectively. Therefore, the effective density of PM10 was successfully calculated.