Performance evaluation of conventional type conductive cooling continuous flow compact water-based CPC (Hy-WCPC)

In this study, a water-based compact handheld condensation particle counter (Hy-WCPC) is developed and its performance is evaluated. The Hy-WCPC is a small and light water-based CPC and the operating principle is the same as the conventional continuous flow conductive cooling alcohol-based condensation particle counters (CPC). This study presents the particle material dependent Hy-WCPC cut-off sizes and the particle concentration counting linearity between the Hy-WCPC and electrometer by generating silver, sodium chloride, zinc and paraffin particles. Moreover, the comparison between the Hy-WCPC and commercially available ultrafine CPC (TSI 3776) for ambient airborne particles is presented. The cut-off sizes of the Hy-WCPC for silver and paraffin particles are 3.61 nm and 5.30 nm, respectively. For sodium chloride and zinc particles, the Hy-WCPC lower detection limit is achieved less than 4 nm. Moreover, the particle concentration counting linearity between the Hy-WCPC and electrometer is presented. The excellent particle number concentration counting linearity agreement between the Hy-WCPC and electrometer is shown for the laboratory generated particles. Also, the particle concentration counting linearity between the Hy-WCPC and the TSI 3776 for outdoor ambient airborne particles is shown. The reasonable agreement between the Hy-WCPC and the TSI 3776 was obtained. In the long-term measurement of outdoor ambient airborne particles for 7 days, this agreement had been maintained, however, after 7 days, the TSI 3776 did not operate properly due to the high humidity, while the Hy-WCPC was operating without the problem.