Main Article Content
In this study, mass and number concentrations of PM2.5 in the ambient air during open burning season in Chiang Mai, Thailand was measured and described. The monitoring station was placed and field evaluated in Research Unit of Applied Electric Field in Engineering, Rajamangala University of Technology Lanna, Doi Saket District, Chiang Mai Province, Thailand during 1 – 15 April, 2019. The PM2.5 mass and number concentrations were simultaneously measured by the DustTrak model 8533 and the Condensation Particle Counter (CPC) model 3750, respectively. The field study results showed that the trend of the number concentration of PM2.5 measured by the CPC agreed to within small differences with the mass concentration of PM2.5 measured by the DustTrak. The maximum, minimum and average PM2.5 mass concentrations measured by DustTrak that average over the measurement period was about 180.33 µg/m3, 42.13 µg/m3 and 101.71 µg/m3, respectively, and the maximum, minimum and average PM2.5 number concentration measured by the CPC that average over the measurement period was about 22,460.94 particles/cm3, 4,550.39 particles/cm3 and 11,517.39 particles/cm3, respectively. Finally, the relationship and the proportion between the mass and number concentrations of PM2.5 obtained will be beneficial for further planning, prevention and monitoring of impacts on human health and the environment.