Objectives: This study was conducted to assess the size characteristics of particulate matter (PM) generated during waste collection and sorting, and to assess the effect of the type of waste-handling activity on levels of coarse and fine PM. Methods: A portable aerosol spectrometer calibrated to 1.2 //min was used to monitor PM generated during four types of waste-handling activities. The types of PM measured included inhalable particulate matter (IPM), PM₁₀, respirable particulate matter (RPM), PM_2.5 and PM₁. Twenty-eight data sets with 3,071 subsets recorded every 6 sec were categorized according to occupational and environmen¬tal classifications, including type of waste-handling activity. An ANOVA was used to compare PM levels characterized by size. Significant variables with p-values <0.25 were included in a multiple regression model for predicting levels of each PM. Results: The average levels of PM₁₀ and PM_2.5 greatly exceeded the air-quality levels enforced by the Korean Ministry of the Environment. The highest PM_2.5 fine-particle levels monitored were during waste-transfer work, while the highest IPM and PM₁₀ coarse-particle levels monitored were during waste-sorting work. The type of waste-collection activity was the only factor that significantly affected both PM25 and IPM, accounting for 36% ( p =0.0034) and 40% ( p =0.0049), respectively, of the observed variations. None of the factors affected PM₁₀ or RPM levels. Conclusions: Waste-collection and Waste-transfer work may be associated with the generation of high levels of fine PM, which can be influenced by environ Workmental conditions such as traffic levels and the type of waste transport vehicle.(J Occup Health 2013; 55: 503–510)