Condensable suspended particulate matter, condensable SPM, is generated during the cooling process of flue gas by mixing with the atmosphere. Condensable SPM from stationary sources, such as power plants, waste incinerators and factories, is rather difficult to evaluate since dust sampling from exhaust gas is usually performed downstream of dust collectors, which are maintained at relatively high temperatures. In this study, in order to discuss the emission mechanism of condensable SPM from waste incinerators, model flue gas comprised Cd and Pb was produced by the sublimation of pure CdCl2 and PbCl2 in gas stream. Model flue gas was cooled in a diluter after separation of particulates by a bag filter kept at operational temperatures common to commercial plants. Particle size distribution of generated condensable SPM after a diluter was measured by a differential mobility analyzer (DMA). The composition of the model gases was determined based on our experiments carried out on fueled refuse derived fuel (RDF) in a laboratory-scale fluidized bed combustor. The effect of the CdCl2 and PbCl2, sublimation temperature, filtration temperature, and bag filter ash layering on the resulting particle size distribution of SPM was examined. The emission possibility of condensable SPM from solid waste incinerators is discussed based on experimental results and thermodynamic calculation. (C) 2007 Elsevier B.V. All rights reserved.