The formation of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and chlorobenzenes (PCBzs) in the combustion process was studied where the chlorine level and source were varied in an artificial waste. Different levels of organic chlorine (PVC) and inorganic chlorine (CaCl 2 ‚6H 2 O) were added to the fuel. The flue gas samples were analyzed for PCDDs/PCDFs and PCBzs. The following combustion parameters were measured during incineration: temperature in bed, in freeboard, and in cooling convector; air flows; SO 2 , CO 2 , NO, NO 2 , CO, O 2 , and particle concentrations in the flue gas. The results from this study indicate no correlation between the quantities of formed PCDDs/PCDFs and PCBzs in the combustion process and the level of chlorine in the fuel, when the chlorine level is below 1%. However, when the level of chlorine in the fuel exceeds 1%, an increased formation rate was noted. No distinction in the formation rate of the chlorinated micropollutants was noticed between the two different chlorine sources.