Pulverized coal boilers, commonly used in the power and heat-generating industries, constitute one of the most important sources of fine particulate matter (PM) emitted to ambient air. The evidence on airborne PM and its public health impact is consistent in showing adverse health effects at exposures currently experienced by urban populations in both developed and developing countries [1]. The amount, size distribution, chemical composition, and harmfulness of coal fly ash depends on a number of factors such as coal type, composition, preparation method, boiler type and construction, combustion conditions, and the type and efficiency of the applied air pollution control devices. This paper summarizes and discusses the parameters affecting size distribution and trace element contents of fly ash particles emitted from the energetic combustion of hard coal in pulverized boilers equipped with electrostatic precipitators.