Measurement methods for continuous monitoring of the mass concentration of particulate matter (PM) frequently yield data which differ from standardized manual gravimetric methods. The data set from a I year measurement period at four sites in Austria was used to analyze the results from gravimetric (high volume sampling) and automated methods (TEOM(R) and beta-attenuation). Grouping of the data according to season (average temperature) and chemical composition (in particular nitrate) showed good agreement of the various methods for summer and even better for low nitrate content. Correction for nitrate from experimental data and also from modeled nitrate improved the agreement also for winter data and higher nitrate concentrations. At least for the situation in Central Europe adequate conversion factors can be derived from information about the nitrate content of PM between data based on different measuring methods. (C) 2004 Elsevier Ltd. All rights reserved.