Error analysis for emissions measurements with cascade impactors

It is noted that cascade impactors are used as sampling systems with particle size dependent fractionation. The fractionations obtained are analyzed gravimetrically or chemically. The paper reports on factors causing errors in this procedure. Attention is given to the differences between an ideal impactor as assumed when processing accumulated data, and the conditions in an actual impactor. Areas discussed include error analysis in fractionation and error analysis in particle mass determination.