Abstract
A new design for a cascade impactor is presented. Particulate material is collected at four impaction stages on two standard 1″ x 3″ glass microscope slides, with two deposits on each slide. The deposits can be spread out during collection by using an external slide movement mechanism. A 1″ diameter filter follows the impaction stages. A calibration nomograph is presented. Results obtained using this calibration are in good agreement with the results obtained by direct sizing of simultaneously drawn membrane filter samples.