The Dekati® Gravimetric Impactor (DGI) is a high sample flow rate cascade impactor for low concentration particle measurement applications. The DGI measures gravimetric particle mass size distribution of particles < 2.5 μm in five size fractions. Typical measurement applications of the DGI impactor include engine emission measurements, air quality studies and other low concentration applications where high sample flow rate is needed. The DGI collects size classified particles on Ø47 mm substrates that are analyzed gravimetrically or chemically after the measurement. The smallest particle size fraction is collected on a Ø70 mm filter.