A multi-nozzle (3-nozzle) geometry was examined for use in an inertial filter unit of a previously developed cascade air sampler consisting of 4-impactor stages (PM10/2.5/1/0.5) followed by a single- nozzle inertial filter unit (PM0.1) imbedded in a circular nozzle. The improved design allowed multiple samples to be obtained, thus allowing the analysis of multi-chemical particle components in a size range of 0.1–0.5µm. Technical data were collected for this new filter unit, and the findings were compared to corresponding data for a single nozzle inertial filter unit. Particles were collected from both types of air samplers with 1- and 3-nozzle inertial filter units, providing a detailed comparison between the 2 units. Total carbon analysis was used to determine the uniformity of the PM0.1 collected on a filter downstream from the inertial filter unit to compare differences between the nozzles of the 3-nozzle unit as well as those between the 1- and 3-nozzle units based on the chemical components. By adjusting the amount and uniformity of fibers in each inertial filter of the 3-nozzle unit, the separation performance was very close between 1- and 3-nozzle geometries with about a 5% less pressure drop for the 3-nozzle unit. Differences in the collected particle mass and the total carbon between the 3-nozzles were confirmed to be less than 10%. Deviations in the collected particle mass and the total carbon between 1- and 3-nozzle geometries were found to be less than 10%. Non-uniformity was observed for a larger particle mass loading for the 1-nozzle unit, while particles were collected uniformly for the 3-nozzle unit regardless to the extent of particle loading. These data together with the achieved lower pressure drop show that the novel multi-nozzle design has practical applicability, thus opening further possibilities for the chemical analysis of PM0.1 particle fractions.