Abstract: An apparatus for cleaning the air discharged from an agricultural harvester. A separation housing has inlet and outlet ends. The inlet end includes an upper chute, a lower chute, and a separation wall therebetween. The lower chute extends from the inlet end to a clean air discharge intermediate the inlet and outlet ends. Air entering the lower chute is relatively clean, and is discharged to the atmosphere through the clean air discharge. Air entering the upper chute is relatively dirty, and is routed through the upper chute to a separation chamber having an upper input end, a lower output end, and a downwardly inclined passageway extending therebetween. Small particles and dust precipitate from the air and collect on the floor of the passageway. Harvester movement urges the particles and dust to exit from the output end dropping onto the ground, and clean air exits directly therefrom into the atmosphere.