Experimental filtration processes were carried out to investigate the air flow resistance during separation of three types of wood dusts in a pilot-scale pulse-jet filter. Three types of dust were compared: dust from sanding pine wood, dust from sanding beech wood and dust from working particleboard. These dusts are characterized by different particle-size distribution. The resistance coefficient K-1 was determined for the filter fabric used in tests. Basing on the results of pressure drop across the filter measured during the experimental processes in condition of three levels of filtration velocity V-f (0.0405; 0.0484 and 0.0583 m s(-1)) the specific dust cake resistance coefficient K-2 was calculated. It value depends on the dust type and filtration velocity used. The lowest K-2 (20,085 s(-1)) has pine wood dust at filtration velocity 0.0484 m s(-1). While the highest value (28,925 s(-1)) was calculated at V-f = 0.0583 m s(-1) for dust from working of particleboards. (C) 2018 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.