Broken pellets and fines are produced when pellets are handled. The resistance to air flow was measured for clean pellets and for pellets mixed with 1-20% broken pellets (fines). A pellet diameter was 6 mm. The lengths ranged from 6 to 12 mm. Clean pellets were defined as particles that remained on a 4 mm screen. A typical sieve analysis showed 30% of the mass of particles that passed through the 4 mm screen was smaller than 1 mm. The airflow rates used in the experiment ranged from 0.004 to 0.357 ms(-1). The corresponding pressure drop ranged from 1.9 to 271 Pa m(-1) for clean pellets, from 4.8 to 1100 Pa m(-1) for 10% fines content, and from 7.9 to 1800 Pa m(-1) for 20% fines content. Coefficients of Hukill and Ives' equation were estimated for clean pellets and a multiplier was defined to calculate pressure drop for pellets mixed with fines. (C) 2010 Elsevier Ltd. All rights reserved.