This work aims at validating and extending the applicability of an existing correlating equation for predicting pressure drop through packed beds of spheres. A new set of data points out its use for bed geometric aspect ratio D/d(part) in the range 3.8-14.5, in the case of dense packings. The case of loose packings is also discussed using literature data. As a conclusion, a con-elation is proposed for predicting pressure drops through fixed beds of spheres (dense and loose packings) for large ranges of Reynolds numbers (similar to 10 < Re-part < similar to 2500) and of geometric aspect ratio (similar to 3.5 < D/d(part) < 40-50). (c) 2006 Elsevier B.V. All rights reserved.