Six types of alumina with different particle size distributions have been tested for breakage in a plant-scale transport rig. Acoustic chemometrics is used to monitor the powder breakage during pneumatic transport. This is a non-invasive on-line monitoring technique. The correlation between the acoustic signals and the degree of powder comminution is investigated. By relating the acoustic information to dust fractions from the process, we assess the possibility of predicting powder breakage during transport, based on acoustic sensor technology and multivariate data modeling. (C) 2003 Elsevier Science B.V. All rights reserved.