Fluid dynamic gauging (FDG) has been used to study the kinetics of the cleaning, from various solid surfaces, of polymer layers representative of polymerization reactor foulants. Currently, solvents such as methylethylketone (MEK) are used for cleaning and it is desired to replace this with aqueous systems with less severe environmental impact. Laboratory-prepared samples of two polystyrene co-polymers and samples prepared in an industrial pilot plant were treated with two alkaline solutions, sodium hydroxide (NaOH) and sodium metasilicate, with an aqueous commercial cleaning agent (TPU) and with the organic solvent MEK. Single and composite layers were studied, and a variety of outcomes observed. The simple alkalis swelled the polymers but did not clean: MEK and TPU swelled and then cleaned off both laboratory films, the mechanism varying between cohesive breakdown and adhesive detachment for different polymer/solvent combinations. One pilot plant material behaved as its laboratory analogue, while another, which was not tested in the laboratory, left a residual film on the surface. Experiments on composite layers exhibited a rich diversity of behaviours which could be modelled as combinations of single film characteristics. (c) 2005 Elsevier B.V. All rights reserved.