Single gas permeation experiments results using neon, argon, nitrogen and methane are reported. From gas permeation experiments the characteristic parameters of the Knudsen and Poiseuille transport mechanisms were determined by means of an equation derived from the "Dusty-Gas" model. The experiments were performed at different temperatures from 303.15 to 323.15K, in order to study the temperature influence on those parameters. For PVDF and PCTE membranes the influence of the temperature on K, and B. parameters was not significant. Gas influence was also investigated for both types of membrane, a slight tendency of K, to decrease with increase in molar mass and a very slight tendency of B. to increase with increase in molar mass, although these trends were not fulfilled by neon gas. (c) 2008 Elsevier Ltd. All rights reserved.