Module fabrication has always been treated as proprietary know-how. Systematic teaching and scientific study on module design and fabrication in academic journals are lacking. Small membrane modules consisting of 10-20 pieces of hollow fibers made simply for performance evaluation in laboratories normally cannot provide sufficient information for industrial applications because of the negligence of the effects of temperature change. different flow patterns and fiber variability. Thus a simple approach to fabricate lab-scale hollow fiber membrane modules with high packing density of 45-60%, which is around the level of commercial modules, by using commercially available standard parts was demonstrated. The detailed procedure of fabrication was described step by step. Verification tests show that the resultant lab-scale hollow fiber modules have high packing density of 49.3% and can withstand high pressure up to 500 psi with good separation properties. This know-how-based technique may provide a close linkage in terms of performance prediction, system modeling, and scaling-up between the lab-scale research and industrial-scale membrane systems for gas separation. (C) 2004 Elsevier B.V. All rights reserved.