This document describes a test method for laboratory evaluation of possible adverse effects of water treatment membrane elements and modules on drinking water quality. In principle it is applicable to microfiltration, ultrafiltration, nanofiltration, reverse osmosis and electrodialysis modules for use in the treatment of public water supplies and of water inside buildings. NOTE Such devices can vary considerably in design and operation and hence some modification of the procedures can be required. Evaluation of the efficiency of the membrane filter in removing contaminants from the treated water is not included.