Organic substances that migrate from products containing such substances have, when used in contact with water intended for human consumption, the potential to cause health concerns for consumers. The potential health effects of these chemicals are assessed in three stages as follows: a) preparation of migration waters by exposing a portion of the material to water under controlled conditions; b) analysis of the migration waters; c) toxicological assessment of the identities and concentrations of the substance detected. The analysis of organic substances present in migration waters can involve two different types of analytical methods as follows: a) a screening method, which allows a variety of substances to be detected and a semi-quantitative assessment to be made of their concentrations; b) accurate quantitative methods for the determination of specific target substances known to be present in the chemical formulations of the materials. This standard prepared by CEN/TC 164/WG 3 "Effects of materials in contact with drinking water" describes the analytical procedures based upon gas chromatography and mass spectrometry (GC-MS) used to screen migration waters for organic substances derived from finished products such as pipes, protective coatings, membranes, etcetera. This method is suitable for migration waters from all products that can potentially release organic chemicals into water when they are used in contact with water intended for human consumption, and which are the subject of an application for approval by the national regulatory body. It may be one of several methods that form part of the overall approval process. The method may also be used as part of an approval audit process. The method does not provide accurate quantitative results and other analytical methods are recommended for accurate quantitative determination of specific target substances. As a national mirror committee, NA 119-07-09-01 UA " Europäische Prüfverfahren zur trinkwasserhygienischen Eignung von Werkstoffen (Supporting Standards, Mandate M/136)" ("European test methods for the suitability for drinking water hygiene of materials (Accompanying standards, mandate M/136")) at DIN Standards Committee Water Practice (NAW) was intensively involved in preparation of this standard.