This standard specifies two methods for determining the water content in polyols (including polyether polyols, polyester polyols, and polymer polyols) used as raw materials for polyurethane. Method A is a manual coulometric method based on the Karl Fischer principle, applicable to most polyols, including colored samples; Method B comprises more automated approaches, specifically automatic coulometric and automatic Karl Fischer titration methods, with the latter offering higher sensitivity and requiring no calibration. The core instrument for performing the tests according to this standard is a Karl Fischer moisture analyzer, particularly titration systems equipped with coulometric and volumetric Karl Fischer functionalities, enabling precise measurement of trace moisture and providing critical quality control parameters for polyurethane production.