This European Standard is one of a series dealing with products and systems for the protection and repair of concrete structures. It specifies a method for determining the resistance to water absorption of repair products and systems, as defined in prEN 1504-3 1). The method is based on measuring the increase in weight due to capillary absorption of water over a fixed time interval. The weight of water absorbed is expressed as a coefficient, indicating the tendency of the specimen to imbibe water by capillary action without external pressure applied. 1) Under preparation.