This European Standard specifies requirements relating to the construction, performance and methods of testing for membrane separation systems with a particle rating below 1 ïm, namely microfiltration (MF), ultrafiltration (UF), nanofiltration (NF) and reverse osmosis (RO) for drinking water installations inside buildings, intended to remove from the drinking water marginal concentrations of suspended and colloidal solids, microorganisms, organic molecules and/or to reduce the dissolved solids concentration and applies to systems with a minimum pressure of PN 10, connections between DN 15 and DN 100 and a maximum working temperature of at least 30 °C.This