This standard specifies a method for the determination of the mass of water soluble NO3-, SO42-, Cl-, NH4+, Na+, K+, Mg2+, Ca2+ in PM2,5 samples which can be used to comply with EU Directive 2008/50/EC. This standard describes a measurement method which comprises sampling of anions and cations as part of the PM2,5 particulate phase, sample extraction and analysis of anions and cations by ion chromatography. Alternately, cations, excluding ammonium can be analysed by inductively coupled plasma optical emission spectrometry (ICP-OES). This standard may be used at rural background monitoring sites that are in accordance with the requirements of EU Directive 2008/50/EC, and also at urban background sites and road sites. The described method was validated in field tests carried out at several European locations.