EC harmonization programme for air quality measurements : the evaluation of the interlaboratory comparison exercise for SO2, CO, O3, NO and NO2 19.- 22. October 2009

From the 19th to the 22nd of October 2009 in Ispra (IT), 8 Laboratories of AQUILA (Network of European Air Quality Reference Laboratories) met at an interlaboratory comparison exercise to evaluate their proficiency in the analysis of inorganic gaseous pollutants covered by European Air Quality Directives (SO2, CO, NO, NO2 and O3). The proficiency evaluation, where each participant's bias was compared to two criteria, provides information on the current situation and capabilities to the European Commission and can be used by participants in their quality control system. On the basis of criteria imposed by the European Commission, 85% of the results reported by AQUILA laboratories were good both in terms of measured values and reported uncertainties. Another 14% of the results had good measured values, but the reported uncertainties were either too high (6%) or too small (8%). The comparability of results among AQUILA participants is satisfactory for O3, CO and NO measurement methods. This is not the case for SO2 and NO2 which comparability in the present exercise is not satisfactory with respect to the settled quality criteria.