The Evaluation of the Intercomparison Exercise for SO2, CO, O3, NO and NO2 - June 2007

In June 2007 in Ispra (IT), 9 AQUILA (Network of European Air Quality Reference Laboratories) laboratories and one laboratory of the World Health Organisations (WHO) Euro-Region met at an intercomparison 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. In terms of criteria imposed by the European Commission, 60% of the results reported by AQUILA laboratories were good both in terms of measured values and reported uncertainties. Another 37% of the results had good measured values, but the reported uncertainties were either too small (4%) or too high (33%). The comparability of results among AQUILA participants is satisfactory for O3, SO2, CO and NO measurement method, but the pollutant NO2 needs further improvements and harmonization programmes.JRC.H.4-Transport and air qualit