See check list in annex .
Sources are national emission inventories and measurement programmes in participating countries.
Sulphur compounds, nitrogen compounds, volatile organic compounds, ozone and heavy metals and persistent organic pollutants. All data received have a quality control check. For monitoring, interlaboratory tests of chemical analyses. Questionnaires to collect detailed information on monitoring sites, sampling equipment, methods for chemical analysis, as well as local quality assurance procedures. Atmosphere Emission Inventory Guidebook published to harmonize the methods used for emission estimates.