1. Identifying and classifying zones and agglomerations Edward Roekens Flemish Environmental Agency

2. 2 Method of zonation 2004 Methodology followed Long time-series of measurement data for SO 2, NO x, and Pb (from 1978) and for PM10 (from 1996) Principals To determine the agglomerations and zones with an important number of citizens: quantity in combination with population density

3. 3 Principles of zonation Principals Areas with similar air quality are grouped in 1 zone (e.g. 10 urban zones in Flanders with more than 50.000 inhabitants but less than 250.000) have the same ozone, NO x, and PM10 issues Usually the zones are determined independent from the pollutant, but exceptions are possible (e.g. local influences of industrial activities: SO 2 in Wezel Present and future strategies of monitoring network and derived design

4. Air quality zones in Belgium

5. 5 Zonation SO 2, NO 2, PM10, Pb Code zoneZoneArea (km²)Inhabitants BEF01SAntwerp harbour 22250 000 BEF02AAntwerp agglomeration 174550 000 BEF03SGhent canal zone 11745 000 BEF04AGhent agglomeration 136370 000 BEF05SCities > 50000 inhabitants 786750 000 BEF06SRest of Flanders12.1264 250 000

6. 6 Zonation, 1st Daughter Directive All pollutant zones Agglomeration Antwerp and Ghent >250 000 inhabitants Cities > 50 000 inhabitants Large industrial zones: Antwerp harbour, Ghent (canal zone) Rest of Flanders

7. 7 Zonation, 1st Daughter Directive One polluent zones Lommel: SO 2 non-ferrous Beerse: Pb non-ferrous Hoboken: Pb non-ferrous

8. 8 Zonation CO, benzene, ozone, PAHs All polluant zones Agglomeration Antwerp an Ghent >250 000 inhabitants Cities > 50 000 inhabitants Big industrials zones: Antwerp harbour, Ghent (canal zone) Rest of Flanders Or simplified zonation: see blue (BEF19S)

9. 9 Zonation heavy metals Zonation for Pb, As, Cd and Ni zones Agglomeration Antwerp and Ghent >250 000 inhabitants Large industrial zones: Antwerp harbour: refineries Ghent steel industry Rest of Flanders Microzones Hoboken: (Pb), As, Cd Beerse: Pb, As, Cd Genk: Ni, (Cd)

10. 10 Vegetation and natural ecosystem 20 km from agglomerations 5 km away from other important sources No such places in Flanders However critical levels SO 2 20 µg/m³ NO x 30 µg/m³ Respected on sample sites of acid deposition network

11. 11 Supplementary methods of zonation Models Indicative measurements: e.g. passive samplers Emission inventory Expert knowledge

12. 12 Overview of the Belgian zones