5. CONCLUSIONS

This report presents a first evaluation of the reported exceedances of the threshold value for information and warning of the public during summer 1998 (April-August). Information is not necessarily based on validated monitoring data and hence the conclusions drawn should be considered preliminary.

Information on the occurrence of exceedances has been received from all EU Member States for the months April, May, June, July and August. The quality of the exceedance information supplied was good and largely according to EU specifications. Improvements can be made for a number of countries as far as characterization of stations is concerned. Some countries did not supply meta information on stations or supplied information on observed exceedances only on paper. 1066 monitoring stations were assumed to be operational this summer.

The threshold for warning of the public (1h > 360 µg/m³) was exceeded on three days during summer 1998 in the Athens conurbation (2 and 3 July on 2 stations, 29 July on 1 station) and on 1 station on 7 August in France.

The threshold for information of the public (1h > 180 µg/m³) has been exceeded in all Member States with the exception of Ireland, Denmark, Finland and Sweden. The same countries did not report any exceedances last year. In other countries, the number of days on which at least one exceedance was observed ranged from 7 in Belgium to 74 in Spain. 61 % of all stations reported one or more exceedance. On average 3.9 exceedances occurred this year on stations which recorded at least one exceedance with an average duration of 2.7 hours. The average maximum hourly concentration during an exceedance of the threshold this year was 201 µg/m³.

6. References

World Health Organisation (1995): Concern for Europe's tomorrow. Health and the environment in the WHO European region. WHO European Centre for Environment and Health.

Beck, J.P., M. Krzyzanowski, B.Koffi (1998): Tropospheric Ozone in the European Union, The Consolidated Report. To be published by EC/EEA.

De Leeuw, F.,Tim de Paus (1998): Exceedance of EC Ozone Threshold values in Europe. Summary based on the information reported in the framework of the Council Directive 92/72/EEC on air pollution by Ozone. Report to the Commission by the European Environment Agency Topic Centre on Air Quality.

Sluyter, R., E.van Zantvoort (1997): Information document concerning air pollution by ozone. Overview of the situation in the European Union during the 1997 summer season (April-August). Report to the Commission by the European Environment Agency Topic Centre on Air Quality.