21. 11. 96 Official Journal of the European Communities No L 296/55 COUNCIL DIRECTIVE 96/62/EC of 27 September 1996 on ambient air quality assessment and management THE COUNCIL OF THE EUROPEAN UNION, Having regard to the Treaty establishing the European Community, and in particular Article 130s (1) thereof, Having regard to the proposal from the Commission ('), Having regard to the opinion of the Economic and Social Committee (%), Acting in accordance with the procedure laid down in Article 189c of the Treaty (%), Whereas the fifth action programme of 1992 on the en- vironment, the general approach of which was endorsed by the Council and the Representatives of the Govern- ments of the Member States, meeting within the Council, in their resolution 93/C 138/01 of 1 February 1993 (¥, en- visages amendments to existing legislation on air pollu- tants; whereas the said programme recommends the esta- blishment of long-term air quality objectives; Whereas, in order to protect the environment as a whole and human health, concentrations of harmful air pollu- tants should be avoided, prevented or reduced and limit values and/or alert thresholds set for ambient air pollution levels; Whereas, in order to take into account the specific forma- tion mechanisms of ozone, these limit values and alert thresholds may need to be complemented or replaced by target values; Whereas the numerical values for limit values, alert thresholds and, as regards ozone, target values and/or limit values and alert thresholds are to be based on the findings of work carried out by international scientific groups active in the field; Whereas the Commission is to carry out studies to analyse the effects of the combined action of various pollutants or sources of pollution and the effect of climate (" OJ No C 216, 6. 8. 1994, p. 4. ) O] No C 110, 2. 5. 1995, p. 5. (*) Opinion of the European Parliament of 16 June 1995 (O] No C 166, 3. 7. 1995, p. 173), Council common position of 30 November 1995 (O] No C 59, 28. 2. 1996, p. 24) and decision of the European Parliament of 22 May 1996 (O] No C 166, 10. 6. 1996, p. 63). () OJ No C 138, 17. 5. 1993, p. 1. on the activity of the various pollutants examined in the context of this Directive; Whereas the ambient air quality needs to be assessed against limit values and/or alert thresholds, and, as regards ozone, target values and/or limit values taking into account the size of populations and ecosystems exposed to air pollution, as well as the environment; Whereas, in order for assessment of ambient air quality based on measurements made in Member States to be comparable, the location and number of sampling points and reference methods of measurement used should be specified when values are set for alert thresholds, limit values and target values; Whereas, to allow for the use of other techniques of es- timation of ambient air quality besides direct measure- ment, it is necessary to define the criteria for use and required accuracy of these techniques; Whereas the general measures set up under this Directive have to be supplemented by others specific to individual substances covered; Whereas these specific measures need to be adopted as soon as possible in order to fulfil the overall objectives of this Directive; Whereas preliminary representative data on the levels of pollutants should be collected; Whereas, in order to protect the environment as a whole and human health, it is necessary that Member States take action when limit values are exceeded in order to comply with these values within the time fixed; Whereas the measures taken by Member States must take into account the requirements set by regulations con- cerning the operation of industrial installations in con- formity with Community legislation in the field of in- tegrated prevention and reduction of pollution when this legislation applies; Whereas, because these actions require time to be imple- mented and become effective, temporary margins of tolerance of the limit value may need to be set;