Air quality zones of historical assessment information

Information on the evolution of air quality in Spain from 2001 to the last official assessment generated in response to Directive 2008/50/EC and RD 102/2011 on improving air quality. A historical evolution of the air quality zones is represented in such a way as to show the situation of each zone in relation to the legislated values for each pollutant; SO2 (hourly and daily limit value), NO2 (annual and hourly limit value), PM10 (daily and annual limit value), Pb, C6H6, CO and PM2.5 (annual limit value), O3, As, Cd, Ni and B(a)P (target value). It should be borne in mind that it is the station with the worst air quality that determines the classification of the area with respect to the legislated values.