Polluants

Information threshold

Alert threshold

Sulphur dioxide (SO2)          
350 µg/m3 of sulphur dioxide average measured in an hour          

550 µg/m3 of sulphur dioxide average measured in 3 consecutive hours

Nitrogen dioxide (NO2)          

250 µg/m3 of nitrogen dioxide average measured in an hour

400 µg/m3 of nitrogen dioxide average measured in an hour          

Particulate matter (PM10)

150 µg/m3 of PM10 average measured in 24 hours

200 µg/m3 de PM10 average measured in a 24 hours          

Ozone (O3)

200 g/m3 average ozone   measured in an hour          
260 µg/m3 average   ozone measured in an hour