Tab. I.3 WHO Air Quality Guidelines for the protection of public health (WHO 2000, WHO 2014)


Pollutant
 
Averaging interval Guideline value
PM10 calendar year 20 µg.m-3
24 hours 50 µg.m-3
PM2.5 calendar year 10 µg.m-3
24 hours 25 µg.m-3
Benzo[a]pyrenea)   not recommended
NO2 calendar year 40 µg.m-3
1 hour 200 µg.m-3
O3 8 hours 100 µg.m-3
benzenea)   not recommended
Pb   0.5 µg.m-3
Cdb)   0.005 µg.m-3
Asa)   not recommended
Nia)   not recommended
SO2 24 hours 20 µg.m-3
10 minutes 500 µg.m-3
CO 1 hour 30,000 µg.m-3
8 hours 10,000 µg.m-3
a) These are human carcinogens therefore no safe level of the substance can be established. The WHO guideline value is not recommended. More information on the risks of cancer occurrence see WHO (2000).
b) The recommended value for the prevention of further increase of cadmium in agricultural soils.