Pollutants

Time average

Limit Values (en∙µg∙m−3)

WHO guidelines

NS-05-062 (2003)

NS-05-062 (2019)

SO2

10 minutes

500

-

500

Daily

20

125

50

NO2

1 Hour

200

200

200

Annual

40

40

40

O3

8 Hours

100

120

100

CO

1 Hour

30,000

-

30,000

8 Hours

10,000

30,000 (24 h)

10,000

PM10

Daily

50

260

150

Annual

20

80

40

PM2.5

Daily

25

-

75

Annual

10

-

25

Lead (Pb)

Annual

0.5 - 1.0

2

0.5