Pollutants

Nigeria (FMEV)

National Air Quality Standard for Nigeria

WHO Guidelines and World Bank Standards

Long-Term Tolerance Limits 24 Hours (mg/m3)

Short-Term Tolerance Limits 30 min (mg/m3)

Suspended particulate matter

0.015

0.5

250 mg/m3 (24 h)

600 mg/m3 (1 h)

60 - 90 mg/m3 (annual mean)

150 - 230 mg/m3 (24 h)

Carbon dioxide

10 vol. %

-

-

Carbon monoxide

1.0

0.5

10 mg/m3 (1 h)

20 mg/m3 (8 h)

60 mg/m3 (24 h), 10 mg/m3 (8 h),

30 mg/m3 (1 h)

Nitrogen dioxide

0.085

0.085

75 - 113 mg/m3 (24 h)

40 - 50 mg/m3 (annual), 150 (8 h),

200 mg/m3 (24 h)

Sulphur dioxide

0.05

0.5

0.01 (24 h)

0.1 (1 h)

50 mg/m3 annual, 350 mg/m3 (1 h),

125 mg/m3 (24 h)

Benzene

0.8

0.2

-

1 mg/ m3

Toluene

0.6

0.6

-

1 mg/m3 (odour) 7.5mg/m3

Ethylene

5.0

5.0

-

-

Xylene

-

0.2

-

-

Hydrocarbon (total)

2.0

5.0

160 mg/m3 (3 h)

160 mg/m3

Cadmium

0.003

0.01

-

10 - 10 mg/m3, 0.04 mg/m3

Chromium

0.001

0.0015

-

1 mg/ m3

Lead

0.005

0.002

-

0.5 - 1 mg/m3 (annual)

Manganese

0.01

0.03

-

1 mg/m3 (annual)

Vanadium

0.002

-

-

1 mg/m3 (24 h)