As per National Ambient Air Quality standards, maximum permissible concentration of NO2 (24 hr. average) in ambient air in residential area is
1
100 μg/m3
2
80 μg/m3
3
60 μg/m3
4
40 μg/m3
As per National Ambient Air Quality standards, maximum permissible concentration of NO2 (24 hr. average) in ambient air in residential area is