The Central Pollution Control Board and the State Pollution
Control Boards are monitoring the ambient air quality across the country under
the National Ambient Air Quality Monitoring Programme. Under this programme,
ambient air quality is being monitored at 424 stations covering 175 cities in
respect of Sulphur Dioxide (SO2), Nitrogen Dioxide (NO2), Suspended Particulate
Matter (SPM) and Particulate Matter of (size less than 10 micro metre (PM10).The air quality data for the year 2009 indicates that the
levels of SO2 have remained the National Ambient Air Quality Standards in all
the cities. However, the levels of NO2 were exceeding the norms in Howrah, Asansol, Kolkata, Delhi,
Jamshedpur, Raipur, Mumbai, Navi Mumbai and Jharia.
During the same period, 91 cities/ towns were found to be exceeding the
standards in respect of PM10. The details may be referred at Annexure-I.