Question raised in Rajya Sabha on polluted cities in country, 23/07/2015. The ambient air quality is monitored by Central Pollution Control Board and NEERI in Delhi and by Jharkhand Pollution Control Board in Dhanbad under National Air Monitoring programme (NAMP) for three pollutants namely, Sulphur Dioxide (SO2), Nitrogen Dioxide (NO2) and PM10 (particulate matter). As per analysis of data for the year 2011, 2012 and 2013, the levels of SO2 (annual average) in both the cities in Delhi and Dhanbad are within the notified norms of 50 µg/m3 and the levels of NO2 (annual average) in Dhanbad remained within the Norms of 40 µg/m3 while it exceeded in Delhi. The levels of PM10 have exceeded the norms of 60 µg/m3 (annual average) in both the cities. Air quality data of Delhi and Dhanbad during 2011-2013 is enclosed at Annexure-I.