The city’s air quality continued to fluctuate on the third day of the anti-pollution measure odd-even, with the level of Ozone showing an upward swing as per Centre’s System of Air Quality and Weather Forecasting and Research (SAFAR) agency.
PM 2.5 and PM 10, fine respirable pollutants, oscillated between poor and moderate levels in areas across the city with them being higher on border areas which have high vehicle density such as Anand Vihar.
At 9 PM, an hour after the curbs on vehicles ended for the day, PM 2.5 and PM 10 were recorded at 234 and 696 micrograms per cubic metre (ug/m3) respectively. The corresponding safe limits are 60 and 100.
As per SAFAR, eight-hour average of Ozone, a gaseous pollutant, which had shown a downward curve since April 15, spiked above 40 parts per billion (ppb), which still falls in the good category. Its eight hour notified average safe limit is 100 micrograms per cubic metre.
According to the air quality index of Central Pollution Control Board, the monitoring station at the East Arjun Nagar had Ozone as the most prominent pollutant while PM 10 dominated areas such as RK Puram, Punjabi Bagh and Anand Vihar.
In its analysis, green body TERI said that over the weekend, the 24-hourly pollutant concentrations “showed a dip” with PM 2.5 concentrations recorded 0.8-2.1 times the prescribed standards at various locations in NCR and PM 10 levels 2.3-3.6 times the standard.
Delhi government’s own analysis of PM 2.5 levels monitored across 74 locations on April 16 found PM 2.5 within “permissible limit” at 42 places and PM 10 levels below 200 at 45 locations.