NEW DELHI: West Delhi's Rajouri Garden and south Delhi's Lajpat Nagar have logged a high level of pollutants on April 22, the ninth day of the odd-even car-rationing scheme which experts maintain will have a "marginal" impact on the city's overall air quality.
Sumit Sharma, R Suresh and Jai Malik of TERI, who are analysing the impact of ongoing curb on vehicular traffic, explained the daily fluctuations in level of pollutants are observed largely due to meteorological factors like wind speed.
"Wind speeds have been lower during the odd-even week in comparison to the week before. This is one of the reasons why pollutant concentrations were higher during the odd-even week with respect to the week before," they said in a statement.
However, in any case, the contribution of private cars in the overall PM 2.5 (pollutants measuring around 2.5 microns) concentrations in Delhi is not large, hence only marginal PM 2.5 reductions are expected, especially in this season, they added.
According to the Delhi Pollution Control Committee (DPCC), which is monitoring air quality of 74 locations across the national capital daily, Rajouri Garden and Lajpat Nagar had PM 2.5 at 95 and 91 micrograms per cubic metre and PM 10 at 252 and 281 micrograms per cubic metre respectively.
Their corresponding safe limits are 60 and 100 units respectively and prolonged exposure to anything beyond that is harmful.
As per an analysis of SAFAR (System of Air Quality and Weather Forecasting and Research), PM 2.5 rose steadily through the day from around 70 micrograms per cubic metre to 94 micrograms per cubic metre.
SAFAR's eight stations had recorded air quality mostly in the 'poor' category around 7 PM. Although the IGI station had an air quality index of 'very poor'.