Pollution levels shoot up 15 times in residential areas; industrial areas register a dip

New Delhi

New Delhi

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The spike in pollution levels on Diwali night was much higher in Delhi’s residential neighbourhoods in comparison to industrial areas. A few residential colonies such as Aya Nagar, Ashok Vihar and Dilshad Garden registered pollution levels that were at least 14-15 times higher than the permissible limit.

This, experts say, was primarily because of the cracker-effect and other Diwali-related activities such as the movement of cars, which were concentrated in residential areas on Sunday night.

Government data shows that in places such as Ashok Vihar, Rohini and Ayanagar, the hourly concentration of PM2.5 had crossed the 900ug/m3 mark by 11 pm on Diwali night. This was at least 15 times above the daily permissible limit of 60ug/m3.

Data available with the Central Pollution Control Board (CPCB) showed in some residential areas such as Ayanagar and RK Puram, PM2.5 levels – the ultrafine particles that can reach up to your lungs – shot up by almost three times to five times on Diwali over the previous day. In most of the other residential areas, the spike was almost twice over the previous day.

Compared to this, the industrial areas registered a much milder spike in PM2.5 levels. In some areas such as Bawana, there was apparently no spike in the concentration of ultrafine particles, while in places such as Mundka, it shot up by around 13 digits.

“Even though bursting of conventional fireworks was prohibited and only green fireworks were allowed, the ban was violated. This resulted in heavy pollution in residential areas. But compared to last year, this year, the bursting of fire crackers was lower,” said BS Vohra, who heads the East Delhi RWA Joint Front.

This was in tune with the forecast issued by Safar, the union ministry’s pollution forecasting wing, on Saturday. The agency had said residential neighbourhoods such as Okhla, Dwarka, Delhi University and Lodhi Road among others, were identified as ‘hot spots’. But industrial areas that otherwise remain polluted round the year, such as Narela and Bawana, among others, would remain less polluted.

Industrial areas actually saw a dip in pollution, particularly in the PM10 levels, because of lack of vehicular movement, which usually triggers road dust.

The average concentration of PM10 dropped from 394ug/m3 to 350ug/m3 at Bawana. In Narela and Mundka, the levels of PM10 dropped from 336ug/m3 and 401ug/m3 to 318ug/m3 and 347ug/m3.

“PM10 comes mainly from road dust and construction activities. The moment you stop industrial activities and vehicular movement, the level of PM10 drops. This is what happened in the industrial areas of Delhi on Diwali day,” said D Saha, former head of the CPCB’s air quality laboratory.