Delhi air quality deteriorates further, slips to 'severe' category

The Air Quality Index (AQI) in the national capital was at 425 --'severe'-- at 8 am, according to SAFAR

Delhi air became severely polluted on Friday, just days after construction, demolition activities resumed in the national capital and educational institutions reopened for physical classes.

The Air Quality Index (AQI) in the national capital was at 425 --'severe'-- at 8 am, according to the Ministry of Earth Sciences' air quality forecast agency SAFAR. Readings below 50 are considered safe, while anything above 300 is considered hazardous or 'severe'.

The deterioration in Delhi's air quality came after it remained in 'very poor' category for three days. The national capital's air quality had improved to 'poor' last week, in view of which all ban were uplifted in Delhi by the Commission for Air Quality Management. 

Delhi's air quality in November was the worst in seven years, data showed. The air became worse after Diwali on November 4 as people violated a ban on bursting firecrackers while the pollution compounded due to an increase in stubble burning by farmers in areas adjoining the national capital.

Delhi this morning was the world's top most polluted city with an AQI of 411, said iQair, a website that tracks air quality worldwide. Kolkata and Mumbai were the only other Indian cities on the list at the sixth and tenth spot with an AQI of 180 and 174 respectively.

Preliminary data from a month-long experiment has shown that indoor air pollution levels were nearly half of the outdoor levels in Delhi-NCR during November-December so far.

Air pollution costs Indian businesses $95 billion or roughly 3 per cent of its GDP every year, according to U.K.-based non-profit Clean Air Fund and the Confederation of Indian Industry, Bloomberg has reported.