Delhi’s air quality has degraded from moderate to poor since September 27, The Times of India reported on Sunday. According to the Central Pollution Control Board’s daily air pollution index, the last days of poor air quality were in June. But air quality this summer and monsoon were better than that of 2016, the pollution board data shows.

Traffic congestion due to Dussehra could have resulted in the deteriorating air quality, experts told the daily. However, the rapid fall in temperature, burning of agricultural residue in neighbouring Haryana and Punjab, and Diwali fireworks are likely to erase the gains of the last three months.

What will the administration do?

From October 15, Delhi will roll out measures under the Graded Response Action Plan to control emissions from all sources. It will be implemented by the Environment Pollution Control Authority between October 15 and March 15.

With the plan in place, measures such as odd-even rules and restrictions on construction work will be automatically implemented when the level of PM2.5 breaches 300 micrograms per cubic metre and PM10 stays above 500 micrograms per cubic metre for two days in a row. These are particulate matters that are 10 or less than 10, and 2.5 or less than 2.5 micrometres in diameter. PM2.5 are the micro particles of dust that cause several lung and respiratory diseases.

Diesel generators will be banned in the city during “very poor” air quality days and parking fees may be hiked by three to four times. The administration will also shut down brick kilns, hot mix plants and stone crushers. The Badarpur thermal power plant will also stop work from October 15.

Keshav Chandra, chairperson of the Delhi Pollution Control Committee, said that they will notify all agencies to monitor waste burning and flouting of construction dust norms and alert the committee of any violations.

Anumita Roy Chowdhury, Executive Director of Centre for Science and Environment said that air pollution control has come under stricter scrutiny after Delhi’s deadly Diwali smog last year. “With sustained action, we can prevent smog incidents this winter and bend the pollution curve eventually,” she was quoted as saying by The Times of India.

Smog in NCR last Diwali

Air quality in Delhi-NCR saw an alarming drop after Diwali celebrations on October 30, 2016. As a result of the smog, schools remained closed for three days from November 7. The National Green Tribunal had also declared an environmental emergency in Delhi, Haryana, Punjab, Rajasthan and Uttar Pradesh.