New Delhi: The skies over Delhi-NCR took on an ominous grey colour as raging farm fires and stagnant atmospheric conditions pushed the capital's air quality index to the edge of the "severe plus" category, prompting authorities to invoke the final stage of anti-pollution curbs, including a ban on diesel-run light motor vehicles.
The Commission for Air Quality Management -- a statutory body formed in 2021 to tackle air pollution in Delhi-NCR in an order said state governments may take a call on the closure of educational institutions, non-emergency commercial activities and plying of vehicles on odd-even basis.
At 4 pm, Delhi's 24-hour average AQI stood at 450, just a notch short of the "severe plus" category. The concentration of lung-damaging fine particles known as PM2.5 was above 470 micrograms per cubic metre, around eight times the safe limit of 60 micrograms per cubic metre, in many areas.
An AQI of above 400 is considered "severe" and can affect healthy people and seriously impact those with existing illnesses.
The thick layer of pungent smog lingering over the capital lowered visibility to 400 metres and 500 metres at the Safdarjung and Palam airports, respectively, and blotted out the sun partially.
The Centre's air quality panel said BS-VI vehicles and those used for essential and emergency services are exempted from the ban on diesel-run LMVs.
Delhi Environment Minister Gopal Rai has convened a high-level meeting on Friday to discuss the implementation of the curbs under GRAP's stage IV.
The CAQM said central and state governments may decide on permitting work from home.The entry of trucks other than electric and CNG ones in Delhi is banned too. Those carrying essential commodities are exempted.
According to the Energy Policy Institute at the University of Chicago's (EPIC) Air Quality Life Index (AQLI) released in June, the residents of Delhi stand to lose 10 years of life expectancy due to poor air quality.
An analysis conducted by the Delhi Pollution Control Committee (DPCC) in 2021 showed people in the capital breathe the worst air between November 1 and November 15 when stubble burning peaks.
The city records an average PM2.5 concentration of 285 micrograms per cubic metre from November 1 to November 15.
PM 2.5 level from 61 to 120 is considered “moderate to poor”, 121 to 250 is “very poor”, 251 to 350 is “severe” and more than 350 is “severe plus”.
The share of stubble burning in Delhi's PM2.5 pollution jumped to 34 per cent on Thursday, the highest this season so far, which experts said was the reason behind the thick layer of pungent smog over the national capital.
Punjab on Thursday reported 2,666 farm fires. The number stood at 3,634 on Wednesday, the highest this season so far; 1,842 on Tuesday, 2,131 on Monday, 1,761 on Sunday, 1,898 on Saturday and 2,067 on Friday.
Union Environment Minister Bhupender Yadav on Thursday said Delhi Chief Minister Arvind Kejriwal had "officially refused" to use bio-decomposer to prevent stubble burning in Punjab.
Prepared by scientists at the Indian Agricultural Research Institute (IARI) here, the Pusa bio-decomposer is a microbial solution which can turn paddy straw into manure in 15-20 days and prevent stubble burning, a major reason behind a spike in air pollution in Delhi-NCR in October-November.
Kejriwal had Wednesday blamed the central government for rising incidents of stubble burning in Punjab ruled by his Aam Aadmi Party (AAP), saying it had "declined" requests to provide cash incentive to farmers for not burning crop residue.