Delhi’s air quality improved to ‘poor’ today, even as a toxic haze continued to envelop parts of the national capital with the atmosphere being laden with nitrogen dioxide (NO2) and other pollutants. The city’s average Air Quality Index (AQI) was 282 on a scale of 500, classified as ‘poor’, marking a significant improvement from yesterday’s 378, which fell under the ‘very poor’ category.
Since November 23, the air quality in Delhi had remained ‘very poor’, with toxic smog in the city disrupting normal life and even an international cricket match.
The smog in Delhi had cast a shadow on the India-Sri Lanka Test match at the Feroz Shah Kotla Stadium, with captain Dinesh Chandimal and his team wearing N95 anti- pollution masks to combat pollution on Day 2.
The match ended in a draw today with Chandimal admitting that it was tough playing under pollution. Some of the Sri Lankan players had fallen sick.
The concentration of NO2 breached the 24-hour safe limit of 80 micrograms per cubic metre (ug/m3) in areas such as R K Puram (91.03)
and Anand Vihar (86.53) while in Dilshad Garden region it hovered close to 80 unit mark in the evening, according to the Central Control Room for Air Quality Management of the CPCB.
Dipankar Saha, Air Lab Chief of the Central Pollution Control Board (CPCB), said, “Our air quality is improving every hour and we hope it will continue to improve.”
There was depression in coastal areas of the Bay of Bengal in November, while in December there was problem in Arabian sea, the CPCB official said.
“They restricted free air movement from north or northwest to south or southeast. In both the cases, Delhi-NCR experienced very poor wind speed or calm conditions resulting in accumulation of dust at the local level and practically no dispersion of pollutants and we had prolonged very poor AQI,” Saha said.
Now the wind is blowing very easily from north to south with a speed of 4.5 m/s, which has resulted in dispersion of pollutants, leading to “improvement in the air quality after a long pause,” he added.
The United Nations marked yesterday as the first International Smog Day. It is a moment to remember all of the people who have died prematurely, and avoidably, because of the air pollution, the United Nations Environment Programme (UNEP) had said in a statement.
Pollution is considered severe plus or emergency when readings of PM2.5 and PM10 cross 300 and 500 ug/m3, respectively. The corresponding prescribed standards are 60 and 100.
An AQI between 0-50 is considered Good, 51-100 Satisfactory, 101-200 Moderate, 201-300 Poor, 301-400 Very Poor, and 401-500 Severe.