A day after Diwali, the air quality in Delhi remained in the “severe” category on Sunday, as bursting of firecrackers worsened the situation, data from the Central Pollution Control Board showed.
According to the agency’s air quality index or AQI, any reading above 100 on a scale of 500 is progressively unsafe for health. At 8 am, the AQI in Delhi was at 467, indicating “severe” conditions that pose a risk of respiratory problems. The AQI further deteriorated, standing at 490 at 5 pm.
While the pollution control board uses 24-hour average data, the Ministry of Earth Sciences’ SAFAR, or System of Air Quality and Weather Forecasting And Research, reports real-time figures. The government-run monitoring agency said the overall AQI struck 545 in Delhi at 9 am.
The situation was no better in the National Capital Region. At 5 pm, both Noida and Gurugram registered an air quality in the “severe” category. The AQI was 448 at Noida’s Sector 62. In Gugugram’s Vikas Sadan, the AQI stood at 403.
A dense layer of smog shrouded the city.
Although the Delhi government had imposed a complete ban on firecrackers, violations were reported across the city and the National Capital Region as crackers could be heard going off till early morning.
In Noida and Greater Noida, where the National Green Tribunal had imposed a blanket ban on firecrackers, five people were arrested for illegal sale of fireworks, PTI reported. Separate first information reports have been lodged over these incidents under provisions of the Explosive Substances Act, the police said.
The PM10 index, which measures the concentration of particulate matter of 10 microns diameter or less in the air, hit 408, SAFAR said. This is coarse particulate matter and mostly dust, which attaches to toxic material from other emissions. A level of 500 is considered “hazardous” and people are usually advised to remain indoors.
Levels of the most dangerous particles, called PM2.5, was 271 micrograms per cubic meter, which is considered hazardous to breathe. Particulate matter smaller than 2.5 microns (or about a ten-thousandth of an inch) is particularly dangerous to human health. Such particles are small enough to travel deep into the respiratory system, potentially impairing lung function. To be considered safe, the National Ambient Air Quality Standards require PM2.5 concentration to be less than 60 micrograms per cubic metre of air in any given 24-hour period.
Delhi’s 24-hour average AQI was 414 on Saturday, 339 on Friday and 314 on Thursday.
SAFAR said an improvement in the air quality is expected starting the second half of Sunday, with light rain expected across the capital. Wind direction is expected to change to south easterly, reducing the impact of farm fires on Delhi’s air. Kuldeep Srivastava, the head of the Indian Meteorological Department’s regional forecasting centre, on Saturday too said that the air quality was likely to improve after Diwali due to an increase in the wind speed.
Delhi’s air pollution typically worsens in October and November due to farmers burning stubble in neighbouring states, unfavourable wind speed and local emission of traffic fumes in the city. Firecrackers ignited for Diwali add to the problem.
Pollution in the city had almost disappeared earlier this year, when the Centre imposed a countrywide lockdown to contain the coronavirus but has returned since the government began lifting restrictions at the end of August.
The emergency situation this year also comes as Delhi is possibly suffering a “third wave” of coronavirus infections. Health experts worry that high air pollution levels over a prolonged period have compromised the disease resistance of people living in Delhi, making them more susceptible to the coronavirus.
The Capital reported 7,340 new coronavirus cases on Saturday in 24 hours, taking the city’s tally to 4,82,170. The toll rose by 96 to 7,519.