The air quality in Delhi remained in the “severe” category for the fifth consecutive day on Monday due to increased stubble burning and unfavourable wind speed, the Central Pollution Control Board said.
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 9 am, the AQI in Delhi was at 469, indicating “severe” conditions that pose a risk of respiratory problems. Haze shrouded the city again on Monday, reducing visibility significantly.
The AQI in the neighbouring cities of Faridabad, Ghaziabad, Noida, Greater Noida and Gurugram also rose past 460.
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 527 in Delhi at 10.30 am.
The Central Pollution Control Board index is typically lower than that of SAFAR in cases of extreme pollution because it averages values for 24 hours, and caps hourly indices at 500 even if they are of a higher value.
Meanwhile, the PM10 index, which measures the concentration of particulate matter of 10 microns diameter or less in the air, hit 560, 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, climbed to around 377 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 416 on Sunday, 427 on Saturday, 406 on Friday and 450 on Thursday, PTI reported.
The central government’s Air Quality Early Warning System for Delhi said a significant improvement in air quality is not likely because of slow wind speed, particularly during night time, and farm fires.
Air pollution and coronavirus
Delhi’s air quality typically worsens in October and November, but this year the city is tackling problem amid heightened alarm over the health hazard posed by it during the coronavirus crisis. Coronavirus cases have increased in Delhi due to the ongoing festival season with a record 7,745 infections being reported on Sunday, the highest so far.
On Saturday, the Indian Medical Association said the rise in new cases may be linked to air pollution. A day earlier, the health ministry had informed a parliamentary committee that air pollution may lead to faster spread of the coronavirus, as it causes coughing and sneezing.
Last month, the Indian Council of Medical Research had also said, citing international studies, that air pollution levels can lead to rise in coronavirus mortality.
The Delhi government has banned firecrackers in the national Capital and announced steep fines for any violations. Chief Minister Arvind Kejriwal had last week said that no manufacturing industry would be allowed in Delhi in new industrial areas as part of the plan to control air pollution. Only hi-tech and service industries will be permitted to operate in new industrial areas in the city.