Delhi residents continued to breathe polluted air with the Air Quality Index remaining in the 'severe' category on Saturday.
The Air Quality Index of Delhi continues to remain in the 'severe' category, informed the Centre-run System of Air Quality and Weather Forecasting and Research on Saturday.
As per SAFAR's analysis at 6 am today, Delhi's overall air quality was found to be in the 'severe' category with the overall AQI standing at 533.
Earlier on Friday, the overall air quality of Delhi was plunged into the upper end of the very poor category, SAFAR informed.
What is AQI? How is Delhi's AQI in comparison to previous years?
Air quality index or AQI is the Environmental Protection Agency (EPA's) index for reporting air quality.
An AQI between zero and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor', and 401 and 500 'severe'.
Delhi's AQI reached 462 at noon on Friday. The 24-hour average AQI the day after Diwali was 435 last year, 368 in 2019; 390 in 2018; 403 in 2017 and 445 in 2016. The AQI was 382 on Diwali day this year, 414 in 2020; 337 in 2019; 281 in 2018; 319 in 2017 and 431 in 2016.
What led to the drop from 'very poor' to 'severe' ?
Due to the rampant bursting of crackers on Diwali on Thursday despite restrictions in place, the air quality in Delhi was the poorest in five years post the festival with a rise in incidents of stubble burning in neighbouring states.
The weather office has predicted strong surface winds that will help clear out pollutants in the city's air on Saturday.
Experts said the air quality degraded to severe in Delhi-NCR due to unfavourable weather conditions - calm winds, low temperature and low mixing height - and a poisonous cocktail of emissions from firecrackers, stubble burning and local sources.
The Ministry of Earth Sciences' air quality forecast agency, SAFAR, stated that stubble burning accounted for 36 percent of Delhi's PM2.5 on Friday, the highest in this season so far.
How dangerous are the pollution levels?
Dr Ashok Seth, Chairman, Fortis Escorts Heart Institute on Friday said the pollution levels are dangerous for the elderly people as well as COVID recovered patients.
Speaking to ANI, Dr Seth said, "These are really dangerous levels. AQI (Air Quality Index) levels are especially dangerous for the elderly and those with lung problems and heart disease. Pollution itself leads to chest congestion and bronchospasm. Those with Asthma, bronchitis will start getting worse. It itself predisposes to further chest infections, viral infections and cases of pneumonia. We see a lot of these happening when pollution rises.
"So elderly are at the biggest risk. Also, pollution is to be known for the inflammation of the heart arteries. This results in the precipitation of blood clotting leading to increased heart attacks and worsening of Angina," he added.
Asked about the effect of air pollution to COVID recovered patients, Dr Seth said, "People who recovered from COVID are vulnerable to this (air pollution). Of this group, a lot of them got residue lung problems from minor to major. The toxic gases and particles affect the lungs directly." COVID recovered patients, too, are vulnerable. This is the time for the elderly to stay indoors, be flu-vaccinated and use air purifiers at home continuously."
The air quality in the national capital reached the 'hazardous' category on Friday morning, following the festival of Diwali. The concentrations of Pollution Meter (PM) 2.5 stood at 655.07 in Janpath on Friday morning.
Will the air quality improve?
The air quality in the national capital is likely to improve with higher wind speeds which will flush out pollutants further over the next two days, weather experts said.
(With agency inputs)
