Air quality in the national capital remained in a severe category on Thursday as the Delhi-NCR region continued to be shrouded by a thick layer of toxic smog. Schools in the Delhi-NCR region remained closed as per the direction of the authorities Wednesday night. The closure of the schools was recommended by the Environment Pollution Control Authority (EPCA) citing hazardous air quality.
Several students, who remained confined indoors, chose not to celebrate Children's Day on Thursday. Many students wrote letters to the prime minister urging him to take measures to ensure clean air for them.
"I used to enjoy soccer earlier but now I can only enjoy it on TV. I cannot play outside because the air is too toxic to breathe in," a student, Ishan Mahant, said in the letter.
Another student wrote, "At this point we need a strong directive from the government of India and the governments of the states affected to control this serious condition. We do have belief in our beloved Prime Minister who will surely take strong decision on this."
The air quality index (AQI) deteriorated further to 463 at 2:30 pm in the city, three points more to what was recorded at 9:30 am.
The AQI monitoring centres at Dwarka Sector 8 recorded an AQI of 496, very close to the "severe plus" category. The AQI monitoring centres at JLN Staidum and Nehru Nagar also recorded air quality levels over 490.
The only silver lining was the Aya Nagar air quality monitoring centre which recorded an AQI of 382. The PM 2.5 and PM 10 levels were nearly eight times higher than the normal limits at several locations in the city.
The levels of PM 2.5 - tiny particulate matter less than 2.5 microns in diameter - can enter deep into the lungs and even the bloodstream. The AQI in the satellites cities of Delhi -- Faridabad (441), Ghaziabad (490), Greater Noida (470), Gurgaon (414) and Noida (486) -- was equally bad.
An AQI between 201 and 300 is considered 'poor', 301-400 'very poor' and 401-500 'severe', while the AQI above 500 falls in the severe plus category.
The MeT department has predicted strong winds from Friday, which is expected to slightly bring down the air pollution. On Wednesday, the EPCA had extended the restrictions on dirty-fuel based industries in Delhi-NCR, hot mix plants and stone crushers till the morning of November 15, as the MeT department had said strong winds are expected from Friday, which will bring down the air pollution levels to the very poor category.