The air pollution level in the Indian capital region Delhi on Thursday became severe, officials said.
According to the Central Pollution Control Board (CPCB), the overall air quality index (AQI) remained in the severe category at 442.
The air quality was severe and prominent pollutants were PM 2.5 and PM 10, said the CPCB.
The information has been received from monitoring stations set up across Delhi.
Experts said PM 2.5 were fine particles that were 2.5 microns or less in diameter and can travel deep into the respiratory tract, reaching the lungs and entering the bloodstream.
Health officials have advised people, especially those with respiratory illness, in Delhi to minimise outdoor exposure until the improvement in air quality.
Doctors said severe air quality affects healthy people and seriously impacts those with existing pulmonary diseases.
As per the CPCB, AQI between 0-50 is considered good, between 51 and 100 satisfactory between 101 and 200 moderate, and between 201-300 poor.
Also between 301 and 400 was very poor, and between 401 and 500 was severe and beyond 500 was severe plus emergency.
Air pollution continues to worsen in Delhi and it gets aggravated during winter months.
The deterioration in air quality is attributed to slow wind speed and stubble burning (farm fires) in the neighbouring states.
Indian capital city Delhi is among the topmost polluted cities in the world with industrial activities and vehicular traffic being significant contributors to air pollution in the city, along with rampant construction.
Reports said several residents have reported breathing difficulties, with the elderly and schoolchildren being the worst hit.
A leading private school has suspended physical classes for students at its branches in Delhi and Haryana in view of the deteriorating air
quality.
It would be conducting online classes from Friday, a local television news channel NDTV said in its report.
“This came a day after the National Commission for Protection of Child Rights urged Delhi Chief Minister Arvind Kejriwal to shut schools till air quality improves,” NDTV said.
Xinhua
