Delhi's air quality remained in the "severe" category today owing to unfavorable weather conditions and a significant increase in contribution from stubble burning, authorities said.
The overall Air Quality Index (AQI) was recorded at 423, according to data from the Central Pollution Control Board (CPCB).
The AQI was recorded "very poor" yesterday morning, but it again slipped to the severe level in the evening.
28 areas recorded 'severe' AQI, 7 areas 'very poor' quality
Today, the PM2.5 (particles in the air with a diameter of less than 2.5 micrometers) level was recorded at 299, while the PM10 (with a diameter of less than 10 micrometers) level was recorded at 477, according to data from the CPCB.
28 areas in Delhi recorded air quality in the "severe" category, while 7 areas recorded "very poor" air quality.
Here's what is defined as 'severe' AQI
An Air Quality Index between 0 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".
Stubble burning in neighboring states recorded 'the largest-ever' on Thursday
According to the Indian Institute of Tropical Meteorology (IITM), the increase in PM2.5 concentration is due to stable meteorological conditions trapping of the pollutants in Delhi (very less dispersion) and significant increase in contribution from stubble burning.
Stubble burning in neighboring states on Thursday was the "largest-ever recorded" this year.
The IITM said it could lead to a further deterioration of Delhi's air quality.
Devastating air quality
Post Diwali, Delhi recorded an AQI of 642
Delhi's air quality has remained in the "severe" category for the past two days with the highest pollution level of the year recorded a day after Diwali on Thursday at an AQI of 642.
The Environment Pollution Control Authority has asked the departments concerned to extend the ban on construction activities, industries using coal and biomass and entry of trucks till November 12.