A thick blanket of smog has enveloped Delhi and the National Capital Region early on Wednesday, bringing down visibility considerably as air quality dipped to "very poor" levels.
Central Pollution Control Board (CPCB) data indicated that average air quality index in Delhi touched 349 at 6 a.m. NCR cities too were abysmal with AQI recorded in Faridabad at 196, at 266 in Gurugram, 276 in Ghaziabad, at 289 in Greater Noida, and at 269 in Noida.
The readings on Aya Nagar in the national capital were at its highest, reaching 406 and crossed the "severe" mark. Several other areas in the capital registered AQI values between 300 and 400.
According to the Switzerland-based air quality monitoring organization, IQAir, Delhi's AQI had even reached as high as 1,133 in certain locations earlier, thus categorizing pollution as hazardous, with PM2.5 identified as the main pollutant.
The thick smog accompanied by moderate fog and mist combined to create a problem of low visibility during the early morning hours. Experts say that the hazy conditions could continue throughout the evening, thus raising health risks, particularly to respiratory disease patients.
The AQI, or Air Quality Index, in Delhi has been "very poor" since October 30, when it was first recorded at 307. The situation is largely seasonal; the worst pollution happens in autumn - October and November, when farmers in the agricultural states of Punjab and Haryana clear fields by burning stubble.
Air quality in several parts of Punjab and Haryana also remained worrying, with most places falling in the "poor" category, while Chandigarh, the joint capital, recorded a "very poor" AQI of 349 till Tuesday night. In Punjab, 83 fresh farm fires were reported and had taken the season's tally to 7,112 so far.
The CPCB classifies AQI as follows: 0-50 is "good, satisfactory"; 51-100 is "satisfactory, moderate"; 101-200 "poor"; 201-300 is poor; 301-400 is very poor; 401-450 is severe; and greater than 450 is severe plus.
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