A thick haze engulfed the national capital on Tuesday as the air quality remained in the "severe" category and authorities expressed concern that light rainfall in the city may worsen the pollution levels.


The overall air quality index was recorded at 403, which falls in the "severe" category, according to data by the Central Pollution Control Board. An AQI 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".


Seventeen areas in Delhi recorded 'severe' air quality and it was 'very poor' in 14 areas, according to the data. On Tuesday, the level of PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) and PM10 (particles in the air with a diameter of less than 10 micrometres) in Delhi was recorded at 238 and 399 respectively.  -- PTI