India, Oct. 18 -- The city's air quality deteriorated on Saturday, recording a 24-hour average Air Quality Index (AQI) of 122, compared to 99 on Friday, as low wind speeds and temperature inversion continued to trap pollutants close to the surface, with more than half the locations of the 23 active monitoring stations across the city experiencing unhealthy air. The primary pollutant was PM10 (particulate matter of size less than 10/ugm3).

As many as 15 stations recorded 'moderate' air quality while the remaining fell in the satisfactory category. According to the Central Pollution Control Board, an AQI between 1-50 is classified as good, 51-100 is satisfactory, 101-200 is moderate, 201-300 is 201-300 is poor, 301-400 is very poor and 401...