The day-long average of PM 2.5 and PM 10, which are ultrafine particulates, were 178 and 94 micrograms per cubic metre (ug/m3), while the air quality index of the Central Pollution Control Board (CPCB) was poor.
A "poor" AQI essentially means that people will have breathing discomfort on prolonged exposure to such air. On further dip in air quality, AQI will turn "very poor" and "severe".
An official of the CPCB attributed the rise in pollution levels to ground-level activities such as burning of paddy stubble in neighbouring Punjab and Haryana and meteorological conditions including a cyclonic circulation and a fall in wind speed that traps pollutants.
The prescribed standards for PM 2.5 and PM 10 are 60 and 100 micrograms per cubic metre, respectively.
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