New Delhi: Flight operations at the Chennai airport had taken a major hit in the early hours of Saturday. At least 12 Chennai-bound flights were diverted and around 10 departures were delayed due to low visibility in the city. Air quality index or AQI at several places in the city were classified as "hazardous", as people across the city celebrated Bhogi, marking a significant spike in air pollution. Bhogi is the first day of the four-day Pongal festival, celebrated by burning discarded household items. Due to the resulting smog, visibility dropped down to 50 metres. On Saturday morning, the AQI in the Manali area of Chennai is worse than in parts of Delhi, with the level of the lethal particulate matter 2.5 -- a key indicator of air pollution -- at 599. In the Alandur area of Chennai, the PM 2.5 reading was 303. The permissible level of PM 2.5 is 60 as per national standards.
 

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