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The national capital and its adjoining suburbs were blanketed in a grey haze on Wednesday morning, dipping visibility to 300 meters at some places, causing train delays and slowing down flight operations here. Some 30 trains coming to Delhi and 30 flights landing or taking off from the Delhi airport were delayed, according to officials.
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The air quality in Delhi and adjoining Noida (Uttar Pradesh) and Gurgaon (Haryana) continued to be alarmingly bad on Wednesday. Due to worsening air pollution, authorities closed schools on Wednesday and Thursday.
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The situation prompted Delhi Chief Minister Arvind Kejriwal to write on Twitter: "Delhi has become a gas chamber. Every year this happens during this part of the year. We have to find a solution to crop burning in adjoining states."
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The average air quality index was 477 and the level of dangerous PM2.5 particles was "severe" at 475 microgrammes per cubic metre -- about 19 times more than permissible globally.
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The permissible range for PM2.5 is 60 as per Indian standards and 25 globally.