On October 30 and 31, 2016, from 9PM to the next morning, North India–especially parts of Delhi, Uttar Pradesh and Bihar–recorded PM 2.5 levels.
●    PM 2.5 is fine particulate matter about 30 times finer than a human hair. 
●    These particles can be inhaled deep into the lungs, causing heart attacks, strokes, lung cancer and respiratory diseases, and are known to pose the greatest risk to human health. 
●    Their measurement is considered to be the best indicator of the level of health risks from air pollution, according to the World Health Organization.
●    South Delhi’s 24-hour average PM 2.5 levels in 2016 were 38% higher than on Diwali night 2015.
●    The next day, these levels were twice as high as the day after Diwali in 2015, crossing 26 times levels considered safe. 
●    On the morning of November 1, 2016, citizens in Delhi woke up to an average PM 2.5 level of over 700 µg/m&³3;–some of the highest levels recorded the world over.
●    It’s 29 times above WHO standards.

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