Delhiites wake up to thick haze, low visibility; air quality remains 'very poor'
India | Nov 21, 2020, 09:32 AM ISTAn AQI between 0-50 is marked good, 51-100 is satisfactory, 101- 200 is moderate, 201- 300 is poor, 301-400 is very poor and 401-500 is considered severe.