Pollution levels in the national capital dropped marginally on Monday morning due to a slight increase in wind speed, but the air quality remained in the 'severe' category.
At 4.38 am, Delhi's air quality index (AQI) was recorded at 438. The AQI at Alipur, Narela and Bawana were registered at 493, 486 and 472 respectively.
On Sunday, the national capital's average AQI stood at 494, the highest since November 6, 2016 when it was 497.
An AQI between 0-50 is considered 'good', 51-100 'satisfactory', 101-200 'moderate', 201-300 'poor', 301-400 'very poor' and 401-500 'severe'. Above 500 falls in the 'severe plus' category.
In the National Capital Region (NCR), Noida (452), Ghaziabad (474) and Greater Noida (454), Gurgaon (396), Faridabad (426) were breathing extremely polluted air.
On Sunday, 21 of the 37 air quality monitoring stations recorded AQI between 490 and 500 with air quality sensors at Aya Nagar, Ashok Vihar, Anand Vihar and Aurobindo Marg peaking out at 7 pm.
The Delhi government had on Friday directed closure of schools till November 5 and banned construction activities after the Supreme Court-mandated Environment Pollution (Prevention and Control) Authority declared a public health emergency as air quality plummeted.
(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)