Delhi's air quality remained in the 'very poor' category on Monday morning.
At 10.37 am, the air quality index (AQI) was 331. The AQI at Rohini, Bawana and Anand Vihar was 380, 375 and 373 respectively.
Government air quality monitoring service SAFAR said the city's air quality was expected to turn 'severe' by Tuesday. The average AQI stood at 321 on Sunday.
In the National Capital Region (NCR), the AQI in Noida was 358, while Ghaziabad recorded an AQI of 364. Greater Noida, Gurgaon and Faridabad recorded AQI of 346, 304 and 306 respectively.
On Sunday, most of the 37 air quality monitoring stations in Delhi recorded air quality in the 'very poor' category.
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.
With the winter setting in, a dip in the minimum temperature makes the air cold and heavy leading to accumulation of pollutants close to the ground.