The air quality in Delhi improved to the 'poor' category on Monday, according to the Central Pollution Control Board (CPCB). The national capital recorded an overall AQI of 281, in the "poor" category, against Sunday's "very poor" AQI of 318. However, the air quality in some areas like Anand Vihar, Wazirpur and Shadipur are still in the 'very poor' category.