The blanket of haze over Delhi thickened on Friday morning with the national capital's pollution levels increasing overnight by around 50 points, taking the overall air quality index (AQI) to 459.
A Central Pollution Control Board official said the AQI entered the 'severe plus' or 'emergency' category late on Thursday night, the first time since January this year. According to official data, the overall Air Quality Index or AQI was 582 at 12:30 am.
If this persists in the 'severe plus' category for more than 48 hours, emergency measures such as odd-even car rationing scheme, banning entry of trucks, construction activities and shutting down schools are taken under the Graded Response Action Plan, the official said.
The hazardous pollution levels forced a number of people to miss morning walks and other activities. The number of masked faces continued to grow as the city remained shrouded in pungent haze for the fourth consecutive day.
At 8:30 am, the capital's overall air quality index stood at 459. It was 410 at 8 pm on Thursday. All the 37 air quality monitoring stations across Delhi recorded the air quality in the severe category on Friday morning.
Bawana was the most-polluted area with an AQI of 497, followed by Delhi Technological University (487), Wazirpur (485), Anand Vihar (484) and Vivek Vihar (482). Neighbouring Ghaziabad was the most-polluted city in the country.