Delhi's air quality remained 'very poor' on Monday as weak winds trapped pollutants, recording an overall Air Quality Index (AQI) of 324 at 6:05 am, according to data from the Sameer app developed by the Central Pollution Control Board (CPCB).
On Sunday as well, the national capital's AQI remained in the 'very poor' category, recording an overall AQI of 366. Three monitoring stations also recorded "severe" air quality above 400, as per data from the CPCB.
Many of the neighbouring cities in the National Capital Region (NCR) also recorded 'very poor' air quality, including Noida (311), Ghaziabad (334) and Gurugram (304).
An AQI between 0 and 50 is considered "good", 51-100 "satisfactory", 101-200 "moderate", 201-300 "poor", 301-400 "very poor" and 401-500 "severe", according to the CPCB standards.
On Sunday, at least five individual active ambient air quality stations at a particular time recorded AQIs in the 'severe' category.
This can lead to breathing issues for many, especially people with lung or heart diseases, children and the elderly.
The AQEWS also said that the air quality in the national capital is expected to remain in the "very poor" category till November 4.
On Sunday evening, the PM2.5 level was recorded at 189.6 micrograms per cubic metre, while PM10 stood at 316, according to the CPCB data. Notably, PM2.5 refers to fine particles that are 2.5 micrometres or smaller in size, while PM10 includes larger particles up to 10 micrometres in diameter.
Mahesh Palawat, vice president at Skymet meteorology said atmospheric conditions were unfavourable for dispersion of pollutants, leading to gradual accumulation, according to the earlier HT report. "Winds picked up - touching around 10 km/hr during the day on Sunday, which led to an improvement in the AQI. Otherwise, we were mostly seeing calm winds," he was quoted as saying
He said that the wind direction was variable through the day, barring the afternoon period, when it switches to westerly and northwesterly, favourable for transport of stubble smoke to Delhi.