Delhi's air quality remained 'very poor' on Sunday though a change in meteorological conditions due to a western disturbance may bring some relief, according to monitoring agencies.
The capital's air quality index (AQI) stood at 385 at 9 am.
The 24-hour average AQI, recorded at 4 pm every day, was 389 on Saturday, 415 on Friday, 390 on Thursday, 394 on Wednesday, 365 on Tuesday, 348 on Monday and 301 on Sunday (November 19).
An AQI between zero and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor' , 301 and 400 'very poor', 401 and 450 'severe' and above 450 'severe-plus'.
The national capital has recorded 10 severe air quality days this November so far.
The city recorded just three severe air quality days in November last year, while it experienced 12 such days in 2021, the maximum in the month since the Central Pollution Control Board (CPCB) began monitoring.
There were nine such days in November 2020; 7 in 2019; 5 in 2018; 7 in 2017; 10 in 2016, and 6 in 2015, according to CPCB.
The recent rise in the AQI levels comes in the wake of the Centre last Saturday removing several curbs, including a ban on construction work and the entry of polluting trucks in Delhi, which saw a drop in pollution levels, contributed to by a favourable wind speed and direction.
According to a joint project by the Delhi government and the Indian Institute of Technology-Kanpur, biomass burning stood out as the top reason for Delhi's foul air, contributing 31 to 51 per cent to the capital's air pollution in the last few days.
The data revealed that vehicular emissions accounted for about 31 to 40 per cent of the capital's air pollution the previous day.
Delhi Environment Minister Gopal Rai has directed agencies and departments concerned to ensure strict implementation of curbs on polluting vehicles and check the increasing incidents of biomass burning.
