The air quality in the national capital remained poor for the fifth consecutive day on Sunday with stubble burning accounting for eight per cent of the capital's PM2.5 pollution.

According to air quality forecast agency SAFAR of the Ministry of Earth Sciences, over 1,734 farm fires were observed in the northwest region of Delhi on Saturday.

The Central Pollution Control Board's data showed the capital recorded a 24-hour average air quality index (AQI) of 289. It was 268 on Saturday.


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", and 401 and 500 "severe".

SAFAR said the air quality is likely to improve marginally over the next two days due to change in the wind direction from northwesterly to southeasterly.

The Sub-Committee on Graded Response Action Plan (GRAP) had on Thursday directed authorities in Delhi and NCR states to implement measures under the very poor category in addition to steps listed under poor to moderate AQI category under GRAP.

The Graded Response Action Plan -- a set of anti-pollution measures followed in Delhi and its vicinity towns according to the severity of the situation -- comes into force in mid-October when air pollution levels in the region start worsening.