The air quality in Delhi remained in the 'very poor' category on Friday, with the overall figure measuring 314 on the Air Quality Index (AQI), according to the System of Air Quality and Weather Forecasting and Research (SAFAR).
At Lodhi Road, PM2.5 levels were 315, while in Chandni Chowk it was 364. In adjoining areas of Noida it was 328, while in Ghaziabad it was 325, Greater Noida 318 and Faridabad 312. Air quality in Gurgaon was recorded to be in the 'poor' category, with an AQI of 284.
The air quality in the national capital had dipped to 'very poor' on Thursday due to high humidity as a result of light rains. A day earlier on Wednesday, it had improved to 'poor'. Light rain in cold weather is always harmful as it leads to high humidity, creating secondary particulate matter, said Gufran Beig, head of SAFAR.
An AQI between 0-50 is considered 'good', 51-100 'satisfactory', 101-200 'moderate', 201-300 'poor', 301-400 'very poor' and 401-500 'severe'. Above 500 falls in the 'severe-plus emergency' category.
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Meanwhile, the India Meteorological Department (IMD) has said shallow to moderate fog would be noticed in Delhi-NCR until 10 am this morning during which visibility would be around 200-300 metres.
Weather experts have said that Punjab and Haryana received good rains, which is likely to decrease the impact of stubble burning in Delhi's pollution. More than 42,000 farm fires have been recorded in Punjab between September 23 and November 6, much higher than over 30,000 fires recorded last year in this period. In Haryana, over 5,400 fire counts have been recorded as of November 6, a reduction of 472 from last year.
However, pollution from stubble burning in Delhi's air is expected to reach the higher end of the 'very poor' category by Saturday, when the direction of the wind changes, SAFAR had said.