Delhi’s air quality on Tuesday deteriorated to the “very poor” category for the first time this season. Government-run monitoring agency System of Air Quality and Weather Forecasting and Research, or SAFAR, said the air quality index was not likely to improve for the next two days.
Air pollution typically worsens during the winter months from October to December. It was in the “poor category” for six consecutive days after it began to decline on October 7 for the first time in over three months.
The overall air quality index or AQI was 307 at 2.30 pm in Delhi. An index reading between 0 and 50 puts the air quality in “good” category. A reading between 51 and 100 puts it in the “satisfactory” category, between 101 and 200 in the “moderate” category, and between 201 and 300 in the “poor category”. The air quality is said to be “very poor” when the index value falls between 300 and 400. An index value between 400 and 500 puts the quality in the “severe” category.
The 24-hour average AQI was 261 on Monday, the worst since February, according to PTI. It was 216 on Sunday and 221 on Saturday.
On Tuesday morning, the maximum wind speed was 4 kilometers per hour, according to the India Meteorological Department. Low temperatures and stagnant winds help in accumulation of pollutants near the ground, affecting air quality.
Last year, New Delhi suffered nine consecutive days in late October and early November when the air quality was hazardous. Authorities had declared a public health emergency and closed schools and all construction activity as pollution in the city hit its worst level.