Delhi air quality dips to very poor category

New Delhi: Amid the chilly weather, the air quality in the national capital dipped to very poor quality as the overall Air Quality Index (AQI) of the city reached 311 on Thursday morning, according to data from the System of Air Quality and Weather Forecasting And Research (SAFAR).

The AQI at Dhirpur entered into a severe category with PM 2.5 at 324, under a 'very poor' category.

Experts said that the air quality may also remain in a very poor category on Friday.

The 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.

In Pusa, the AQI recorded PM 2.5 at 318 very poor category.

At Lodhi Road, the Air Quality Index with PM 2.5 concentration was at 3o1 under the very poor category and the PM 10 stood at 163 under the moderate category. In Ayanagar the PM 2.5 was at 286, poor category while the PM 10 reached 156, in moderate category.

The Air Quality Index at the city's Mathura Road was also under the very poor category with PM 2.5 at 312 with PM 10 concentration at 255 under the poor category.

According to the forecast from the System of Air Quality and Weather Forecasting And Research (SAFAR), the air quality of the city will deteriorate further under a very poor category with PM 2.5 reaching 322 and the PM 10 concentration at 184 under 'moderate category' on Friday.

However, the Air Quality Index of Delhi's neighbouring cities of Noida stood at 339 under very poor category and the PM 10 concentration at 207 under poor category, while Gurugram's AQI was reported at 303 under the very poor category and the PM 10 concentration at 146 under moderate category.

Meanwhile, Delhiites woke up to a thin layer of fog and a cold day with Palam weather station in Delhi recording a minimum temperature of 9.7 degree Celsius while Safdarjung recorded a minimum temperature of 7 degree Celsius.

A 'cold day' is when the minimum temperature is less than or equal to 10 degrees Celsius below normal and the maximum temperature is at least 4.5 degrees below normal. A 'severe cold day' is when the maximum is 6.5 degrees or more below normal. A 'severe' cold wave is when the minimum temperature dips to two degrees Celsius or the departure from normal is more than 6.4 degrees Celsius.