Rain worsens pollution, Delhi's air quality in 'very poor' category

Delhi's air quality was recorded in the 'very poor' category after light rains slowed dispersion of pollutants and worsened the pollution situation in the national capital, authorities said Saturday.

According to the Central Pollution Control Board (CPCB) data, the overall air quality index (AQI) of the city was at 332, which falls in the 'very poor' category.

An AQI between 0 and 50 is considered 'good', 51 and 100 'satisfactory', 101 and 200 'moderate', 201 and 300 'poor', 301 and 400 'very poor', and between 401 and 500 'severe'.

The CPCB said 26 areas recorded 'very poor' air quality while six areas recorded poor air quality.

The level of PM2.5 (particles in the air with a diameter of less than 2.5 micrometres) was recorded at 174 and the PM10 level 256, it said.

In the National Capital Region, Ghaziabad, Faridabad, Greater Noida and Noida recorded 'very poor' air quality while Gurgaon, recorded 'poor' air quality, the CPCB data showed.

According to the Centre-run System of Air Quality and Weather Forecasting (SAFAR), the overall air quality over Delhi is 'very poor'.

"This is a typical scenario when a little shower becomes a stumbling block for dispersion of pollutants in spite of not-so-calm surface wind conditions, by introducing huge amount of moisture to make air heavy with drops in temperature, a situation that causes difficulty for dispersion. this process is balancing the air pollution level and keeping it consistently in the lower end of very poor range," the SAFAR said.

"However, by Sunday, wind speed is expected to slow down but at the same time temperature is likely to increase to make foggy conditions better. As a result, air quality will slightly deteriorate by Sunday but will remain in 'very poor' range for next two days and then will start to improve," it said.