Air quality in 'very poor' category in Ghaziabad, Noida, Faridabad
The air quality was in the 'very poor' category in Ghaziabad, Noida, Greater Noida and Faridabad while it was in the 'poor' zone in Gurgaon, according to data issued by a government agency on Sunday. Presence of pollutant PM 2.5 and PM 10 also remained high in the five immediate neighbours of Delhi, according to the air quality index (AQI) maintained by the Central Pollution Control Board (CPCB).
According to the index, 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'.
The average 24-hour AQI at 4 pm on Sunday was 318 in Ghaziabad, 332 in Greater Noida, 322 in Noida, 303 in Faridabad and 239 in Gurgaon, according to CPCB's Sameer app.
On Saturday, it was 415 in Ghaziabad, 404 in Greater Noida, 393 in Noida, 348 in Faridabad and 296 in Gurgaon.
The CPCB states that an AQI in the "very poor" category may cause respiratory illness on prolonged exposure and air quality in the "poor" zone may cause breathing discomfort to people.
The AQI for each city is based on the average value of all stations there. Noida, Faridabad, Ghaziabad have four stations each, while Gurgaon has three and Greater Noida two, according to the app.
