Noida (UP), Feb 8 (PTI) The air quality was recorded in the 'very poor' category in Ghaziabad, Noida and Greater Noida, while it was 'poor' in Gurgaon and 'moderate' in Faridabad, according to the data issued by a government agency on Monday.
Pollutants PM 2.5 and PM 10 also remained in the air of 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 Monday was 329 in Ghaziabad, 310 in Noida, 319 in Greater Noida, 173 in Faridabad and 298 in Gurgaon, according to CPCB's Sameer app.
On Sunday, it was 251 in Ghaziabad, 238 in Noida, 224 in Greater Noida, 218 in Faridabad and 209 in Gurgaon.
The CPCB states that an AQI in the 'moderate' category may lead to breathing discomfort to people with asthma, lung and heart diseases while 'poor' air quality may cause breathing discomfort to most people on prolonged exposure. Air quality in the 'very poor' zone causes respiratory illness on prolonged exposure.
The AQI for each city is based on the average value of all monitoring stations there. Ghaziabad, Gurgaon and Noida have four such stations while Greater Noida and Faridabad have two stations each, according to the app. PTI KIS TDS TDS