Air quality improves but still in very poor category

New Delhi: The air quality in the national capital improved on Saturday but was still in the “very poor” category, two days after Diwali.

The air quality index (AQI) was recorded at 389 as per the CPCB and the levels of ultra fine particles particulate matter (PM) 2.5 and PM 10 were alarmingly high at 206 and 357 microgramme per cubic metre (ug/m3) respectively.

The figures of PM 2.5 and PM 10 were five and three times higher than the prescribed standard of 60 and 100 ug/m3 respectively. The value of AQI improved a bit on Saturday as compared to Friday when the air quality had deteriorated to “severe” level at 403.

According to the CPCB, (Central Pollution Control Board), the volume of pollutants came down on Saturday due to favou-rable meteorological conditions as the wind speed improved and is expected to pick up further and reach up to 9 km/hour, which is adequate for the dispersion of suspended particulates. 

However, among the monitoring stations mai-ntained by the CPCB, eight out of 17 still rec-orded “severe” air quality and the rest were in the “very poor” category, 

A “very poor” AQI comes with the warning that people may develop respiratory illness on prolonged exposure while exposure to “severe” air affects healthy people and seriously impacts those with existing respiratory or cardiovascular diseases.

According to forecast by Safar (System of Air Quality and Weather Forecasting and Research) under the Union ministry of earth sciences, the level of PM 2.5 will remain high and will continue to fall under the “very poor” category even on Sunday and Monday.

PM 2.5 particles are the finest pollutants capable of making inroads into human lung and blood tissues and increase the risk of heart and lung diseases.

As per guidelines by the Central Pollution Control Board (CPCB), AQI level from 0-50 is considered good, 51-100 is satisfactory, 101-200 is moderate, 201-300 is poor, 301-400 is very poor, and 401 and above is severe.

On Friday, the air quality in the national capital had turned “severe”, with Delhiites waking up to smog filled sky. Along with bursting of firecrackers, low temperatures, coupled with calm wind movement and low mixing height post Diwali, also worsened the pollution build up, resulting in pollutants getting trapped in the air for a longer time.

A graded action response plan enforced by the Environment Pollution Control Authority (EPCA), a Supreme Court-monitored committee, and the CPCB, had already come into force from Tuesday, under which actions like shutting down of Badarpur power plant, and ban on diesel generator sets in Delhi are already in place to prevent the air quality to deteriorate further.