Delhi Struggles to Breathe as Air Turns Poison, '500' AQI Indicates Worst Health Impacts, Says Expert
Vehicles ply amid hazy weather conditions, in New Delhi. (Image: PTI)
For five consecutive days now, the air quality in the national capital continues to be in the ‘severe’ category. On Tuesday morning, stations in Delhi reported an air quality index (AQI) of 500, the highest value on the pollution measurement metric because it cannot be measured beyond it.
While a private air quality monitoring platform even reported an AQI of 999, indicating that the pollution measuring values had maxed out. The whopping numbers are not only indicating the concentration of the hazardous particulate matter both PM 2.5 or PM 10 in Delhi- NCR region but it reveals that these numbers are much higher than indicated by the maximum index value of '500'.
The PM concentrations may be far higher than the criteria for meeting an AQI of 500. But ‘500’ indicates worst air quality with worst health impacts, experts told Hindustan Times (HT).
Delhi: Visibility reduces due to smog in the national capital, as the air quality deteriorates in Delhi-NCR. Visuals from Karkardooma.Air Quality Index (AQI) at 404 ('severe' category) in Anand Vihar, as per Central Pollution Control Board (CPCB). pic.twitter.com/G6CqCiRyQ8— ANI (@ANI) November 11, 2020
While the AQI levels have been oscillating between ends of the ‘severe’ category, since Monday, PM 2.5 and PM 10 concentrations in Delhi have been over 350 micrograms per cubic metres and 550 micrograms per cubic metres, respectively. The daily safe limit of PM 2.5 is 60ug/m3 while that of PM 10 is 100 ug/m3.
“In our estimate, the AQI cannot deteriorate infinitely. Exceeding the 500 scale indicates the situation is terrible. At 500, the maximum damage is done so there is no point going beyond that. It’s a situation similar to the US Environment Protection Agency’s (EPA) hazardous level. It's recommended that people remain indoors but indoor air quality is also impacted,” A Central Pollution Control Board (CPCB) scientist told HT.
As per the United States environment protection body, AQI is a yardstick that states- higher the AQI value- greater the level of air pollution with severe repercussions on citizens’ health.
The kind of air quality you are breathing depends on the concentrations of pollutants such as PM 2.5 or PM 10 and the AQI is basically taking pollution levels from different pollutants and grading them in sub-indices and then calculating an index value based on the pollutant, which is of highest concentration at the time, Anumita Roy Chowdhury, executive director, Centre for Science and Environment (CSE) told HT.
As the AQI continues to deteriorate, System of Air Quality and Weather Forecasting And Research (SAFAR) suggested that residents of the Delhi should avoid all physical activity outdoors, stop any activity level if you experience any unusual coughing, chest discomfort, wheezing, breathing difficulty, or fatigue and consult Doctor.