After remaining in the top 10 list of cities with unhealthy air quality, the air quality of Bangladesh’s capital Dhaka has finally improved.
Dhaka scored 127 in the US Air Quality Index (AQI) on Thursday. The air was classified as “unhealthy for sensitive groups.”
Even though Dhaka ranked as the most polluted city in the world on Wednesday, it did not make it to the top 10 list of AirVisual
The index was developed by the Environmental Protection Agency for reporting daily air quality of any city or country.
India's capital Delhi and Saudi Arabia's Riyadh occupied the top two spots with individual scores of 337 and 249 respectively, according to data obtained from AirVisual, which shows real-time air pollution index of any city.
Earlier while talking to the Dhaka Tribune, Department of Environment Director (Air quality management) Md Ziaul Haque said: “The air quality in Dhaka will continue to remain like this till the monsoon season starts.”
Bangladesh, one of the most densely-populated countries in the world, has been struggling with air pollution for a long time while Dhaka has continued to rank among the most polluted cities.
Brick kilns, vehicles run by fuels with higher level sulphur, as well as construction works have been identified as major sources of air pollution.
The air quality further declines during the dry months – from October to April – but improves in the monsoon.
The situation is very serious, experts say, pointing out that five of the top 10 causes of deaths in Bangladesh are related to air pollution.
The United States Environmental Protection Agency (EPA) developed the Air Quality Index to report air quality. This AQI is divided into six categories, indicating increasing levels of health concern.
An AQI value over 300 represents hazardous air quality and below 50 the air quality is good.
The index is based on the five criteria pollutants regulated under the Clean Air Act– ground-level ozone, particulate matter, carbon monoxide, sulfur dioxide, and nitrogen dioxide.
The AQI debuted in 1968, when the National Air Pollution Control Administration undertook an initiative to develop an air quality index and to apply the methodology to Metropolitan Statistical Areas.