It is expected that in the next two or three days, downpours will come to the capital city and the air quality may be improved.

A bird’s eye view shows smog covering Hanoi on September 30 morning.
Photo: Nam Tran 

The air pollution index in the capital city of Hanoi has soared to hazardous levels over the past two days, and downpour is expected to end air pollution wave in the city, local media reported.

AirVisual, an international air quality monitoring application from IQAir which generates data from public, on-site and real-time monitoring stations, recorded on September 30 that Hanoi remained the most polluted city in the world with the Air Quality Index (AQI) exceeding the red-warning level. 

At 8:00 am on September 30, a bird’s eye view shows Hanoi blanketed by smog. AirVisual recorded Hanoi’s AQI at 385 at 4:00 am, the highest level the city has witnessed this month. 

 Many places in Hanoi in recent days even reach purple-warning level for air pollution. Thus, children, the elderly and individuals with respiratory and heart diseases are recommended to avoid sustained and high-intensity outdoor exercises when AQI levels reach 150 or above.

 Hanoi authorities have pointed to the large number of vehicles in the city’s downtown as one of the main causes of air pollution. 

 Urbanization with many works in execution, seasonal weather transition and post harvest straw burning in Hanoi’s suburban districts are also blamed for the low quality of Hanoi’s air, said officials of the Hanoi Department of Natural Resources and Environment.

 AirVisual measures Hanoi’s air quality based on 10 monitoring stations run by Hanoi authorities and four by non-profit organizations. However, this result is vastly different compared to the AQI recorded by the automatic monitoring systems in Hanoi.

 Besides, each country has different ways of assessing air quality. Thus, these are sources of reference and people should not be panic, the officials noted.

 They said it is expected that in the next two or three days, downpours will come to the capital city and the air quality may be improved.

 However, many residents have voiced their concern, urging the city to take action, instead of offering excuses for worsening air pollution.