Hanoi's air quality at 'very unhealthy' levels

All 35 air quality monitoring stations by the Hanoi Department of Natural Resources and the Environment showed air quality index (AQI) at 100-300 at 9 a.m., meaning air quality was between "poor" and "very unhealthy."

Most of them recorded "unhealthy" levels of air quality, with "very unhealthy" air recorded at four stations at Ly Thai To Street in downtown Hoan Kiem District, Pham Van Dong in Bac Tu Liem District, Cau Dien in Nam Tu Liem District and Tu Hiep in Thanh Tri District. Air quality levels tend to fall as noon approaches.

With AQI levels at "very unhealthy," environmental agencies recommend people to avoid outdoors activities. People should wear masks if they need to go out. People in sensitive groups should stay home and avoid strenuous activities.

Switzerland-based air quality monitoring facility IQAir AirVisual ranked Hanoi as the third most polluted city in the world on Wednesday morning. However, the facility also anticipated that as wind speed increases on Thursday, air pollution in the city is expected to drop considerably.

Air quality monitoring stations by the U.S. Embassy in Hanoi showed an AQI level at 273, categorized as "very unhealthy." Vietnamese environment monitoring app PAM Air meanwhile saw dozens of locations in the city with AQI levels over 300, categorized as "hazardous," when people are recommended to stay home.

PAM Air stations revealed that AQI levels could reach 413 at locations in Dong Anh Town, Dong Anh District, with spots reaching 379 in Thanh Xuan District and 376 in Ba Dinh District.

The latest report by the World Bank and the Hanoi People’s Committee revealed that over 40% of people living in cities are being exposed to PM2.5 levels that are twice the national standards, and much higher than international standards set by the WHO.

Satellite map data revealed that pollution was especially severe during the winter months from October to February next year, due to the impacts of climate change, wind patterns and the burning of straw.

About a third of the PM2.5 dust came from sources in Hanoi, while the rest came from outside areas.

Clear skies and little winds in Hanoi have contributed to increased levels of air pollution, environmental experts said.