Hanoi chokes as air quality reaches crisis level

Residents of Hanoi are facing hazardous air pollution as Air Quality Index, or AQI, levels entered the purple zone, a threshold considered very unhealthy, with data on Wednesday ranking the capital the third most polluted city in the world.

According to real-time measurements from the IQAir app on Dec 10, Hanoi recorded an AQI of 223, placing it third worldwide for air pollution.

Data from the Ministry of Agriculture and Environment's monitoring system also showed dangerously high AQI levels, with many locations reaching the purple threshold.

Experts warn that when AQI reaches hazardous levels between 301 and 500, the public should minimize outdoor exposure, avoid all outdoor activities and remain indoors as much as possible. Recommendations for sensitive groups are even stricter, as they should not go outside at all and must ensure indoor spaces have safe, well-ventilated air.

Hanoi has spent several days shrouded in thick smog laced with fine particulate matter, driving the air quality index from unhealthy red levels to very unhealthy purple.

Le Thanh Thuy, Deputy Head of the Environmental Management Division under the Hanoi Department of Agriculture and Environment, noted that the capital is under "tremendous pressure" from air pollution, with PM2.5 concentrations remaining high and fluctuating sharply.

According to the department, air quality varies significantly across areas, with central districts showing higher AQI levels, partly due to higher traffic, dense construction activity, and congestion.

Thuy explained that year-end urban upgrading projects, frequent traffic jams, increased transportation of construction materials, and open burning of waste and agricultural by-products all worsen air pollution.

"The weather conditions have not been favorable while many activities peak at the end of the year, placing enormous pressure on Hanoi," she said.

Hoang Duong Tung, Chairman of the Vietnam Clean Air Network, stressed that Hanoi's air pollution problem does not originate solely within the city but also from neighboring provinces such as Bac Ninh, Ninh Binh and Hung Yen.

To address this, he said, authorities must apply AI to validate, clean and synchronize air quality and pollution source data.

"Only with accurate, transparent, real-time data can we build appropriate scenarios and policies," he said.

Also on Wednesday, the National Assembly approved a Resolution on the implementation of environmental protection policies and laws since the 2020 Law on Environmental Protection took effect.

The Resolution calls for urgent action to improve air quality in the country's two largest cities, Hanoi and Ho Chi Minh City, in 2025-26, while setting out a roadmap for emission reduction and stronger environmental monitoring in subsequent years.

By 2030, the Resolution sets a target to reduce the average annual PM2.5 concentration in Hanoi by approximately 20 percent relative to the 2024 baseline at all monitoring stations in the national network.

To reach these goals, lawmakers require strict vehicle emissions controls, limits on highly polluting vehicles in major urban centers, and the removal of vehicles that fail to meet minimum technical standards.

The Resolution also mandates tighter regulation of waste generated from construction and transport activities; curbs on the burning of agricultural by-products; and expanded collection and treatment of domestic wastewater to prevent further pollution in densely populated areas.

In addition, the National Assembly directs the swift completion and operation of a national environmental information and data system, including an integrated public map of environmental quality. This system will be implemented in major cities such as Hanoi and Ho Chi Minh City, connected to national databases, and will provide real-time information to support management, monitoring, and early-warning efforts.

VIET NAM NEWS