In Hanoi, parents send air purifiers to school as pollution triggers health warnings

Municipal monitoring stations and sensors in several northern localities reported poor and very poor air-quality readings over the past 10 days, prompting schools to advise mask use and allow online study for students with respiratory risks.

Some parents lent air purifiers to classrooms at Thanh Xuan Trung Middle School, its principal said, adding that teachers were instructed to keep rooms sealed and run ventilation systems throughout the day.

Hanoi's Department of Environment said the city has issued urgent instructions to update public warnings more frequently and deploy satellite and drone monitoring to detect industrial sources of pollution. 

Authorities said inspections found some factories on the capital's outskirts continued emitting black smoke despite the alerts.

Hospitals have reported a rise in respiratory cases. 

National Lung Hospital said outpatient visits for asthma, bronchitis and pneumonia had increased by 20 percent to 30 percent, while Friendship Hospital reported respiratory admissions doubling or tripling in the past two weeks.

The Ministry of Agriculture and Environment said the prime minister has approved a 2026–30 national action plan on air-quality management, which includes a phased tightening of vehicle emissions standards for cars and separate rules for motorbikes. 

Hanoi and Ho Chi Minh City will be subject to stricter limits under the draft regulations.

Ho Chi Minh City, which has a population of about 14 million after recent administrative mergers with old Binh Duong and Ba Ria–Vung Tau Provinces, faces similar pollution pressures. 

Studies cited by municipal authorities show the city has more than one million cars and 7.3 million motorbikes, which account for most emissions of nitrogen oxides, carbon monoxide and particulates.

The southern city is rolling out measures under national directives, including plans to convert its bus fleet to electric or green energy by 2030 and propose low-emission zones in central and coastal areas.