Hanoi again topped the list of the world’s most air-polluted cities on February 20, with air quality reaching the purple level.
This morning, Hanoi’s Air Quality Index (AQI) was measured at 227, reaching the purple level or very unhealthy. The concentration of PM2.5 was 10.5 times higher than the annual air quality guidelines set by the World Health Organisation (WHO).
Hanoi is facing with the air pollution (photo by Nguyen Hue)
With this air quality index level, people are advised to avoid outdoor activities, keep windows closed to prevent exposure to polluted air, wear masks when going outside, and use air purifiers indoors.
The AQI is a scale ranging from 0 to 500, with higher values indicating greater pollution levels and health risks. AQI readings above 300 are considered hazardous, while a range of 0-50 signifies good air quality.
According to the National Centre for Hydro-Meteorological Forecasting, the northern region of Vietnam will face another strong cold spell on February 22-24.
Hanoi will continue to experience light rain and mist until this weekend, with the lowest temperature of 15-18 degrees centigrade.