U.S. weather forecast service AccuWeather recorded the air quality index (AQI) in Hanoi on Monday at 61, ranking it "poor."
The service recorded a PM2.5 level of 30 µg/m3 in Hanoi on Monday. Hanoi's AQI is forecast to be between 63 and 80 until Thursday. A higher index means worse air pollution.
In HCMC the air quality on Monday was ranked as "fair" by AccuWeather, with the AQI at 20. The level of PM2.5 in the air was recorded at 20 µg/m3, also classified as "fair."
The air quality in HCMC is projected to remain "fair" through Thursday, with the AQI forecast to be between 20-28.
Switzerland-based air quality monitoring facility IQAir AirVisual ranked Hanoi’s AQI on Monday at 155, meaning the air quality is "unhealthy." The PM2.5 level was recorded at 62.6 µg/m3, which is 12.5 times that of WHO air quality standards, according to AirVisual.
The AQI in Hanoi will range from 115 to 154 until Sunday, which is either unhealthy for sensitive groups, or simply unhealthy.
AirVisual recorded the AQI in HCMC on Monday at 57, which means a moderate air quality, and PM2.5 level of 15 µg/m3.
Until next Thursday, the air quality in HCMC is expected to stay at a moderate level, with the AQI ranging from 61 to 123, it said.
PM2.5 is defined as ambient airborne particulate that measures up to 2.5 microns in size, just a fraction of the width of a human hair. Their microscopic size allows these particles to be absorbed deep into the bloodstream upon inhalation, potentially causing health issues such as asthma, lung cancer, and heart disease.
Exposure to PM2.5 has been linked to negative health effects such as cardiovascular disease, respiratory illnesses, and premature mortality.