PAMAir shows many places in Hanoi reaching purple-warning level for air pollution. (Photo: VNA) Hanoi (VNS/VNA) - Air pollution in the capital city of Hanoi has risen to seriouslevels over the past two days.
AirVisual, aninternational air quality monitoring facility that generates data from public,ground-based and real-time monitoring stations, recorded on September 30 that Hanoicontinued to be the most polluted city in the world with the Air Quality Index(AQI) exceeding the red-warning level. It reached the purple level withAQI of 272 at 6.30am.
Hoang Duong Tung, Chairmanof the Vietnam Clean Air Partnership, said it was abnormal and neededcareful research to find out why, he said.
Tung warned that peopleshould limit morning exercises that would lead to them inhaling more dust.
He added that monitoringin the country remained limited. Hanoi has two fixed stations whereas Ho ChiMinh City has none.
Air pollution in Vietnamis caused by fine dust, specifically known as PM2.5, which is particulatematter that can be found in the air and is incrediblysmall. A single particle has a diameter of less than 2.5 micrometres.At this microscopic size, when inhaled, they penetrate directly into thebloodstream and travel to important internal organs.
Direct contact withPM2.5 can lead to serious respiratory, cardiovascular and neurologicaldiseases. A PM2.5 pollution index of 12 microgrammes per cubic metre isconsidered to be at a safe level. This index is equivalent to AQI level 50.
The AQI is a metric usedby multiple governmental agencies to determine how polluted the air is. An AQIlevel above 100 is considered polluted or unhealthy for humans. Children andpeople with respiratory and heart diseases are recommended to avoid outdooractivities when AQI levels reach 150 or above./.
VNA
