HANOI, Feb. 2 (Xinhua) -- Air quality in many areas of Vietnam's capital city Hanoi was at a very unhealthy level on Friday morning due to thick fog and high humidity, Vietnam News Agency reported, citing PAM Air, the country's private air quality network.
Air monitoring stations on Chua Lang street in Dong Da district, Sao Mai center in Thanh Xuan district, Doi Can street in Ba Dinh district reported an Air Quality Index of 263 to 265 (purple), showing health warnings of emergency conditions.
Thick fog over Hanoi's Noi Bai Airport on Friday morning delayed the takeoff or landing of many flights while at least six had to be diverted to other airports, VnExpress reported.
Many flights leaving other airports for Hanoi had to be delayed.
The Health Environment Management Agency under the Ministry of Health has warned people with a normal state of health to avoid outdoor activities for a long time when the air quality index stays at the very unhealthy level of 201 to 300.
Vulnerable groups are advised to stay indoor in this condition. ■
