Guiyang, capital city of Southwest China's Guizhou province, reported some impressive results on March 11, when it released its air quality rankings for the month of February.
According to the rankings, the air quality in Shuanglong district ranked top, followed by Guanshanhu district, Wudang district and Huaxi district. Baiyun district reportedly had the lowest level in the category of excellent air quality.
This February witnessed the excellent rate of air quality ranging from 96.4 percent to 100 percent in Guiyang and in other development zones. Its composite index of air quality varied from 2.47 to 3.55.
Aside from Baiyun which reported instances of primary PM 10 pollutant, the major factor that influenced the air quality of the other areas was PM 2.5 - the fine particulate matter with a diameter of less than 2.5 microns.