Taipei, Feb. 17 (CNA) The air quality in central and southern Taiwan and the offshore county of Kinmen was unhealthy for sensitive groups -- orange on the six-color scale -- Friday while the eastern part of the country enjoyed good air quality (green).
For the rest of the country, the air quality was yellow, indicating "moderate" or the second best on the scale from green to maroon, according to the Environmental Protection Administration's Taiwan Air Quality Monitoring Network (http://taqm.epa.gov.tw/taqm/en/AqiForecast.aspx).
For Saturday, the air quality in the Kaohsiung City and Pingtung County is forecast to worsen to red, a level that is unhealthy for the general public, while central Taiwan and the rest of southern Taiwan are expected to see orange-level air quality, according to the network.
The only region to have good quality air Saturday will be Hualien and Taitung Counties in eastern Taiwan, with Yilan County to the north and Keelung, Taipei, New Taipei, Hsinchu and Miaoli seeing moderate quality air.
The EPA's color scale takes into account ozone, PM2.5 and PM10 particulates, carbon monoxide, sulfur dioxide and nitric oxide concentrations in the air.
Green represents "good" air quality, with a pollutant reading of less than 50; yellow indicates "moderate" at 50-100; orange means "unhealthy for sensitive groups" with a reading of 101-150; red indicates "unhealthy" with a range of 151-200; purple signifies "very unhealthy" with a level of 201-300; maroon represents "hazardous" with an reading of 301-500.