TAIPEI - The largest sandstorm to hit Taiwan in five years sent air quality in Yunlin County, located in the central part of the island, to hazardous levels on Saturday (April 7), Taiwanese media reported, citing environment authorities.

Across Taiwan, air quality ranged from moderate to unhealthy, reported the semi-official Central News Agency.

The Environmental Protection Administration (EPA)'s station in the industrial area of Yunlin's Taixi township saw the Air Quality Index (AQI) hit the maximum level of 10 in the 10-tier indicator as of 10am.

That means that air's impact on health impact had reached "emergency" conditions, the EPA said according to the news agency.

Chang Shuenn-chin, a senior EPA official, attributed the poor air quality to sandstorm coming from China and strong winds in the region.

Wind speed had reached 14 meters per second, which was about the level of a tropical storm, Chang said.

Air quality might improve from Sunday onwards, after the cold air mass currently affecting Taiwan weakens, he said.

The EPA advised Yunlin residents to avoid outdoor activities and keep their doors and windows closed.