Yellow dust created "hazardous" conditions in some areas of South Korea on Friday, according to the Korean Meteorological Administration and the U.S. military’s 18th Medical Command.
Dust levels registered 1,059 micrograms per cubic meter at Yongsan Garrison and 994 micrograms at Camp Humphreys and Osan Air Base.
Anything above 800 micrograms falls under the U.S. military’s highest dust alert status, hazardous, and all personnel are told to remain indoors and keep activity levels low.
The dust, blown across the Korean peninsula from Chinese and Mongolian deserts, may include heavy metals.
Camps Casey and Red Cloud showed a high of 624 micrograms, and Kunsan Air Base registered 724 micrograms.
By late in the afternoon Friday, levels in the north were steadily dropping, while dust levels at U.S. bases on the southern portion of the peninsula were on the rise.
At 8 p.m. Friday night, Camp Walker and Camp Carroll in Daegu were registering 242 micrograms; Gwangju Air Base showed 314 micrograms; and Camp MuJuk registered 101 micrograms.
Kunsan Air Base recorded unhealthy levels of dust at 332 micrograms Sunday but returned to low levels Monday.
Yongsan Garrison and other areas were hit with yellow dust storms exceeding 2,000 micrograms in 2006.
For updates on the latest yellow dust counts at bases in South Korea, go to http://www.seoul.amedd.army.mil/sites/yellowsand/default.asp.