Military training and all school activities were moved indoors at Chinhae Naval Base, South Korea, on Monday when yellow dust storms caused hazardous conditions, U.S. Forces Korea officials said Tuesday.

Earlier USFK reports on Monday indicated that training had not been affected in the midst of Key Resolve/Foal Eagle, an annual exercise that includes thousands of servicemembers on assignment from bases in other countries.

Chinhae yellow dust levels reached 1,190 micrograms per cubic meter at 4 a.m. Monday before coming down to acceptable levels later in the day.

At 800 micrograms per cubic meter, the 18th Medical Command’s Yellow Dust Web site recommends that everyone stay indoors and keep activity low.

“Our Seabees (naval construction sailors) canceled their outdoor projects and did indoor training,” USFK spokesman Col. Franklin Childress said in an e-mail early Tuesday.

Officials walked around base to make sure personnel minimized heavy physical exertion, Childress said. They also increased bus runs and suspended wear of body armor — a requirement for many personnel participating in the exercise — until 7 p.m. Monday, Childress said.

Yellow dust comes from the Chinese and Mongolian deserts and may include heavy metals from factories and development.

In a 2005 study conducted by researchers in South Korea, China and Mongolia, children from Mongolia exposed to the most yellow dust had lesser lung capacities than children living on Jeju island, at South Korea’s southern tip.

For yellow dust guidelines and real-time data on dust levels at bases throughout the peninsula, go to

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