Asbestos found in gym at North Bay high school

File photo (Photo by James Leynse/Corbis via Getty Images)

The presence of asbestos has been detected in a high school gym in Fairfield, school officials announced Wednesday.

Workers found a substance that could possibly be asbestos while conducting maintenance on part of the Armijo High School gym after examining a deteriorated piece of the wall. The substance tested positive for asbestos and the gym was closed "immediately," according to the Fairfield-Suisun Unified School District (FSUSD).

The district has called in an expert to encapsulate the affected area so that at least 80 percent of the gym can be re-opened, FSUSD officials said.

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Asbestos fibers are only harmful when airborne and breathed into the lungs. It is often found in buildings erected roughly between 1940 and 1970.

The exact timeline of the repair project is "unknown," according to the district. School administrators are currently working with the district to find alternative sites for Homecoming and sporting events, FSUSD officials said.

District officials did not know whether students have been exposed to the fibers or how long the wall had deteriorated to the point of exposing asbestos.