A good case study in microbiology of the built environment: Mold outbreak closes rare book section at Boston Public Library – The Boston Globe by Andrew Ryan
Some key bits are quoted below:
A significant mold outbreak has forced the Boston Public Library to close its Rare Books Department for five to 10 weeks after staff found fuzzy white spores on a medieval manuscript and other prized items in the renowned repository for ancient publications and artifacts.
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Mold outbreaks are driven by humidity, which can be hard to control in an older structure such as the McKim Building, which was completed in 1895. The Rare Book Department relies on the building’s central air conditioning system. The staff also monitors humidity and deploys dehumidifiers to combat dampness.
Mold spores can grow quickly. If the relative humidity surges above 70 percent for more than two days it can be enough to cause an outbreak, according to Michele Brown, a Cornell University book conservator who studies mold in libraries.
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The library is in a constant battle against humidity, she said, and “there are, routinely, mold outbreaks that have been handled through isolation and containment.”
Definitely worth a read.