High heat and humidity? Watch out for mold on books, paper

Worried about the books and papers in your office after a few weeks without air conditioning? You probably should be. 

To protect the physical collections in the Library, faculty and staffed moved every book to Clough Undergraduate Learning Commons. Luckily, it still had air conditioning. If not, they would have not been able to arrest the growth of mold on the more than 30,000 books. 

It could have been a disaster, meaning hundreds of thousands of dollars in losses for the Institute. Here’s why: Mold is bad for physical materials. This is why the collections in the Library’s offsite storage facility, the Library Service Center, stay at 55 degrees Fahrenheit and 35 percent relative humidity. Those settings keep the materials in pretty much perfect condition for the next 250 years. 

But back to campus: The high heat and humidity in campus buildings from the chilled water outage have made mold – which is ever-present no matter what -- very happy. When mold is happy, it grows and spreads. And that mold growth can mean serious health problems to the thousands of people who use the Library every day. 

The Library will be OK in the long-term. Faculty and staff are now in the process of cleaning any new mold growth on materials so the Library can open as soon as the chilled water outage is fixed. This includes cleaning shelves and tables with alcohol and vacuuming every inch of carpet. 

And once the humidity is back under control in your building, you’ll want to jump into action to protect your own cherished books. 

To clean books, here is a list of materials you’ll need:

• HEPA vacuum
• Cloth wipes
• Gloves
• Masks
• Ear protection (or a great playlist/podcast)
• Comfortable clothes/shoes

Since the Library’s books are currently in boxes, we first remove the books from the box. We vacuum the inside of the box on all sides and corners to get as many mold spores as possible that have fallen off the books. Then we turn our attention to the books:

• Hold the book tightly closed while cleaning.
• Vacuum the top and bottom of the book, sweeping away from the spine to avoid damage. 
• Then vacuum the entire outside of the book.
• Next, use the cloth to wipe the entire outside of the book.
• Vacuum again, just as you did the first time. The point is to agitate all the mold particles and vacuum them into the HEPA filter.
• Place the book back in the box and move on to the next.

What about papers? Unfortunately, cleaning single sheets is extremely difficult because of the suction. Instead, make photocopies of all your important documents and trash the originals. It’s a great way to clean out your office!

If you have any questions about your own materials, feel free to contact the Library.

We also recommend you check out this article from the Northeast Document Conservation Center, which specializes in treating and digitizing collections made of paper or parchment.