Keeping it cool, dry, and constant

Contributed by Biff Hollingsworth, Collecting and Outreach Archivist

A few weeks ago, SHC Director Bryan Giemza and I traveled to the Mississippi Delta to discuss the preservation of several archival collections found in the area. During the visit I couldn’t turn my archivist brain off – I couldn’t help but ruminate on the physical environment around us, especially as it relates to the preservation of archival materials there. I realized that the Mississippi Delta is a very hostile place for paper!

Fresh from this experience, and since we often get questions from the public about the proper storage of personal and family collections at home, I thought I’d offer a few basic guidelines that I’ve learned from working in the field. And perhaps this is the best time of year to consider this, since it is a time when many of you are pulling out Christmas decorations from storage, clearing space in your closets for winter coats, or bringing out old photographs from your personal archives to scan for that awesome (or awkward?) DIY holiday calendar that you plan to give to all your loved ones this year.

IMG_3703
The sun beats down on the Delta – even in November.

Paper preservation experts, such as the Northeast Document Conservation Center and the preservation section of the National Archives, agree on three basic environmental factors for safe storage of documents, photographs, films and other treasures. The storage environment should be:

  • Cool,
  • Dry, and
  • Constant

Three things the Mississippi Delta is not! For example, look what the Delta’s hot and humid climate has done to the paint on the ceiling of one of the buildings that we visited during our trip.

IMG_3687

But how cool is cool? And how dry, and how constant? Well, documents and photographs are a lot like human beings. Both are “comfortable” in an environment that:

  • is about 60-70 degrees Fahrenheit
  • is kept at 40-50% relative humidity (RH)
  • has clean air and good circulation.

Temperature extremes and fluctuations speed up the chemical breakdown of paper that causes them to become brittle or discolored.  Also, excess moisture can result in mold growth and other archival nightmares.

So, where’s the best place in your home to store family collections? It certainly depends on specific environmental factors in your home, but often the best place to store family collections is in the interior part of the living space within your home, like inside a hall closet, where you know things will stay nice and cool, dry, and constant. Also, an added bonus of a hall closet is that collections stay in the dark, out of harmful sunlight.

Just remember: would you want to live in a leaky barn in the Delta? Or in a musty crawlspace under the house? Or in a hot garage?