Nothing in the collections of SAAM is 17,000 years old, but a recent article in the Washington Post got me thinking about taking care of, and preserving, works of art. The article was about the cave paintings in the south of France, most famously Lascaux, and how mold was eating away at what could be the first recorded paintings in the world. The prehistoric paintings of deer, woolly rhinos, bison, and other animals have been the victim of fast-encroaching mold unknowingly brought inside the caves by visitors, scientists, and government officials. What looks like tiny marching ants but is actually fungal mold has appeared on the cave walls. The caves have been closed for twenty-five years while scientists and conservators try to remove the mold to preserve our ancestors' handiwork. A replica cave was created to accommodate tourists and even that seems to be having its share of troubles.
Closer to home, I checked in with the conservators at the Lunder Conservation Center at SAAM. After all, we do live in Washington, D.C. where summer temperatures remain toasty and heat and humidity are often problems in the care of art. According to Helen Ingalls, objects conservator at Lunder, "Mold growth is a continual risk when considering climate control. Of course, mold growth is a primary concern when natural disasters occur, and freeze-drying has been developed as an emergency treatment to forestall this potentially disastrous development. Fires and water-based fire suppression also bring the danger of mold growth to the museum world."
The objects at SAAM are well taken care of in terms of climate control; this goes for paintings as well as three-dimensional objects and works on paper. When the museum reopened, the most up-to-date computerized climate control system was installed. In terms of humidity, however, artworks of different materials pose different problems. The eighteenth century Santos figures from Puerto Rico--some of the oldest art in the collections--would most likely benefit from having a higher humidity to match their native EMC (equilibrium moisture content). However, the conservators don't dare to turn up the humidity because of the risk of fostering mold. Instead, silica gel cassettes that hold as well as expel moisture are stored in the base of the the object's glass case to keep the humidity just high enough, but not so high as to foster mold growth at 70-75% RH. Haven't you ever gotten to the bottom of a bag of chips or some food that is meant to stay crunchy, and found a little packet about the size of a package of salt you can pick up in a cafeteria? These, too, contain silica gel and work to keep moisture away from the food.
If you're concerned about taking care of art at home here are a couple of things you can do to avoid damage:
- Keep your paintings and other art objects out of direct sunlight. You can add light-filtering scrims to your windows.
- If it's valuable, there are three places in your home where art should not be stored: bathroom, attic, or cellar.
And in terms of heat and humidity, here's a climate litmus test courtesy of Ingalls: "If it's comfortable for people, it should be fairly comfortable for art."
Mold happens. But at SAAM, conservators do their best to make sure mold and other uninvited guests never have a chance to grow inside the building and compromise the objects.
