Preservation Myths Debunked
This week, Preservation Week 2014, we’re taking a cue from our blogging colleagues at History Myths Debunked, and debunking a pair of common preservation myths. Both anthropomorphize objects. Can you think of others to include for this topic?
“Artifacts need rest.”
We usually hear this in regards to textiles and the practice of rotating them on and off exhibit. Think of the artifact’s longevity in terms of a bank account, rather than a tired living thing, capable of rejuvenation. Light damage is cumulative and irreversible. Darkness itself does not re-invigorate that object in any way, although preparation for storage should involve proper vacuuming for pest management and padding out for support. Those benefits will be the only possible interest coming into the bank account. A textile’s appearance and fiber integrity will last finite amounts of time in a given light level—the more exposure, the less time. Each period of exhibition makes a withdrawal from the initial bank account. Rotation into storage will not reverse light damage but will save the remaining qualities of appearance (such as color) and fiber integrity.
“Artifacts need to breathe.”
Here’s what Jim Reilly, Director of the Image Permanence Institute, has to say about this one in his worthwhile article, “Ten Surprising Things about HVAC and Sustainable Environmental Management.” Citing regular “confusion about ventilation requirements for collections in storage,” he writes, “collections don’t need to ‘breathe’ in the sense that the objects need fresh air and oxygen just like living organisms do. In fact, reduced oxygen can even be beneficial to preservation for certain materials.”
“Ventilation requirements for collection spaces are determined by three main goals [bullets added]:
- ensuring good uniformity and mixing of air
- supplying sufficient fresh air for human occupants
- diluting any volatiles that may arise by out-gassing from collections or building materials
Experience has shown, however, that ventilation rates for collection storage are frequently much higher than they need to be to address these goals. Unnecessary fresh outside air and air circulation can work against sustainable operation, however. Many institutions have found that reduced outside air volumes and air circulation is a useful energy-saving measure.”
The breathing notion also often comes up when evaluating storage containers made from plastic vs. archival board. Trapping high RH in a micro-climate is a concern with plastic containers as are any plasticizing chemicals left over from the manufacturing process. Allowing the plastic to out-gas for one or more weeks before use and packing during a period of moderate RH are ways to mitigate the potential dangers of the sealed environment. A monitored and managed micro-environment can even be a preservation advantage for many object types.