This page addresses wet salvage of books during emergency response. More information about the conservation treatment of books can be found on the Book and Paper Group Wiki.
See also: Stabilizing Wet Paper and Stabilizing Wet Skin and Leather
Factors to consider[edit | edit source]
Books are largely made from paper, which can consist of a variety of fibers such as bast, cotton, hemp and wood. Fibers can be good or poor quality, coated, calendared, sized or unsized. All of these factors influence the way any particular piece of paper reacts to water.
Paper expands and contracts, and is 90% air and very absorbent. Art on paper can be made with a variety of media, and a variety of media may be present on any single piece of art. Paper has a grain direction, which can influence the strength of the paper when wet. There may be fillers present in the paper to increase the weight, density or strength, which can react unpredictably to water. Glossy paper may be coated with clay, which can cause serious, immediate concerns.
However, books are also composites of a number of other materials and types of materials, which all react differently to water depending on their composition, use and past storage conditions. They may also be constructed of unusual materials, such as leather or parchment.
In library contexts, books are usually shelved in a specific order and have metadata attached to them, often in the form of call numbers, barcodes, or shelf order. It is important to keep the cataloging information with the book, and, ideally, maintain the shelf order when moving the books.
What to expect when books get wet[edit | edit source]
- Old mends and bindings will release where adhesives are water soluble; the adhesive may move unpredictably through the rest of the book.
- Media and some binding materials may run or bleed.
- Books with coated pages will block (stick together) if they are not frozen or dried immediately.
- Pages will cockle and staining may occur; capillary action will wick up moisture and create tidelines.
- Mold growth is possible. Lower temperatures to slow mold growth if possible.
- Books can be very heavy and difficult to pick up without support or assistance. Books on a shelf may swell and be difficult and dangerous to remove.
Salvage priorities[edit | edit source]
The first salvage priority should be to dry or freeze unstable materials, such as bleeding inks, coated papers, or parchment. If the media or binding materials are bleeding onto other items, remove the bleeding items first.
Composite constructions such as items with metal fasteners, encrusted covers, or mixed media items are also salvage priorities.
All wet books, whether very wet or slightly damp, are prone to mold. If they cannot be immediately dried, they should be frozen immediately.
Replaceable books are low priority. However, do not assume that general collections items are inherently replaceable; as much as two thirds of an academic library general collection may be irreplaceable on the open market.
Do not attempt salvage until it is safe to enter the space; if there are health hazards such as raw sewage, wait until it is safe to enter the space.
Drying books[edit | edit source]
Most incidents involving a small number of wet books can be resolved via air drying. Stand the books up on a flat surface and fan the pages out. Keep the air actively moving with fans to increase evaporation. Interleaving a few pieces of clean If possible, portable units should be employed to lower the humidity to increase water evaporation. Lower the air temperature if possible, to reduce the risk of mold.
Air drying is not an effective option for books with complex or unstable structures. Freeze materials made with leather or parchment, and materials made with coated paper, immediately. These items should be freeze dried.
Freezing books "buys time". Note that storing very wet books bent out of shape, such as leaning, or directly against wire racks in freezers, will cause the book to deform, sometimes permanently.
Use carrying supports for large items or weak papers--again, paper becomes significantly--sometimes surprisingly--heavier when wet.
- Air dry actively moving the air with fans
- Freeze to buy time if necessary
- Use carrying supports for large items or weak papers
- Blot off excess water, be careful of sensitive media
- Air dry by fanning out pages
