WU Libraries Air Drying Procedures for Water Damaged Materials

Air Drying Procedures for
Water Damaged Materials

Initial preparations for air drying include the following:

Cordon off the affected area.
Prepare treatment areas by arranging tables with 5-6 foot aisles to allow activity, and by covering tables with plastic(black garbage bags are ok). Spread blank newsprint or paper towels on top of the plastic.
Collect portable fans and place them in aisles between tables. (Do not turn on fans until book materials are in place).
Begin moving damaged materials; if damage is "spotty", try to quickly sort 'wet', 'damp', and 'unaffected' materials. This avoids use of valuable treatment areas for undamaged materials.

After materials have been sorted, place each book on the prepared surface. Insert a sheet of paper towel between the leaves of a book every 20 leaves or so. The paper should not be placed all the way into the fold as this will lead to a buildup at the spine, which will cause the binding to fail. If the book is set on its tail (normal shelving position) arrange the interleaving such that it extends past the edges of the book at the fore edge and the head edge but not at the tail edge. This will provide an exposed area of interleaving paper while still allowing the book to stand safely.

Proper way to interleave-front view

Proper way to interleave-rear view

DO NOT DO THIS: Improper way to interleave

When books are soaked through, use unfolded paper towels to wick out as much water as possible. Change towels often.

Example of heavy interleaving

This interleaving paper serves as a wick to draw the water out of the book. Water will evaporate at the exposed edges of the interleaving, and as it does so, water from the interior of the book will move, by capillary action through the interleaving toware the exposed edges.

The boards (binding) of each book should be fanned open and the volume stood upright on the table. Often is is possible to place the books in such a position that they help to prop each other up. Frequently either the tail or the head of a book has absorbed more water (depending upon the source of the water). If so, turn the book so that the least weight is placed on the swollen area.

Place fans such that they keep air moving gently overall of the volumes without blowing them over. Sometimes this can be best accomplished by using large powerful fans and placing them at a considerable distance from the table. The fans must be left on around the clock until the drying is complete. If possible, air conditioning should also be left on continually.

As the interleaving paper become saturated with water, replace them with fresh interleaving. Try to place them between different pages than you did the last time. This is f the first interleaving was between pages (20-21, 40-41, 60-61...)the second should be between (30-31, 50-51, 70-71...), the third between (25-26, 45-46, 65-66...)and so forth. When the books are very wet, the interleaving will become saturated almost immediately and as soon as you finish interleaving a small group of books, it will be time to start all over again.

As the drying progresses, a stage will be reached at which the interleaving papers cease to wet out but merely become damp. At this stage, it is no longer necessary to replace the interleaving.

After the book feel dry to the touch, a condition that may take several days if the books were quite wet, remove the interleaving papers and leave the books fanned open, with the fans still running continually for several days. Paper can hold substantial quantities of water and still feel dry to the touch.

Line Drying

Used as either an alternative or a supplement to interleaving and air-drying, this process, in which a partially dried volume is suspended from thin monofilament lines, or placed on an indoor drier, line drying can help to avoid spine distortion caused by extreme swelling or excessive interleaving. The lines, no longer than 6 feet, are string 1/2 inch apart between two walls, tables, etc.

Line drying

This process is only rarely necessary and is not appropriate for heavy or saturated volumes. There should be sufficient lines (three or more) to maintain the proper shape of the spine.

Small, light v-shaped items, such as pamphlets and journals can be line dried on single lines, if the inner margins are not so wet that the line will cut through the weakened paper.

Link to Preservation page