II. Procedures for Paper-based Materials

1. Priorities for Wet Paper-based Materials
2. Handling precautions for Paper-based Materials
3. Overview of Recovery Methods for Wet Paper-based Materials
4. Procedures for Freezing Wet Paper-based Materials
   1. Packing Materials to be Frozen
   2. Transporting to the Loading Dock
   3. Choosing a Freezing Facility
5. Procedures for Air Drying Wet or Damp Paper-based Materials
   1. Preparation of the Drying Site
   2. Air Drying Procedures
6. Cleaning Books
   1. Cleaning Precautions
   2. Cleaning Procedures

II.1. Priorities for Wet Paper-based Materials

• Freeze or dry within 48 hours to avoid mold growth and to minimize distortion
• Immediately freeze books with coated paper, keeping them wet until they can be frozen
• Immediately freeze books with leather and vellum bindings (unless a conservator can dry them right away)
• Work first on books that have fallen on the floor, coated paper, the wettest materials
• If books are wet and tightly packed on shelves, remove one or two so that they do not burst off the shelves as they swell (and incur further damage as they fall)

• Stable media - freeze or dry within 48 hours to avoid mold growth
• Soluble inks and pigments - immediately freeze or dry
• Coated paper - immediately freeze or dry

• Do not open volumes, or close those that have fallen open
• Do not separate covers from textblocks
• Handle one item at a time, using both hands
• Do not press water out of wet books--the paper is too fragile when wet

• Do not try to separate single sheets (except to air dry--see II.5.2 Air Drying Procedures - Separate Wet Sheets)
• Keep documents in order and retain documentary information
• Do not blot surfaces of documents that have soluble media

• Air Drying - Materials are dried by spreading them out on and/or interleaving them with absorbent paper in a work space in which the temperature and relative humidity are kept below 65° F and 35% RH, and fans are used to keep air circulating.
  Use for:
  • Damp books and books with wetness no more than 1" in on the edges
  • Small amounts of damp or partially wet unbound paper
  • Very few wet books, but only if staff are available to dry them in a controlled environment

    Don't use for:

  • Coated paper
  • Leather or vellum bindings (air drying should only be done by a conservator)
  • Large quantities of wet unbound paper

• Freezing - Wet materials are stabilized by freezing to allow time to plan for recovery. Freezing is an interim step. Materials must be air dried or vacuum freeze dried after being removed from the freezer. Mold will not grow, and further distortion is halted once materials are frozen. Rapid freezing minimizes damage from ice crystals.

• Vacuum Freeze Drying - After materials are frozen to prevent further distortion and mold growth, frozen materials are dried in a vacuum chamber. Materials remain frozen as water is removed. The water passes from a solid state (ice) directly to a vapor state.
  Use for:
  • Wet books and unbound paper
  • Coated paper
  • Soluble inks and dyes
  • Large quantities of damp books or unbound paper if staff and space are not sufficient to air dry

    Don't use for:

  • Leather or vellum bindings if they are important to save (these should be air dried under controlled conditions by a conservator)

• Vacuum Drying (vacuum thermal drying) - Wet or frozen materials are dried in a vacuum chamber. A vacuum is drawn, heated air is put into the chamber, and a vacuum is applied again to pull out the moisture. Books distort more than when vacuum freeze dried. A lower-cost alternative for materials of lesser value.
  Use for:
  • Large quantities of unbound paper without intrinsic value

    Don't use for:

  • Soluble inks and dyes
  • Coated paper

• Dehumidification - Materials are dried in place on shelves by large commercial dehumidifiers that are brought on site. Temperature and relative humidity in the area should be controlled. Books distort more than when vacuum freeze dried.
  Use for:
  • Moderately wet books

    Don't use for:

  • Coated paper
  • Leather or vellum bindings

• Freezer Drying - Materials are put in a freezer for months. Over time moisture sublimates out of the materials.
  Use for:
  • A few wet books

    Don't use for:

  • Coated paper

Books

• Wrap each volume (or every other) in freezer or waxed paper (coated side in). Wrap a single sheet around, open at the fore-edge. Wrapping keeps frozen books from sticking together and keeps dyes from bleeding from one book cover to another.
• Pack books spine down in milk crates or cardboard cartons lined with plastic trash bags. It is easiest to turn the box on one side, lay each book flat, spine in, then turn the box upright when it is filled. Full boxes are desirable because further distortion is inhibited, but if boxes cannot be gotten to freezers right away, do not fill them completely (wet books will continue to swell).
• Pack books that have fallen open as is (do not try to close). Lay only one open book on top of a row of packed books, with waxed paper beneath it.
• If feasible, charge books out (keep in mind that wet books should not be opened). Alternately, mark each box with the library's name, and number each one. Use tags or masking tape to label. Make a list of each box and its contents: call number range, number of volumes, and whether materials are wet or damp.

• Place manuscript boxes in milk crates or cardboard boxes lined with plastic bags. If time permits, interleave each manuscript box with freezer or waxed paper.
• If materials are not in boxes (wet boxes may have to be discarded) interleave every two inches of foldered material with freezer or waxed paper.

• In drawers - Sponge standing water out of map drawers. Remove drawers, then ship and freeze them stacked up with 1" x 2" wooden strips between them.
• Loose materials - pack in bread trays, flat boxes, or on plywood sheets covered in polyethylene. Rolled materials - bundle very loosely in small numbers.

II.4.2. Transporting to Loading Dock

• If boxes get wet, do not stack them--the weight may crush those below.
• Establish a route to the loading dock and mark the route with signs.
• At the beginning, transport only a few crates or trucks until a routine is established.

II.4.3. Choosing a Freezing Facility

Options are:

• Use local freezers (South Dining Hall is the 1st choice - we've used them before with success)
• Ship immediately to a freeze drying company
• Rent refrigerated truck(s)
• Hire freeze drying company to remove materials from the disaster site

If using a local freezing facility, two Team members shall drive the Libraries' van (obtain van from Facilities & Services, 5-9054) and unload materials at the freezing site.

• Identify a work space for drying in which the environment can be controlled (as in I.5 Stabilizing the Environment), and preferably with a large amount of table surface. If not, a floor will do.
• Cover the tables or floor with plastic sheeting. Lay absorbent paper on the plastic. If using floors, delimit drying areas with tape and leave aisles for access.
• Transport materials to the drying area either on trucks or packed as for freezing, depending on the quantity of materials and distance from disaster site to drying site.

II.5.2. Air Drying Procedures

Books

• Saturated books - Stand books on their heads; open only the covers slightly to allow them to stand. Lean two books together if they cannot stand alone (e.g., paperbacks), or support them with bookends. Change paper on table as soon as it becomes wet, and turn the book alternately to rest on head and tail each time paper is changed. When most of the water has drained, follow procedure for damp books.
• Damp books - Interleave absorbent paper every 50 pages starting at the back of the book, with interleaving extending beyond the tail and fore-edge (for standing on heads). Paper towels are best, but unprinted newsprint will do. Change interleaving as soon as it becomes wet, turning the book to rest alternately on tail and head each time. Frequent changes are better than too many interleaves, which cause further distortion.
• Final air drying step - When almost dry, lay books flat, reform them into their normal shape if possible, and place a light weight on top. Do not stack drying books together.

• Drying on a flat surface - Spread documents out on tables or floor in small piles on top of blotter paper. Spread out as much as possible and change paper beneath as it becomes wet. Interleave stacks of paper every 25 sheets with paper towels or other absorbent paper, changing interleaving when it becomes wet.
• Separating wet sheets - Place a sheet of polyester film on top of a stack of wet unbound papers. Rub gently with a bone folder - the top sheet will adhere to the film. Hang the sheets of film with paper stuck to it on a clothesline. As they dry, they will separate from the film. Or, lay the wet sheet and film on a sheet of polyester web (such as non-woven interfacing fabric). Carefully peel off the film. Lay another sheet of polyester web on top of the wet sheet. Lay these out on tables to dry.
• Final air drying step - Unbound papers may be flattened by placing them between two blotters and applying even pressure with weights.

II.6.1. Cleaning Precautions

• Cleaning is a secondary priority; salvage of wet materials is the first
• Cleaning requires careful handling. Staff should be carefully instructed before they are set to the task of cleaning.
• Opened volumes should not be washed.
• Always wear elbow length rubber gloves. This is a wet, messy process, so staff should also wear waterproof footwear.

II.6.2. Cleaning Procedures

• Hold books closed tightly enough to prevent dirt from getting into the textblock.
• Immerse in clean water, and agitate and/or dab very gently with a sponge. Brush covers only (very gently) with a small (2") paintbrush. Do not rub. Anything that does not come off by this method should be left, and removed after drying.

• Set up three plastic garbage cans filled 1/2 to 3/4 full with clean water in an area where running water is available so that water can be changed.
• Wash books as described above, passing books from one person to the next stationed at each trash can, until they are clean.

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