(Excerpts and adaptations from the University of Pittsburgh Library System
Consult with Physical Plant and Fire Marshall before proceeding with
- Turn off and unplug computers or other electrical equipment.
- Turn off water.
- Turn off the heat. If possible turn on the air conditioning and leave
it on without interruption for at least 2-3 days. Turn on fans and dehumidifiers.
The principal enemy to collections in a water disaster is mold, which
can develop within 48 hours in a warm, damp, and stagnant environment.
If conditions are more severe, it will establish itself in a shorter
period. Mold growth will be discouraged if the environment is kept as
cool and dry as possible with good air circulation.
- Remove water on floors or in carpets with wet-dry vacuums or carpet
- Remove damp or wet curtains or carpets.
- Be aware of potential electrical hazards. If the main power needs
to be turned off, fans should be run from generators to avoid fire or
danger to staff.
In any flood, damage and loss are inevitable. Some materials will be
permanently disfigured, whether cosmetically or structurally. The object
of a salvage effort is to recover the collection as a whole, while minimizing
damage. The Disaster Response Team should not spend too much time on single
items or small groups of items at the expense of the collection.
If the disaster is widespread, or includes more than 4,000 items, immediately
remove from the flood site high priority materials. Remove materials that
are highly vulnerable to water damage. Immediate attention should be given
to photographic materials, such as collodion wet plate negatives, ambrotypes,
panotypes, or tintypes. Wet materials printed on coated paper (shiny),
should be frozen before the paper dries and should not be allowed to dry.
The surface layer of the adhesives and other substances on coated paper
can cause adjacent pages to bond together when wet. When this effect,
which is known as "blocking", occurs it is virtually impossible
to reverse. Pages will be permanently fused together and will be very
difficult to separate. Vacuum freeze-drying is the most effective way
to avoid blocking. If mold has already developed, there is little likelihood
that the material can be air dried, and it should be frozen immediately
Assessing the wetness of the materials
Remove the most saturated materials first. These are not only likely
to be the ones most in need of attention, but since they hold substantial
quantities of water, their removal will help a great deal to lower the
ambient humidity at the flood site. The upper most or lower most shelves
will be the wettest, depending on the source of the water. The longer
the books have been exposed to water, the more pronounced these indicators
will become. The following visual clues are good indicators of water content:
swelling of the textblock and binding; deformation of the binding; cockling
of the paper or board; darkening of the color of the paper, cloth, or
leather.Swelling is an especially good indicator of the length of exposure.
The various parts of the book will swell at different rates as it continues
to absorb water. The textblock will swell the most and push out against
the less expansive case and the sewing thread, which may even shrink.
This results in a tendency for the spine to assume a concave configuration;
the longer the book sits, the more concave it becomes. When sitting in
a pool of water for a few days, some books swell to such an extent that
the spine forms a tight backwards circle and the front board touches the
rear board. Some tightly shelved books may swell to such a degree that
they "walk" themselves off the shelves. Swelling will usually
reach its peak after a few days.
When over 100 items are water damaged it is generally not practical to
air dry these materials on-site. If this is the situation, the materials
should be frozen as quickly and safely as possible. Proper freezing at
very low temperatures will stabilize materials physically and chemically
by preventing the development of mold; the further swelling of paper and
boards; the bleeding of inks; and possibly the blocking of pages. Most
importantly, freezing buys time, which allows one to plan the salvage
effort sensibly, without having to operate under crisis conditions. Books
and papers can be frozen indefinitely without damage.
Recovery of Paper Media
Handling Procedures: Wet paper has very little strength and easily tears.
Do not attempt to open a very wet book. The pages of a wet book cling
together and an attempt to open it may result in serious tears. Moreover,
damage to the binding can occur. If the book is only damp, it is usually
safe to open, though this is not necessary unless it is to be air dried.
Do not attempt to close a wet book that has been found lying open, as
often happens when books walk off the shelves and fall into standing water.
Such books are usually badly swollen and the pages may be temporarily
Mud, Silt, & Dirt: Generally it is not a good idea to attempt to remove
mud or other debris at the flood site, but rather to allow them to dry
and brush them off later. However, if the materials are extremely dirty
or the contaminants areparticularly noxious or toxic , it may be necessary
to wash off the covers of the book before further treatment. This is best
accomplished by holding the book closed and exposing the spine to a slow
stream of water, with the fore-edge pointed down so that the water runs
off the case without further wetting the paper. On occasion it may be
necessary to wash contaminants from the paper itself, in which case extreme
care should be taken. This task should be performed as quickly as possible.
Books that have been washed should be frozen immediately. Rare materials,
art on paper and other unique items may need to be treated in different
Disbinding: In a small scale emergency when attention can be paid to individual
items, it is on occasion, appropriate to remove the textblock from its
case. This may be appropriate when the textblock is swelling severely
and is being distorted by the case, or when mold has begun to grow in
Drying Methods: If you need time to make decisions or remove large numbers
of materials from the disaster site, books and documents should be frozen
to reduce physical distortion and biological contamination. Four methods
for drying materials are summarized below:
- Air Drying: Very time consuming, labor intensive operation,
which is most suitable for small numbers (less than 100) of damp or
slightly wet books or documents. It is seldom successful for drying
coated paper, such as the sort of paper found in many art books or journals.
- Dehumidification: The newest method used to dry library materials
and is appropriate for drying damp to moderately wet books, documents,
equipment, and furnishings. Dehumidification must be initiated within
24 hours before swelling or mold develops. It should not be used for
drying coated paper. Large commercial dehumidifiers are brought into
the library with all collections, equipment, and furnishings left in
place. Temperature and humidity can be controlled to the customer's
specification. The advantage of this method is that materials can be
dried in place on the shelf or in storage boxes. The time and expense
of removing materials to a freezer or vacuum chamber are eliminated.
- Freezer Drying: This method is most successful with books and
documents that are damp or moderately wet. It is important to freeze
the materials as quickly as possible to reduce distortion and facilitate
drying. Until the items are frozen through to the center, the freezer
temperature should be -10 deg. F. or lower to encourage the formation
of the smallest ice crystals. After this state has been achieved, the
freezer temperature can be raised to around 0 deg. F. so that some drying
can occur. Home freezers are usually not cold enough to achieve rapid
freezing, but may be used at the lowest possible temperature setting,
if more suitable equipment is not available. Frost-free units are preferred
since they will begin to dry the materials, albeit slowly. Materials
should be placed in the freezer as soon as possible after water damage
has occurred. Books will dry best if their bindings are supported firmly
to inhibit swelling. Manuscripts or unbound materials may be placed
in the freezer in stacks or spread out for faster drying. In very large
commercial freezers these materials may be left in their storage boxes,
however, this will slow the drying process. Depending on the freezer
temperature and the extent of the water damage, this method will take
from several weeks to several months to dry materials.
- Vacuum Freeze Drying: Vacuum freeze drying is a commercial
application of a physical phenomenon called "sublimation".
Frozen materials are placed in a vacuum chamber. The collections are
dried at temperatures below 32 deg. F. through a process called sublimation,
in which ice crystals vaporize without melting. This process is very
effective in drying large quantities of wet books and paper records.
Vacuum freeze drying will not cause additional distortion or swelling
beyond that incurred before the materials were placed in the chamber.
Coated paper will dry well if it has been frozen or placed into the
chamber within 6-8 hours. Rare and unique materials can also be dried
successfully with this method, but leather and vellum bindings may become
distorted. It is also effective with water soluble inks and pigments.
Vacuum freeze drying also lifts mud, dirt, and soot to the surface,
making cleaning less time consuming. Although this method may initially
appear to be more expensive due to the equipment required, the results
are often so satisfactory that additional funds for rebinding or recasing
are often not necessary.
Recovery of Non-Paper Media
Priority: Dry immediately
Handling: Drain & carry horizontally
Packing: Face up without touching painting layer
Drying: Air dry; Consult painting conservator
COMPUTER MEDIA: Prevention is the best insurance against
loss. Make backups & store off-site. Equipment may be damaged trying
to copy contaminated tapes or disks.
Priority: Dry immediately
Handling: Do not touch disk surface with bare hands
Packing: Contact supplier for best method
Drying: 1. Cut edge of jacket with non-magnetic scissors for floppy
disks or pry open plastic disk cover for flexi disks; 2. Remove disk with
gloved hands; 3. Wash in several photo trays of distilled water; 4. Dry
with lint free towels; 5. Insert into new jacket or disk cover
Priority: Dry immediately
Drying: Please follow these instructions to air dry: 1. Rinse tapes in
cold distilled water; 2. Support vertically; 3. Clean by winding against
a felt pad; 4. Copy tape and discard damaged original
Packing: In drawers or cartons
Drying: Air dry
Priority: Freeze or dry within 72 hours
Packing: Keep wet inside a container lined with garbage bags until drying
Drying: Air dry
Priority: Rewash and dry within 72 hours
Handling: Do not remove from boxes; hold cartons together with rubber
Packing: Fill boxes with water and pack (in blocks of 5) in a cardboard
box lined with garbage bags.
Drying: Arrange for a microfilm processor to rewash & dry within 72
hours; label box "Wet Film".
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