Recovery of Wet or Damp Materials

Although speed is essential, the safety of staff and patrons is always the most important consideration. No one should enter the affected area until fire, police, or other emergency personnel have determined that the building is safe.

The process of salvaging wet or damp materials must begin as soon as it is possible to enter the area. Actual procedures will vary according to the extent of the disaster as well as the resources of the institution. A library or musem that can muster a large number of workers (paid or volunteer) and has access to suitable work space will be able to do more at the site than one with few workers and no available working area. However, if the number of items affected is more than can be handled in about 48 hours, some measures must be taken to stabilize them until they can be sorted, dried, copied, discarded, etc. Arrange for the emergency area to be as cool and dry as can be managed. Dry ice; can be used to keep wet items cool; to prevent sticking or burning, don't place it directly on the materials.

In the course of planning, priorities for salvage among the collections should have been worked out. During the response phase, the recovery team should arrange to take out important items first in whatever state they are. After that, materials can be removed according to how vulnerable they are to further damage. Always remove books or objects fallen to the floor first. Items which are easily replaceable or of minor importance to the collection are last. It is important to work methodically since it is quite possible that not everything will be saved.

The techniques on the following pages should be reviewed by everyone on the recovery team to make sure that they are truly within the scope of what can be done, given the actual situation. You may find that what seemed like a straightforward job at the beginning becomes more overwhelming as time goes by and people get tired. If it looks like it will not be possible to get the materials out of the emergency site and dried within 48 hours, call a recovery company right away.

AIR-DRYING BOOKS;

Air-drying is a possibility if there is enough help, a suitable work area and if the job can be largely accomplished within 48 hours. It is a good way to dry books which are wet only around the edges, as might happen in the case of leaks or sprinkler system discharges in stacks where books are tightly shelved. The work area must be kept as dry as possible with .i.air-conditioning;, .i.fans;, .i.dehumidifiers;, and by removing wet carpeting, packing boxes, towels, and other damp items frequently. A rough rule of thumb is that a library can handle about 500 wet or damp books in-house; this is by no means a hard rule so evaluate each situation.

Books should be stood on their top edges (upside down), on clean, absorbent surfaces, such as unprinted newsprint, blotters, large towels. The covers can be opened and the pages fanned out. Pieces of newsprint or paper towels can be inserted in the books every so often and allowed to stick up at the top to act as wicks. These have to be changed more or less frequently depending on how wet the book is. Very good directions for air-drying can be found in Peter Waters' Procedures for Salvage of Water-Damaged Library Materials,  included in A Primer on Disaster Preparedness.

COATED PAPER

Keep in mind that damp books with pages printed on .i.coated paper;can be air dried but only if they are interleaved at every page, or if the pages are fanned or turned frequently during the process. This is more likely to work with materials like pamphlets which are thin enough to allow all the pages to be interleaved without destroying the binding. Another possibility for pamphlets of one section is to remove the staples and separate the pages so they can dry on a flat surface. This is a good option if just a very few pamphlets are wet and there is sufficient space and personnel. When the leaves are dry, gather them together and put them into a large acid-free envelope, for later repair.

If books do dry before they are treated, the pages will stick together, but in cases where only the edges were wet, the books can sometimes be salvaged by having the edges trimmed off in the process of library rebinding.

Soaking-wet books with coated paper seldom air-dry successfully. For these, the best solution is to freeze as quickly as possible and then to vacuum freeze dry. For the initial freezing, any available freezer will do. If necessary, keep the books submerged in clean water to prevent them from drying before they can be frozen.

In general, air drying produces the greatest amount of distortion; in books. This is because books are made from a variety of materials that react differently to water and drying happens at an uneven rate, starting at the three open edges. Books will never be as flat as they were before, although rebinding will help. Major conservation treatment, including washing each page, resewing and making new covers will restore rare books to good condition. This is a very expensive undertaking. Keep these factors  in mind when deciding to air dry.

Unbound materials, on the other hand, often survive wetting and drying quite well as long as they are not allowed to become moldy.

PAPER DUSTJACKETS

Dustjackets on circulating books are usually considered expendable. But a book in a special collection is a different matter and an attempt should be made to save its dustjacket. Remove it carefully from the book; if muddy, place it on a piece of hollytex; (non-woven polyester web;), for support, and rinse it in a tray of clear water. Let it dry on an absorbent surface. If allowed to air dry on the book, the jacket will usually stick to the covers. The dustjacket may later be repaired by a conservator.

AIR DRYING DOCUMENTS

Loose documents, prints, .i.thin pamphlets; etc. can be dried by spreading them on clean absorbent surfaces in a secure area where there is good air movement and the humidity can be kept as low as possible. If they are muddy, first place each item on a piece of plexiglas for support and rinse it in a tray of clear water. Tilt the support to drain the water and debris away from the object. Do this only if you have access to clean water and enough trained workers; otherwise just concentrate on drying the materials. The documents or pamphlets can be covered with hollytex or plastic mosquito screening to keep them from blowing away, if necessary.

Don't attempt to flatten anything at this stage; simply try to get things dry as fast as possible. Flattening can be done later, if necessary, by a conservator. Damaged documents valuable only for the information they contain need not be dried completely, just enough so they can be handled and photocopied before they become moldy. This frees up drying space for other things. After copying, remove the damaged originals to avoid the risk of introducing mold into the file. Put the copies in acid-free folders and transfer the information from the old folders, taking care to preserve original groupings.

THIN PAPERS

Thinner papers often cling together when they are wet; don't attempt to separate these at the emergency site. Instead, take as many items as come away easily and support them by placing on a rigid surface. Be sure to bring out all folders, envelopes and wrappers found with the documents and keep them together. Once at the work area, they may be separated with the aid of a .i.microspatula;, shown at left, and spread to dry as described above. Microspatulas are available from conservation suppliers.

 Dry the folders, envelopes, etc. as well, and put the documents and their old enclosures into bigger folders or sleeves and then into storage cartons. Label the cartons and take them to the storage area.

MOVING LARGE WET OR DAMP PAPERS

When large, flat items such as prints ;or maps; are wet, they can become very fragile and may tear easily. Don't attempt to pick up such an item without some a support underneath. If the materials are in flat files, leave them in the drawers and use the drawers as trays, provided the weight is manageable. Heavy corrugated cardboard, plexiglas, bakers' trays, plywood and many other rigid materials can be used. If the make-shift tray is rough, dirty or otherwise likely to cause damage, cover it with polyester web, newsprint, blotters, even clean sheets or towels. Carry the item flat on its tray, between two people. Don't attempt to pick up a large item by yourself; work as a team with another person, for the safety of the material and your own.

Once the map or print is at the work area, remove it from the tray by picking it up by opposite corners. (See illustration).

Lay it on absorbent material to dry, face up. Don't attempt to wash mud or debris off anything larger than about 10" x 14" unless you have access to conservation equipment and training. Similarly, don't wash prints or any other art on paper or anything that's fragile. Fragments can be lost, colors can run and delicate paper can tear. If items start to curl as they dry, let them. When dry, put them in temporary storage containers of appropriate shape and size, label them and take the dry items to a secure, dry storage location until final disposition can be made.

ROLLED PLANS; OR DRAWINGS Drawings, rolled; Maps, Rolled;

If the items are in storage tubes, take them as they are to the work area. Place them on a large, steady surface and attend to them one by one. Open the container and observe the condition of the rolled plan. The tube or box may have prevented the plan or map from becoming really wet. In this case, it will probably come out easily. Save the information on the tube and keep it with the map. Discard the container and remove it from the work area. 

Work with a partner for efficiency and to minimize additional damage. If you can unroll the map at least partly, without causing damage, do so because it will dry much faster that way. You may need to place small weights (with pieces of blotting paper or paper towels under them) on various spots, to keep the map from rolling up again.

But if you notice that unrolling the map is causing damage, leave it rolled, as loosely as possible, and put it in an area with good air movement. Change its position from time to time and allow it to dry much longer than would seem necessary.

If a map is quite wet inside its tube, it may have swollen and may be difficult to extract. You may have to cut the tube apart (being careful, of course, not to cut the map.) Save any labels or identifying information on the tube and then discard the tube. Examine the map and proceed with caution. Unroll it if possible. Remove debris and blot excess water as necessary. As it dries, it may start to curl. If you would like to store the map flat afterwards, you may cover it with blotters and boards, provided you have the time, space and materials available. Change the blotters as they become wet.

BLUEPRINTS

These plans were produced from 1842 to the present by a photographic method. They will survive immersion in water that is not alkaline. Air dry them as described above; the same rules apply, but in addition, remember that exposure to light will cause them to fade. Keep them out of direct light during the drying process and always store in drawers, tubes or other containers that will keep them in the dark.

LINED MAPS

Large nineteenth century maps were frequently backed with canvas; this might have started to separate. The maps usually had wooden rods at top and bottom; they were attached with small nails. These might be coming loose so be alert for sharp points. Remove the map from the container, working as a team, and place it on a large surface covered with .i.Hollytex; over absorbent material. Unroll it carefully. Although a wet rolled map might not resist unrolling as much as a dry roll might, the wet paper could be very fragile and tend to tear easily. Work slowly, keep an eye on all parts of the map as you unroll it, and save any fragments that become detached. Replace the absorbent material as needed. Leave the map on the Hollytex support and pick up the support by all four corners to avoid tearing the map. When the map is thoroughly dry, it may not be possible to roll it easily. Store it flat if possible, but if not, put several layers of acid-free tissue, other acid-free paper, muslin, even clean bedsheets, over the face of the map and then roll it very loosely. Wrap in paper or muslin, label and take to storage area.

FRAMED ART ON PAPER; AND DOCUMENTS

Art or documents must be taken out of the frames for drying or they will mold. Attend to pieces on the floor first; they are a hazard to workers and in danger of being further damaged by broken glass.

Place the frame on a support, such as plywood, heavy cardboard, or plexiglas and move it to the work area. Lay it face up and examine the glass to see if it is cracked. Also try to notice if the art or document is sticking to the glass. If the glass seems sound and not stuck to the art, put the frame face down on a padded surface and remove the backing. You will probably need a flathead screwdriver and pliers from the disaster kit. Remove as many layers of wet matting and backing as come away easily. Don't attempt to separate anything that is stuck to the art. Save any backings or mats that have information. Place the art or document and any saved mats face up on absorbent materials on a flat surface and change the wet materials as needed. When thoroughly dry, put into boxes or portfolios, label, and take to storage area.

PARCHMENT; OR VELLUM; LEATHER

Books covered in leather, parchment or vellum and documents written or printed on parchment will become very distorted when wet. If there was a fire, put out by water, they will be especially damaged because these materials shrink in high heat.

Leather covers of books will probably not survive in a usable form. It may be possible to remove the covers and then air dry damp books. The books can then be rebound. If the books are quite wet, they can be freeze-dried with the covers in place and then sent to the bindery.

Parchment (or vellum) is a much more durable material than leather. The parchment covers of books can sometimes be restored by a conservator, so they should be retained. Dry them by a method that does not involve heat.

Parchment documents should be allowed to air dry. If framed, remove from frame as described above. Do not attempt to flatten them, simply dry them away from heat, to stabilize them. These documents can often be treated quite successfully by a conservator.

COMMERCIAL METHODS OF DRYING COLLECTIONS

There are various ways of drying materials. The choice will depend on the nature of the items to be dried and how wet they are, as well as the numbers involved and the extent of damage to the building.

DEHUMIDIFICATION

This is ideal for situations in which the building has suffered extensive flooding but the collections are merely damp. It is not suitable for sopping wet materials. The dehumidification company will seal off a portion of the building containing shelved collections and operate large dehumidifiers. Technicians measure the moisture content of books or other materials periodically to see when they are safely dry. This method has the advantage of leaving all the materials in situ and avoiding much costly handling.

FREEZING; AND FREEZE-DRYING

freezing, preparation forFreezing wet books and papers gives the institution a little more time to decide what to do. Paper will not mold or stick together while it is frozen. Any insects which might have been drawn to the wet objects will be killed. .i.Smoke odor; is often greatly reduced. Materials can be frozen in a large home or institutional freezer or taken to commercial freezers. They will be in a state of suspended animation until further action.

After freezing, the materials can be .i.freeze-dried; by a salvage company specializing in this technique, or they can be thawed out in manageable batches for air-drying.

FREEZER DRYING

If there is only a small number of books or documents that are damp or wet, they can be frozen in an automatic defrost-type freezer, either home or commercial, with the temperature set at -10░F. They will have to be kept in the freezer weeks or months, depending on the thickness of the books and how wet they were. Books with coated paper may stick if they had started to dry before they went into the freezer. Documents can be separated into thin stacks to speed up the process.

 VACUUM FREEZE-DRYING

This is the most satisfactory method for drying large numbers of wet books and records. It is the most successful way to recover materials printed on coated paper or containing water soluble inks. The materials are first frozen and then placed in a vacuum chamber where drying takes place at temperatures below 32░F. In this way, materials dry directly from the frozen state and never become wet again from thawing.

Vacuum freeze-drying produces the least swelling and distortion of cloth book bindings of any currently used method. This means that more books will be usable after they are dried, without needing rebinding. They will be close to their original size, so less additional storage space will be needed. Leather bindings may not survive this method, these books would require rebinding.

VACUUM THERMAL DRYING

This method can be used for books that are wet or frozen. The materials are put in a vacuum chamber and heat is used to raise the temperature to slighly over 32░F. This method is much less expensive than vacuum freeze-drying but it produces much more distortion and swelling. Books will need to be rebound and the text blocks will be more swollen than with vacuum freeze-drying. Coated paper will always block and photographic materials will be destroyed.

PREPARING MATERIALS TO BE SENT TO FREEZERS

Research materials can be frozen in various ways. While opinions differ on the optimum temperature, most authorities agree that fast freezing will give better results than slow. The library salvage companies that freeze materials do it quickly and at quite low temperatures but other types of freezing facilities can be used if economy or availability dictate. Even if the materials were to be ultimately vacuum freeze-dried, it might not be possible to get them to one of the specialized facilities quickly enough. In that case, local frozen storage would allow the library or archive to make decisions without so much pressure. The important thing is to get the materials frozen before they start to mold; or dry. (click here, for freezer storage facilities in the Hudson Valley.) If the quantity of wet books or other materials is not too large, one or more home or institutional freezers might do. They should be set to -10_F, or lower if possible.

The response team must determine how the materials will be transported. Some salvage companies supply .i.boxes ;or.i.milk crates;. In other .i.plastic crates;cases, the institution must supply them. Plastic milk crates are good for transporting wet materials because they don't get wet and fall apart, they have convenient handles, can be stacked safely, and their relatively small size means they will not get too heavy to move. .i.Corrugated boxes,; up to about 1.5 cu.ft. capacity, can certainly be used. Line them with large plastic bags to prevent the wet books from soaking the boxes. Then tape shut and label.

In addition to containers, the salvage company might be able to supply labor for packing, as well as moving equipment, trucks and many other useful items and services, not the least of which is good advice. The firms listed here have been in business for many years; their staffs have accumulated a lot of practical wisdom.

Books should be packed spine down, in one layer, or else flat. If there is time, wax or freezer paper can be wrapped loosely around every other book to prevent them from sticking together. If time permits, very .i.muddy books; can be rinsed either by dunking into containers of water or by spraying gently with a hose before packing. Distorted books can be gently realigned, but they should not be forced back into their original shape (this is impossible anyway). Keep in mind that books will emerge from freezing in pretty much the same condition that they went in. The packing process should be carried out as quickly as possible; in a large disaster, this is not the time to sort because books and other materials will start either drying or molding. However, workers must realize that paper is weak when wet. If the disaster consisted of a fire, put out by water, the affected materials will be especially fragile because of the combined effects of heat and wetting. So all reasonable care should be used in order to minimize additional damage.

Documents in file cabinets can be sent to the freezers right in their drawers. Be careful of overstuffed file drawers: as the wet paper swells, it will become impossible to open the drawers so it's a good idea to attend to these quickly.

When packing folders into boxes or crates, tilt the container or lay it on its side so that the folders don't need to be supported as they are loaded.

Materials in flat files can be sent to the freezers in the drawers, or they can be supported as described above.

Label the boxes or crates with waterproof markers. (Be careful when using markers around books or other materials). A disaster team member should be in charge of keeping a record of what materials are sent where. Although it is not possible or desirable to do any fine sorting at this stage, anything that is to be discarded should be saved until the insurance company or the proper administrator has observed the damage. Note what books or materials are being discarded; later, the library can decide whether those items can or should be replaced.

CLEANING MOLD ON BOOKS

If mold is found growing on books and other materials that were not affected by flooding, it means that environmental conditions are favorable for growth. These include high humidity, high temperatures, darkness, still air and undisturbed dirt.

If the mold is still confined to the covers of books or outer containers of other materials, the outbreak may well be curtailed by cleaning the visible mold from the materials and then carefully disinfecting the shelving.

Workers should protect themselves against exposure to the mold by wearing goggles and an appropriate, snug-fitting face mask or respirator. Face masks should be fitted by the institution's Health and Safety Officer. Hair and clothing should be covered with smocks, aprons, hats or caps that can be disposed or washed in bleach at the end of each session. Work clothing should be changed after each session, placed in plastic bags or other tight containers and washed or discarded. Workers can wear well-fitting cotton or plastic gloves. Avoid touching the face with dirty hands or gloves. Shower and wash hair after each session or, at least, before going to bed. Mold does cause a variety of allergic reactions in different people. Persons with respiratory problems should consult their physicians before doing this work. Staff should take frequent breaks in well ventilated areas or outside. Provide workers with snacks, happy music and any other cheerful amenities that will keep morale up.

Thoroughly examine nearby shelves to make sure that the mold has not spread there. Staff should learn the difference between mold and dust: mold tends to grow in uneven patterns or in little dots. It is just as likely to appear on horizontal surfaces as on vertical areas. Dust is even, and always thicker on horizontal surfaces. If uncertain, use a magnifying glass to look at some genuine dust. Then look at the suspected mold. A web of little hairs or plant-like growth with spores indicates mold. A mycologist should be consulted to identify the particular strain and determine whether unusual health risks are involved. You can get the name of a mycologist from a local college or hospital.

MOLD CLEAN-UP PROCEDURE

Cover unaffected ranges with plastic sheeting. Tape the film to the edges of the bookshelves. Close or block HVAC vents in the affected area to cut down on the spread of air-borne spores to other areas of the building. Lower the humidity by using dehumidifiers and increase local air circulation with fans or air movers. Or open windows, if feasible, when the humidity is lower outside than inside, and use exhaust fans. You may need to rent commercial equipment.

Pack the moldy books into disposable cartons, or transport them out of the library on book trucks that can be disinfected later. If there is a heavy infestation, the books should first be vacuumed. Use a wet/dry .i.vacuum cleaner, wet/dry;vacuum cleaner and place a bleach solution (four parts water to one part .i.bleach;) or other non-toxic .i.fungicide; in the holding tank in order to catch the spores. A vacuum cleaner with a HEPA.i.vacuum cleaner, HEPA; filter will do a much better job of trapping spores and is more convenient than a wet/dry vac. Use the brush attachment and, if the books are fragile, place a piece of cheesecloth between the brush and the wand to catch any loose pieces. The vacuuming can be done as the books are removed from the shelf or in the area where the major clean-up will be done.

The next step is to wipe the mold off bindings and edges of books. Use a soft cloth, such as flannel rags or One-Wipe cloths; (available from supermarkets) or DustBunnies ;(available from conservation suppliers). Mold spores are destroyed by alcohol. If the clean-up area is well ventilated and workers are wearing respirators, rags may be moistened in ethanol or isopropyl alcohol. Wipe all the surfaces of the book. Don't open books at this stage, to avoid getting mold spores inside. When cleaning the tops of books, work from the spine out to the fore edge.

Chemical sponges;, such as Gonzo sponges;, are always used dry sponges, chemical; and are excellent for removing mold. Slice some sponges into sections about 2" thick to make it easier to work on curved areas of books. As the surface of the sponge gets dirty, slice it away. (A serrated knife or scissors can be used.) The sponges can be used only on dry materials.

Take the cleaned books to a well ventilated, clean, dry (below 50% RH), area. Stand them fanned open. With clean hands, spot check for signs of mold inside. Let the books stand open for several days. This will reduce humidity in the pages to safe levels.

In the meantime, the shelving, walls, floor, etc. should be disinfected with a fungicide such as Lysol liquid or .i.bleach; (four parts water to one part bleach). Do not use great quantities of aerosols such as Lysol spray without protecting the worker with a properly fitted organic vapor (cartridge) respirator. Liquids are economical and more effective.

Carpeting; should be cleaned with a fungicide; added to the water. Remove the bottom shelves if necessary to gain access to the space below each range. In cases of recurring infestation, it is usually necessary to remove carpeting and install flooring that can be mopped clean. Carpets are excellent breeding places for mold.

Examine the cleaned books. If there are still traces of mold on the covers but not on the pages, the best solution is to send the books to the bindery for recasing. In the case of rare or historical books that must be retained in their bindings, consult a conservator.

 When the shelving and books are clean, carefully remove the plastic from nearby ranges and inspect these books again to make sure that they did not develop mold during the clean-up. The cleaned books can be reshelved.

 PREVENT FUTURE MOLD OUTBREAKS

After this is done, the most important task is to make sure that the conditions that caused the mold outbreak are corrected. This is critical because books that have once been moldy are more likely to get moldy in the future than books that have never been moldy.

Library guidelines indicate that HVAC should run 24 hours per day, 365 days per year in order to maintain humidity below 55%. A book collection that has never had a mold outbreak can usually ride out a period of humid weather without problems, but once there is a history of mold it really is critical to monitor humidity. This must be done not only in the summer but also during the cool, damp months in spring and fall. At this time it may be necessary to run heat and air-conditioning at the same time in order to achieve a safe level of humidity. Good cleaning practices and adequate air circulation are also key factors in preventing a future occurrence.

It may be a good investment to hire an HVAC engineer for a consultation. Referrals can be obtained from the American Society for Heating, Ventilation and Air Conditioning Engineers (ASHRAE;).  

MAJOR MOLD OUTBREAKS

More extensive mold outbreaks will require quick action by a disaster response company. They may bring in dehumidification equipment so that whole rooms and the materials in them can be dried enough to retard mold growth. The institution's staff or a cleaning company will need to clean the mold off books, walls, floors, shelves and other surfaces. The HVAC ducts should be cleaned and filters changed.For campanies that can provide dehumidification and labor click here.

Another method is to freeze books to stop the mold damage and postpone the cleanup until a more convenient time. A few books can be wrapped in plastic bags and frozen on site; larger numbers will need to be sent to a commercial salvage company. Freezing does not kill mold spores, but does make them inactive.

Good results have been obtained by the use of a fairly new technique. It involves enclosing the affected materials in a container with very low oxygen atmosphere. This can be done on site or by specialist companies, such as Art Care International, Inc.

For further information, contact a conservator or a regional conservation center. Both NEDCC and CCAHA can provide technical advice and literature.