Salvage of Water Damaged Library Materials - part 1

The Library of Congress

"Procedures for Salvage of Water Damaged Library Materials"
extracts from unpublished revised text, by Peter Waters,
July 1993


Since the first publication in 1975 of "Procedures for Salvage of Water-Damaged Materials" there has been no decrease in the frequency of accidents or unexpected disasters which have resulted in extensive water damage to library materials but there are many signs that we have begun to learn the immense value of disaster preparedness planning. Being familiar with the necessity of having to make a series of interrelated decisions promptly, understanding the effects of any particular course of action on subsequent ones -- this is the best kind of preparation needed in the event of major water-damage problems. A well-organized plan can greatly reduce the costs of salvage and restoration as well as the proportion of outright losses. This preparedness can also go a long way to lessen the emotional and stressful impact upon human beings.

The various courses of action discussed in this revised edition are designed to save the maximum amount of material with minimum amounts of restoration on the one hand or replacement on the other. However, it cannot be emphasized too much that no general instructions can take the place of an assessment of a given situation on site by a qualified, experienced library or archive specialist, who has proven experience in the reclamation of fire and water-damaged collections. It is strongly recommended that such assistance and advice be sought at the earliest moment after a disastrous event has occurred. In addition, the Conservation and Preservation Research and Testing Offices of the Library of Congress stand ready to serve as a technical information center and, if need be, a coordinating agency for emergency salvage efforts.

Library and archive staffs are now generally better informed about the mechanisms of drying cellulosic materials as well some of the technologies developed for this purpose. The use of vacuum chambers for drying large quantities of books and paper records has become an acceptable, almost common approach, but not without some confusion as to the differences and relative merits of vacuum drying and vacuum freeze-drying. Both methods effectively remove water but by quite different mechanisms and often with quite different results. An understanding of how these technologies function is essential in planning for a recovery operation, in order to make the best possible match between the nature, condition and needs of the materials and the capabilities of a particular drying system.

The use of fungicides to control the spread of mold growth has become an increasingly controversial subject because they may cause severe danger to workers and in some cases to the materials treated. Sterilizing by means of ethylene oxide and related chemicals has come under close scrutiny by the EPA, to the extent that we cannot recommend its use except by a commercial business firm which is fully insured and licensed to perform this service. Treatments involving the use of ethylene oxide (ETO), are best carried out under controlled conditions, as in vacuum chambers at the end of a drying cycle, and they must be guaranteed to leave no residual toxicity in the material. ETO remains the most effective treatment for severe mold attack resulting from major disasters, especially those exposed to river water.

The critical decisions that have to be made following water damage require knowledge of available drying technologies and their effects on a variety of composite materials. Ideally, materials removed from site, should be prepared and packed in a manner most suitable for the drying method to be used. Unfortunately, what tends to happen, particularly when no emergency plan exists, is that wet material is packed and shipped off to freezing facilities without knowledge of how the material will be dried. This may result in the material having to be re-packed before drying which adds considerably to the cost of drying and the potential for further damage.

The complete restoration of water-soaked documents, particularly bound items, can be a costly process even under the most favorable conditions. In the majority of cases, the high costs involved do not justify the salvage and restoration of books which are in print and can be replaced. However, decisions relating to these factors are virtually impossible to make during a salvage operation and even when a disaster plan exists. On the other hand it might be unwise not to attempt to salvage everything, if an insurance assessment is required and a claim is to be made.

Freezing, followed by vacuum freeze drying has been shown to be one of the most effective methods for removing water from large numbers of books and other paper records, but drying is not the final step in the reclamation process. In some cases, volumes which are only damp or which have suffered minor physical damage before freezing may come from a drying chamber in such good condition that they can be returned to the shelves. It is preferable that, where possible, the packing on site should be carried out in such a manner as to segregate very wet material from that which is partially wet and those that are damp from exposure to high humidity conditions This will not only result in cost savings during the drying operation but will help to avoid over drying of the least wet material. In the majority of instances, drying must be followed by restoration and rebinding, and therefore the technique and success of the drying method chosen will directly affect the final cost of restoration. This can be very expensive.

Thus, librarians and others faced with decisions which follow serious flooding and water damage from the aftermath of fire, and related water-damaged exposure, need to be reminded that replacement is nearly always much less costly than salvage and restoration. The necessity for making sound, on-the- spot, cost-effective judgments is the best reason for being prepared in advance by developing a pre-disaster preparedness plan. There are a number of such plans that have been drawn up, which can be found in the literature, to serve as models.

We encourage all of our colleagues who care about the integrity of library collections, including those who are difficult to persuade that a disaster could ever occur, to formulate disaster preparedness plans without delay so that it may never be necessary to refer to this document in times of distress!

Disaster Preparedness Table of Contents