Defining the Issues | Common Preservation Problems | Preservation Solutions | Further Information | Self-Assessment #13
Defining the Issues
Preservation and conservation refer to the processes of monitoring the physical condition of the library’s materials and taking action to prevent further deterioration. Preservation issues can be defined as those that relate to the longevity of materials, while conservation issues include handling and storage (although the terms “preservation” and “conservation” are sometimes used interchangeably or defined differently). Ironically, books published since the beginning of the 20th century are more likely to decay than older books (due to the paper and methods of binding used). (Johnson, p.101) Other modern materials such as microfilm, photographs, videotapes and films have unique preservation needs.
The best time to begin addressing preservation issues is when ordering materials where preservation is likely to be an issue. When possible, it is a good idea to buy the best quality materials available (see this section’s discussions on brittle paper and handling for some convincing evidence) if the item is likely to be one of the few things the library will wish to keep for a very long period of time. Under a tight budget, some compromises have to be made, but if you anticipate high use or lots of potential damage it may be better to spend a little more on the purchase, since repair and/or replacement costs may be avoided. However, in today’s fast moving information and publishing environment, permanency is the exception for most the public library collection. Even university libraries often prefer to purchase paperback editions of books that are likely to have a short life of real use and then may sit on the shelves for years without being touched. It is sometimes difficult to determine exactly what materials will need extra attention at the outset. Given the labor costs within the library, it is important to re-enforce or in other ways give extra attention only to materials that are truly in need of such attention. Enforcing the bindings on all paper bound books may not be necessary but determining which ones will need extra work is a judgment call. The vast majority of the stock of our public and school libraries is quite disposable. There is no sense preserving things whose shelf life is limited to a few years.
This section discusses some of the most common preservation and conservation problems faced in a small library (such as climate control, insect, mold and mildew infestations, and brittle paper) and common techniques used to handle these problems (such as book handling, repair and non-print preservation). Procedures for book repair are not discussed since they are beyond the scope of this training guide, but sources of further information are provided.
Common Preservation Problems
Libraries of all types face several kinds of preservation problems. Some of the most common ones for small libraries relate to climate control, biological pests, and brittle books.
The three most important factors in environmental control are humidity, temperature and light. Unless you have the opportunity to design a new building or make substantial changes to an existing building, some of these factors will be beyond your control, but it is still a good idea to work toward the best possible conditions.
Temperature and humidity
According to Library of Congress preservation recommendations, an ideal environment for books is 55° F in storage areas and not more than 75° F in reading areas (below 70° F is better), with relative humidity levels at 50 percent. Very low humidity can cause paper to deteriorate, while high humidity encourages the growth of molds and mildew. Books deteriorate more rapidly at higher temperatures and with drastic changes of temperature and humidity, such as when air conditioning is turned off at night and on weekends. While utility costs may make it impossible to keep the library cool 24 hours a day (especially in the Arizona summer!), some effort should be made to avoid “roller coaster” cycles of temperature and humidity. (Evans, p. 462-263)
Both natural light and artificial light (especially incandescent lights) contribute to heat buildup in the building. Yellowed paper and faded inks are due in part to light exposure, particularly ultraviolet radiation, the most damaging form of light. UV rays are present in sunlight, fluorescent and tungsten lights, so whenever possible lights and windows should be fitted with ultraviolet filters or drapes. It can be quite difficult to protect the collection from the effects of sunlight in buildings with many windows. Non-print materials are particularly sensitive to the effects of ultraviolet light, so videotapes and microforms should never be shelved near a window! (Evans, p.464)
In addition to controlling the environment, it is important to minimize (or eliminate) biological pests from your library. Some common pests include insects, molds, and mildew.
Book worms (larder beetle larvae) are not the only organisms to find libraries appealing. Other common pests and their favorite meals include silverfish (wood pulp paper, flour paste and glue), cockroaches (anything, but especially book glue), termites (wood, with wood pulp paper as a second choice) and book lice (starch and gelatin sizing on paper), among others. With so many delicacies stored on your shelves, how can you avoid being overrun? When possible, keep insects out of the collection in the first place. Discouraging food and drink in the library is a good start. Carefully examine any gift items for insects (and mold and mildew, for that matter) before placing them in the collection. Another strategy is to keep the temperature and humidity as low as possible. Shifting the books on the shelves may deter some infestations. Be sure to clean along baseboards, in cracks and anywhere else dirt and insects could hide. If you start to see significant numbers of insects, don’t hesitate to call in professionals who can get rid of your unwanted guests safely and effectively. (Evans, p. 465)
Molds and Mildew
Molds and mildew are another form of biological hazard in libraries. Arizona libraries probably don’t contend with mold and mildew very often, considering how dry our climate usually is! However, if conditions are right - warm temperatures, relative humidity of 70 percent or higher, darkness and poor air circulation - the mold and mildew spores that are always present in the air will begin to grow. Certain kinds of organisms may prefer paper, leather or photographs. A clean, well-ventilated and climate-controlled environment goes a long way toward preventing infestation by any of these pests. (Harvey, p. 45)
Acidic wood pulp paper, which typically has short fibers that make the paper weak and acidic residues from the manufacturing process that cause it to deteriorate rapidly, is to blame for brittle pages. (A page is considered brittle if a corner breaks off when it is folded back and forth one or two times.) Newsprint is highly acidic and deteriorates quickly, while most books take a little longer to decay. Many large academic and public libraries are facing serious problems because so many of their books are brittle; small libraries, too, must deal with books that will essentially self-destruct. Whenever possible, it is well worth buying materials on non-acidic paper! Several options for dealing with brittle materials may be worth considering.
- You may decide to ignore the material until it becomes unusable (if the item is not valuable or is easily replaced) or to discard the item and not replace it (if it is unlikely to be used).
- You could investigate buying a reprint edition on alkaline (non-acidic) paper (the least expensive option for materials likely to be used often).
- If the original item is not as valuable as the information it contains you might consider converting it to microform or electronic format, or make a photocopy on alkaline paper. Commercial firms can make a bound photocopy of materials. Keep in mind that these options may result in some damage to the original during the duplication process.
- Some irreplaceable materials might be enclosed in alkaline containers available from binderies to slow down deterioration, but these containers do not stop the deterioration process. If an item must be kept and you need to prevent further deterioration, you will probably need to have the book deacidified by a professional, an expensive process. (Evans, p. 471-475)
There are many ways that libraries can minimize damage caused by preservation problems. Some possible methods for handling these include binding materials, handling materials carefully, and repairing materials.
Binding and Rebinding
Your collection will determine how often you encounter the issues of binding and rebinding. If you regularly discard older journals, you may not need to bind anything in your collection. Rebinding is probably an issue if you have many books with damaged covers (especially paperbacks) that you cannot replace, either because new copies are not available or because it is cheaper to rebind. A reliable commercial binder may also offer repair services, which is a plus if you are not able or willing to attempt repairs yourself. There is a good listing of binderies at Yahoo!; there are also a number of binderies in Phoenix and Tucson. Check your local directory under “Binderies” or “Bookbinding” for more options.
Some basic guidelines for handling books can help reduce the number of damaged books you encounter. These suggestions should be familiar to both the library staff and customers. Avoid pulling on a book’s cover or shoving books across dusty surfaces. Do not pack books so tightly on shelves that their bindings become warped or their covers become torn by people trying to pull them off the shelf. On the other hand, books should sit upright on shelves, not leaning or bent to one side.
Non-print materials also require special care. Microforms should be handled by the edges, since fingerprints can obscure the images, and microfilm and microfiche readers should be cleaned regularly to prevent scratching. Care should be taken to handle compact discs and CD-ROMs by the edges and magnetic media (such as computer discs) should not be placed near strong magnetic fields. (Harvey, p. 99)
When you are trying to decide whether to repair a damaged book, consider the resources needed to repair it (time, money, supplies and expertise) versus the item’s value to the collection. If you decide to treat the book, you must choose from a spectrum of options that ranges from simple, expedient repair in the library to full conservation treatment by an expert. If the item is valuable or irreplaceable, be very wary of applying any technique that could further harm the book; on the other hand, if the item is easily replaced or likely to drop off in use, it may be less important to use “conservationally sound” techniques. You may have to aim for a balance between what is best for the book and what is possible given your resources. (Lavender, p. vii-viii)
The best way to learn about book repair is to take a class or workshop so that you can practice the necessary skills with the aid of an expert. If that is not possible, there are many good, detailed books and Web sites available. For a basic training guide, try A Simple Book Repair Manual from Dartmouth College. If you want to try creating a new photocopied book, some advice can be found at Bookbinding, A Tutorial. The following library supply companies are among those that stock book repair supplies: Gaylord, Kapco Library Products, and Vernon Library Supplies.
Evans, G. E., & Saponaro, M. Z. (2005). Developing library and information center collections (5th ed.). Englewood, CO: Libraries Unlimited
Lavender, K., & Stockton, S. (1992). Book repair: A how-to-do-it manual for librarians. New York: Neal-Schuman Publishers, Inc.