Indispensable for the success of preservation efforts at the institutional level is the ability to tailor treatments to an array of problems. Research libraries with comprehensive preservation programs use a variety of approaches to carry out their responsibilities to maintain research resources for use.14 These approaches range from traditional methods of commercial binding to intricate treatments of rare materials to digitization. Some options treat collections on a macro level and require no item-specific intervention. Other options protect or restore texts one by one. Still others reformat endangered items, capturing only the information content. All preservation programs require complex decision making to choose the most effective approach to ensure continued availability of valuable scholarly information. Preservation options will vary widely in labor requirements and technical facilities, and hence cost. Maximizing benefits from investments entails difficult trade-offs.
From a cost-benefit standpoint, the single most effective preservation action is to store collections at properly controlled temperature and humidity. Temperature, relative humidity, light, air quality, and wide fluctuations in temperature and humidity have a direct and continuing impact on the longevity of research materials. Research has shown that storing print collections at 60 instead of 80 degrees Fahrenheit will extend their life by more than 300%; paper degrades about twice as fast at 50% relative humidity as at 25%.15 Improving environmental conditions will buy time, increase the life span of all materials in the collections, and extend the time available for preserving them.16
Although improving storage conditions will significantly lengthen the useful life of research materials in the aggregate, only labor-intensive treatment of texts one at a time can repair damage and ensure availability of the original work for use. Collections care efforts have traditionally focused on books and other paper-based materials. Many treatments are available to prolong the life of these materials—for example, putting low-use items into protective enclosures; repairing or rebinding high-use items; and conserving materials that are rare or otherwise have artifactual value. Timely minor repairs can ensure the continued safe use of most library materials. Such limited repairs retain the original bindings and minimize changes to the original formats of texts with artifactual value. Most importantly, not only are a significant number of damaged materials restored to usable condition in this way, the overall condition of the collections is gradually improved as well.17
Another strategy is to deacidify acidic books and other paper-based materials. Mass deacidification is an effective way to deal with acidic books that are in otherwise sound condition. The process neutralizes the acids in book papers and leaves an alkaline reserve against future acid attack. Deacidification can extend the useful life of paper by over 300%.18 This strategy allows retention of acidic but not yet deteriorated volumes in their original format. Although the goal of large-scale mass deacidification at low unit costs has proved elusive, selective deacidification is a standard component of preservation programs. It is a technology especially well suited for acidic books and documents that have scholarly value as artifacts and therefore must be preserved in original form.
In contrast to environmental control, conservation, and deacidification, reformatting does not treat the artifact but instead focuses on reproducing and saving the intellectual content of endangered items. Reformatting creates a permanent replacement of deteriorating monographs, journal volumes, and other paper-based documents. Libraries have used preservation microfilming to reformat at-risk materials since the 1930s. It is a mature technology that is governed by a detailed set of standards, but it is also an imperfect technology. Microfilming cannot affordably capture detailed, continuous-tone, or multicolored illustrations, and it complicates access, being machine-dependent. Reformatting has been the primary preservation strategy used to rescue brittle nineteenth- and early-twentieth-century texts. The most common option is to film the deteriorating volumes, but in some instances photocopying onto permanent, alkaline paper is used as an alternate approach.
Digitization is the newest technology that may hold promise for preservation reformatting of books, manuscripts, and other printed texts. "The conversion of textual, visual, and numeric information to electronic form—from preparation and conversion to presentation and archiving—encompasses a range of procedures and technologies with widely varying implications and costs," observe Dan Hazen, Jeffrey Horrell, and Jan Merrill-Oldham.19 There are many different ways of digitizing. In The Digitization of Primary Textual Sources, Peter Robinson lays out some of the complex choices that must be made—for example, whether to scan texts at one resolution or another, and whether to bitmap or key texts.20 Such decisions affect a scholar's use of and ability to manipulate texts and images. The benefits of networked access are a powerful driving force for digitization, but significant concerns remain: digital resources are dependent on complex technical systems that must be continually upgraded, and no standards exist for the archival permanence of such resources. These problems must be solved in order to preserve original digital works as well as to rely upon digitization as a preservation reformatting strategy. Libraries engaged in digitizing for preservation are operating, for the most part, pilot projects to gain experience and, as Suzanne Kellerman and Rebecca Wilson say, to "explore long-term possibilities for the future."21
Beyond these primary approaches, librarians have developed a range of other activities to keep endangered research collections accessible for teaching and scholarship. Some preservation strategies, such as improving storage conditions, may be invisible to scholars. Some, such as rebinding, will have more apparent results. And some, such as reformatting, will transform how a scholar uses texts; transference to electronic media, for example, may support new ways of teaching and new kinds of scholarship. It is important that scholars understand not only the causes and consequences of the deterioration of different information media, but also the choices involved in protecting and preserving research collections at risk. Scholars should participate in the debate about priorities for action.