What are the proper storage practices for specific types of paper collections? How do you know whether your current storage is acceptable? In this section, you will review commonly recommended storage practices for paper-based collections and use this knowledge to evaluate your own storage methods.
You will be looking for poor storage practices that are common in collections (e.g., rubber bands holding covers together, poorly supported books, overstuffed file folders, acidic inserts in books or files). Although this examination may locate individual objects that need repair or other treatment, its primary goal is to identify general needs and areas of the collection in need of remedial actions (e.g., boxing, enclosing photographs, replacing manila folders with archival-quality folders and boxes, and photocopying news clippings).
If important individual objects requiring conservation treatment are identified during this process, a conservator can evaluate whether emergency care is indicated. See Conservation Treatment for more information on treatment and working with a conservator.
This review of collection storage needs is organized by type of material, since for the purposes of preservation it is usually best to store like materials together. It is sometimes necessary, however, to consider mixed collections as a whole.
The first step in safely storing bound volumes is to ensure adequate shelving. Shelving that is too shallow allows books to extend beyond the edges of the shelf, which exposes them to book trucks, backpacks, vacuums, and feet. If the shelving is not sufficiently strong, shelves can bow and the entire unit can become unstable. Finally, some shelving units contain chemicals and by-products that contribute to the deterioration of collections, or may have rough surfaces that can be abrasive. For information on selecting quality shelving for paper-based collections, consult NEDCC Preservation Leaflet 4.2 Storage Furniture: A Brief Review of Current Options.
To avoid damaging bindings, books need to be shelved upright and supported. Non-damaging bookends with smooth surfaces and broad edges prevent bindings from being abraded and leaves from being torn or creased. The non-knifing variety of bookend, which has a lip, is preferred to the knifing variety, which allows books to be jammed onto its sharp edge. A brick covered with book cloth (fastened with PVA) can be a good book support. Another alternative is to cover the sharp part of a knifing bookend with a piece of acid-free foam, covered with book cloth.
If books are too tall to fit appropriately on the shelf, they may be moved or shelves rearranged so that the books fit on the shelves standing upright. If moving or rearranging is not possible, store volumes with the spine down (storing a book with the spine up may cause the text to pull out of the binding due to its weight). As much as can be managed, shelve books by size since small volumes cannot adequately support larger ones. House very large or heavy volumes lying flat, because upright storage can result in heavy books pulling away from their bindings. When books are stored horizontally, stacks should only be 2-3 volumes high to make retrieval less intrusive. As for upright books, shelves should be wide enough to support oversize books completely so that they do not protrude into the aisles. Bindings with special value should be boxed to prevent abrasion to the bindings when stored flat. Take care to ensure that call number flags or titles are visible so that the books can be identified on the shelf.
Boxes constructed of preservation-quality materials can be custom made to fit a book's measurements. They provide support for the volume and protection from dirt, dust, light, and mechanical damage. Volumes with artifactual value, where the fragile bindings are to be retained in their present condition, should be boxed. Volumes that have low value or are rarely used and do not warrant treatment or repair of the binding may also be boxed.
Boxes can be made in-house or contracted out. Drop-spine boxes provide the most protection. Phase boxes are not as rigid or impervious to light or dust, but they are an acceptable cost-efficient alternative. Ready-made rare book boxes can be purchased from conservation suppliers. If they are to provide proper protection, boxes must fit the books closely and the weight of the board or card stock must be appropriate for the size of the books. Many vendors make both drop-spine and phase boxes. Deteriorated books of great value should have custom-made drop-spine boxes that fit the book exactly.
Infrequently used deteriorated books can be wrapped in buffered paper or fitted with polyester book jackets (see NEDCC Preservation Leaflet Polyester Film Book Jacket for instructions). Both of these strategies will prevent dispersion of the "dust" from red rot and provide some protection from dust and abrasion. These strategies are cheaper than boxing, but they offer less protection. Among the disadvantages: a polyester book jacket does not cover the book completely; the paper and polyester film do not provide as much support as box board; and it can be difficult to replace a paper wrapping properly once it is removed for use.
If detached covers must be tied onto books as a temporary protection, ties should be undyed cotton or linen tape or undyed polyester ribbon. Any knots should be at the top or fore edge of the text block to prevent damage from pressure against other books. Never hold damaged bindings together with rubber bands; the rubber bands themselves will deteriorate and cause further damage.
Pamphlets and small booklets can be stored in specially made enclosures, in folders and boxes, or in hanging folders in file cabinets. Pamphlets of the same cover size can be stored in drop-spine or phase boxes. Pamphlets that differ in size may be stored according to guidelines given for manuscripts and documents. Pamphlets more than about a quarter-inch thick should be stored spine down in individual folders. Pamphlets of very different size should not be stored in the same folder.
If individual pamphlets must be shelved between books, they should be individually boxed. Groups of pamphlets shelved between books can be boxed together if the guidelines above are followed. If pamphlet binders are used, they must be of preservation quality throughout, and they should never be glued directly to pamphlets. Where stitching is used to join pamphlet and binder, it should be done through the fold or, where possible, in original fastener holes.
Documents should be stored in acid-free, lignin-free, buffered file folders, with a maximum of about 15 sheets per folder. The folders should then be placed in archival-quality document storage boxes as close to the size of the folders as possible. All folders in each box should be the same size. Boxes should be full enough to prevent slumping of the contents; partially full boxes can be filled with spacer boards available from conservation suppliers. Overstuffed boxes can cause damage when sheets are being removed or refiled. See Preservation-Quality Enclosures for general information on enclosures.
An alternative to boxed storage is a standard baked enamel file cabinet equipped with hanging racks and hanging folders. Archival-quality hanging folders are available, but the conventional kind are acceptable as long as the folders within them are acid-free, lignin-free, and buffered.
Store objects of the same size and category together whenever possible. Archivists habitually organize collections by subject group, but objects of differing bulk and weight can cause damage from uneven pressures in a drawer or box. It is not advisable to store single sheets in the same box with books or pamphlets unless there are separate enclosures and supports for each category of material. Generally speaking, heavy or bulky objects should be stored separately from lighter objects.
Parchment and vellum are highly susceptible to damage from fluctuations in relative humidity and thus require stringent humidity controls. Such documents should be enclosed for additional protection. Suitable enclosures include encapsulation in polyester, folders, matting and framing, boxing, or a combination of these techniques.
Ephemera may have raised surfaces or three-dimensional decoration. Items should be grouped by size and type (e.g., postcards, printed material, documents), enclosed to protect them from chemical migration and mechanical damage, and stored to support the structure of the artifact (encapsulated, boxed, stored flat or in hanging files). Some vendors of archival supplies offer custom-size storage boxes and sleeves for common ephemera such as postcards and stereo views, or they can produce custom-size boxes in large quantities to meet special needs.
Because groundwood papers were commercially produced after about 1840, newsprint after that date is likely to be highly acidic. Long-term preservation of this paper is difficult at best. It is possible to treat newsprint by deacidification to retard its deterioration, but this treatment is usually economically impractical. Once paper has already turned yellow and brittle, deacidification will not make the paper white and flexible again. Reformatting through microfilming or digitization is usually the preferred preservation option for bound newspaper collections or large collections of clipping scrapbooks.
Most news clippings are important because of their information, not for the value of the clippings themselves. For this reason, photocopying, scanning, or microfilming is considered the most practical preservation options. All photocopying should be done on archival-quality paper; originals can then be deaccessioned at the discretion of the librarian or curator. News clippings with photographs that do not photocopy well may be physically separated from other papers in a folder by placing them inside an enclosure made of polyester. News clippings to be retained in their original form should be deacidified and stored in buffered enclosures.
Prints, maps, broadsides, and other oversize objects are best stored flat in map drawers or in large covered boxes of preservation quality available from conservation suppliers. It is acceptable to store documents legal-size or smaller in upright archival boxes, but anything larger than 15 by 9 inches should be stored flat. Sheets smaller than 30 by 40 inches will fit into archival boxes, which come in various sizes and are cheaper than map cases. Objects should be protected in neutral or buffered folders cut to fit the size of the drawer or box, since smaller folders tend to shift position as the drawers open and close and get jammed at the back of the drawers. Several objects may be placed in a folder. Items of special value should be interleaved with buffered or neutral tissue paper.
It was traditionally recommended that some items (such as blueprints) should not be stored in alkaline-buffered folders because they are sensitive to alkaline materials and might be damaged by contact with the folders. Recent research, however, has indicated that as long as the relative humidity in the storage area is kept moderate (between 30 percent and 55 percent), alkaline folders should not cause damage.
If map drawers or boxes are not available, or if objects are too large to fit in map drawers, oversize objects can be rolled on tubes, as long as the paper is not too brittle to withstand unrolling. If rolling the object on a tube, use a tube longer than the rolled object and at least four inches in diameter (larger diameters are preferred). If the tube is not archival quality, the object must be wrapped in neutral or buffered paper. Carefully roll the object onto the tube, and wrap the assembly with neutral or buffered paper to protect it from abrasion. This assembly can then be stored inside a larger tube for added protection. Tubes should be stored horizontally. Alternatively, oversize objects can be rolled within a polyester folder. See NEDCC Preservation Leaflet Storage Solutions for Oversized Paper Artifacts for instructions for making a rolled polyester folder.
Any prints, drawings, or other objects that have been matted or backed with acidic materials or wood should be removed from those mounts. They may be matted using preservation-quality materials and reframed in their original frames using museum-quality materials. These objects may also be safely stored flat (unframed, matted, or unmatted) in folders inside boxes or drawers, like oversize items.
Frames should not use eye screws or other protruding hardware for hanging, because they can cause damage to other frames or glazing. Protruding hardware should be replaced with D-rings on brackets, available from framers. Glazing should filter UV light and should never touch the artifact inside the frame. An additional layer of preservation-quality matboard should be used behind the board on which the object is mounted. The frame should be deep enough to accommodate all the layers, and it should be sealed so that it is as airtight as possible. See NEDCC Preservation Leaflets Matting and Framing for Art and Artifacts on Paper and How to Do Your Own Matting and Hinging for details on matting and framing.
Framed items should not be exhibited permanently. When not on exhibit, they should be stored vertically. Usually a padded frame rack is most practical for smaller institutions, while custom sliding storage racks (where metal grill panels are suspended from tracks) may be appropriate for institutions with larger collections of framed objects. Frame racks are available ready-made or can be constructed from non-damaging materials. Each compartment in a frame rack should be cushioned at the bottom, and foamboard should be used between framed items within the compartments to prevent abrasion. Revisit Session 3: Caring for Collections for more information on exhibiting collections.