The shelves on which books and other materials are stored in a library are referred to as a

In a busy library, shelving and shelfwork is a never-ending and seemingly, thankless task. The arrangement of books in the library makes them accessible and usable by library patrons. If materials are misplaced or never reshelved, locating information would be impossible. It is recommended that all library materials be reshelved within twenty-four hours of their return to the library, yet many libraries fail to realize the importance of shelf work. Although shelvers may rarely come into contact with library patrons and are often the most junior people on staff, the quality, speed, and efficiency with which shelving is carried out will affect how patrons view the library and its services. Backlogs of unshelved materials cause delays in service because patrons must wait for unshelved items to be located. Shelving and shelfwork is critical to the efficiency and effectiveness of any library.

Terminology of bookshelves
Before discussing shelving arrangements, it is important to be clear on terminology used to describe shelves and shelving in libraries. There are four components to bookshelves:

1. Shelf – A flat piece of wood or metal that is placed horizontally between two uprights to hold books. Shelves are hung in a series of slots running the length of each side of the upright. This permits shelves to be easily adjusted for materials of varying heights. A 3ft. shelf length is the standard. Depths of 8, 9, 10, and 12 inches are available. However, a 9 inch depth is considered the standard.


2. Section (also called a Bay) – A vertical series of shelves, between two uprights. A section is 3 ½, 5 ½, or 7 ½ feet high. The section is the basic unit of shelving and may be
   a. Double-faced – shelves are hung on both sides
   b. Single-faced – shelves are hung on one side only and are usually placed against a wall


3. Range – A number of sections lined up end to end. Ranges are aligned parallel to each other. Sections of freestanding shelves are usually bolted together and made more aesthetically pleasing by installing end panels. As well a range will be capped with a top, referred to as a canopy top. The canopy top adds stability, protects books on the top shelf from getting dusty, and gives a finished appearance to the range.


4. Stacks – All of the ranges within the library are collectively referred to as “the stacks”. The aisle width between ranges should be a minimum of 3 feet. Information about access for people with disabilities is available from the National Library of Canada.

Different types of shelving
In addition to the standard shelving illustrated above, there are a large variety of display and special purpose shelving available for:

• audiovisual materials
• periodicals and paperbacks
• special displays (e.g. new books)

As well, special types of storage shelving has been developed to help libraries rearrange their collections to increase capacity. Compact storage systems can house more books than traditional shelving in the same amount of floor space because most aisles are eliminated. There are two kinds of compact shelving:

1. Compact mobile shelving
When an aisle is required, the stacks are moved to one side or the other to open-up an aisle. The ranges are mounted on metal rails and can be moved by: pushing, use of a mechanical crank, or use of an electric motor. When an aisle has been opened, there is no aisle access available for the neighbouring ranges. Built-in safety devices ensure that an aisle cannot close with a patron standing in it. Patrons and shelvers may have to line up while waiting for unavailable ranges. Browsing time may be limited if others are waiting. This type of shelving is usually used for infrequently used material or for items that can be retrieved without browsing (e.g. outdated book collections or old runs of bound periodicals). Because of the weight of compact movable shelving is heavier than standard shelving, it must be installed on the ground floor or in a specially built facility.

2. Sliding drawer system
This type of shelving is a fixed framework of individual shelves can be pulled out into the aisle. It requires more aisle room than standard or compact shelving.

Open and closed stacks
Library collections can be open stacks or closed stacks. There are reasons to have both in a library and implications for library staffing and shelf work.

1. Open stack collection
Open stack collections give patrons complete access to the materials on the shelves. Patrons may browse and choose their own materials. The result of open access is more reshelving and maintenance to keep the collection in call number order. There are extra problems with security. Libraries try to discourage patrons from reshelving their materials because untrained individuals may misshelve materials and as a result materials become lost. Signs are typically posted encouraging patrons to put material they have used onto specially designated carts, tables, or shelves. This facilitates the job of collecting, sorting, and reshelving materials for library staff. The level of maintenance required in an open stacks collection is justified by a major increase in accessibility for the patron.

2. Closed stack collection
Any collection that is not open to the general public or only on a selective basis is a closed stack collection. Stacks are usually closed to protect rare or valuable material or control high-demand materials. In libraries with closed stacks, materials are “paged”, i.e. the item is retrieved by a library staff member and brought to the patron. The patron requests the material by writing the call number on a “call slip” that is given to a staff member at the circulation desk. The library staff member, or page, is sent to select the requested book from the closed stacks and carries it or sends it by conveyor or booklift to the circulation desk where it is given to the user.

Closed stack collections are prevalent in universities, special libraries, and archival collections. Since the collection is accessible only to library staff, it is generally in better call number order and requires less maintenance. Also, the stacks can have narrower aisles than open stacks, so the collection may require less floor space.

Libraries with open stacks may keep certain materials in closed stacks because they are in high demand, valuable, or may be stolen. Some materials are kept in closed separate stacks because of their physical shape (e.g. maps or newspapers). As well, if a collection is very large and the library has fixed stack space, little used materials are often kept in a closed stack storage area.

Shelving arrangements
The arrangement of books on the shelves make them accessible to patrons and library staff. Unless you are starting or completely revising a library collection, the arrangement of materials in the stacks is already established.

In all types of libraries, nonfiction is usually arranged according to classification systems (Dewey Decimal or Library of Congress). These systems group material by subject and make it possible to browse the shelves.

In public libraries, fiction is arranged in one of three ways:
* Alphabetical order according to the author’s last name
* By type or genre (e.g. science fiction, mystery, romance)
* By audience (e.g. children, young adult, adult)

Academic libraries classify fiction as “literature”. Literature is arranged by call number (usually Library of Congress) so that an author’s works are shelved in the same area with the criticism of these works.

Most libraries have reference material shelved in a separate area from the regular collection. Reference materials will include such things as dictionaries, atlases, and handbooks that are consulted on a regular basis.

Other materials that are often kept in separate areas include:
* audiovisual materials
* biographies
* foreign language materials
* government publications
* large print books
* microformats – eg. Microfilm or fiche
* new books
* newspapers
* paperback fiction
* periodicals
* rare books

Shelving these types of materials in separate areas facilitates browsing. As well, the nature of the material may require special cases or shelving. However, separate areas makes shelving, retrieval, and browsing more complicated. Signage and library maps are helpful tools for explaining library arrangements.

Materials are arranged in the stacks using a block arrangement. The typical pattern of shelving is from left to right, from the top shelf down, section by section, and range by range.Call numbers and shelving
Library materials are assigned to their places on the shelves through the use of call numbers. These are found on the spine label. Call numbers arrange materials by subject based on classification systems. In addition, the call number divides subject classification by author. In North American libraries, the two most common systems are Library of Congress and Dewey Decimal.

Dewey decimal classification
In public and school libraries nonfiction books are usually shelved according to the Dewey Decimal Classification (DDC) system. These call numbers consist of whole numbers and decimals (e.g. 629.13, 629.5. 629.9). Typically a DDC is not sufficient to identify a work for all library purposes. A book number, also called an author number or Cutter, is added to the classification number to create a unique call number for each item in the library. The call number is composed of a classification number and an author number (e.g. 629.13 A253).

The book number is used to create a unique call number. The simplest form, used by small school and public libraries, is one to three letters from the author’s last name. Instead of an author number, many libraries use Cutter numbers, named after their inventor Charles Ammi Cutter. The author number is derived by combining the initial letter or letter(s) of the author’s last name with numbers from a numerical table designed to ensure an alphabetical arrangement of names. The Cutter number is a decimal.

Components of DDC call number with a cutter number
Example:

629.13
A253

629 = The first part of the classification number is a whole number and is filed numerically.
.13 = The next part of the classification number is read and filed as a decimal
A253 = The third line is filed by the letter and then by the number. However, the number is read as a decimal.

A sample shelving arrangement for a DDC call number using a simple author would appear as follows:

For example, four books with the following call numbers:

641.5 Con
641.564 Cot
641.145 Cor
641.49 Con

Would have a correct sequence of:

641.145 Cor
641.49 Con
641.5 Con
641.564 Cot

Remember the latter part of the classification number is a decimal. Number “49” comes after “5”, yet “.49” is smaller than “5”. Similarly, “.5” is smaller than “.564”.

A sample shelving arrangement for a DDC call number using a Cutter number would appear as follows:

Four books have DDC call numbers with Cutter numbers as follows:
697.042 D30
697.001 D565
697 D345
697.042 D34

The correct sequence would be:
697 D345
697.001 D565
697.042 D30
697.042 D34

In school and public libraries, fiction books are often simply shelved alphabetically by the author’s last name or simply by the author number or the cutter number. The classification number is usually used only with non-fiction.

Library of Congress
Most academic and special libraries shelve books according to the Library of Congress (LC) classification system. These call numbers are based upon groups of letters and numbers. The letter number combinations represent subjects.Components of the LC call number
LB The first unit consists of letters and is shelved alphabetically
2395 The next unit consists of whole numbers and is shelved numerically
.C65 The third line is shelved by the letter and then by the number. However, the number is read as a decimal
1991 The final line is the date of publication and should be filed chronologically.

A sample shelving arrangement for LC Call numbers would be:

Juv Juvenile Juv C244
Ref Reference Collection Ref Q 175 .E3
Oversz Oversize Collection Oversz Q 175 .E3

Shelfwork
Shelfwork is the physical maintenance of the stacks and involves: sorting, shelving, shifting, and shelf-reading.

1. Sorting
Materials to be shelved come from a number of sources:
* returned material
* new acquisitions
* books used by patrons in the library and left on tables or special shelves

Before materials can be shelved, they need to be broken down into workable units according to shelf location and call number. Sorting prepares materials for efficient and quick reshelving. Sorting is usually done on book trucks or on special shelves.

2. Shelving
Shelvers move book trucks of sorted library materials to the appropriate location to begin shelving. As the books are shelved, the shelvers should be looking for misshelved materials and routing them to the sorting area, or reshelving them properly. Shelves should be straightened by aligning all spines even with the edge of the shelf. This makes it easier for patrons to see titles and remove them from the shelves. At the same time, volumes should be shifted to the left side of the shelf. A book support (a wire fixture hanging from the shelf above) or bookend should be used to draw the books closely together to prevent lean.

Books should not be tightened too much with the book support or bookend. If books are too tightly packed, patrons will have difficulty removing books and may damage book spines. Also, if they attempt to reshelve a book they will push several books to the back of the shelf.

If books are too loosely packed, the patron will push some of the books to the back of the shelf. Eventually, they fall in behind the shelf and are not easily found. Loosely packed books may fall off the front of the shelf and hurt someone. Books will sustain damage if they are leaning at sharp angles.

3. Shifting
Shifting is the process of moving sections of books. A shift may be necessary because:
* a collection is being rearranged
* differential growth in the collection
* portions of the collection are being removed
* new shelving has been added
* a new facility has been built

To minimize disruptions to patrons, shifts should be scheduled during periods of low collection use (e.g. over holidays or between semesters).

Free space can be obtained by:
* leaving top or bottom shelves empty
* leaving space at the end of each major break in classification
* leaving space at the end of each range

Each shelf should be left roughly two thirds full. This gives enough room to shelve new books and returned books without overcrowding.

Remove books from the shelves by grasping them in the middle rather than tugging at the headcap. Adjacent books can be pushed slightly towards the back of the shelf so enough of the book can be exposed for grasping.

Book trucks are usually used for transporting materials. They should be loaded in the following manner to prevent nonsequential transfer to the new location and to keep the truck from tipping.

Load carts with the spines facing outwards, not up, to prevent spine damage.

Materials should be carefully placed in order in their new location. Range numbers and directional signs will need to be modified.

4. Shelf reading
Following a shift and on a regular schedule throughout the year, the collection should be shelf-read. Shelf-reading is the process of checking the shelves to make sure that each item is in its proper place. Books get out of order because of staff and patron errors. To keep the collection in order, each shelver is usually assigned a particular section of the stacks that they are responsible for reading on a regular basis (e.g. daily, weekly, or monthly).

The library literature recommends shelf-reading at least once a week. In most libraries, there is simply not enough time, or staff, to shelf-read the entire collection once a week. Heavily used areas are shelf-read daily and other areas read less frequently.

As the shelves are read, any materials on crowded shelves should be shifted. Shelf-reading usually turns up lost or long overdue items that were incorrectly shelved. Shelf-reading is psychologically and physically challenging. Because it is boring, eye-straining, and stressful on the back, each shelf-reading session should be no more than 1 to 2 hours with a break every 30-45 minutes.

Additional references
Bright, Franklyn F. Planning for a movable compact shelving system. Chicago : American Library Association, 1991.

Hubbard, William J. Stack management: a practical guide to shelving and maintaining library collections. Chicago : American Library Association, 1981.

Weihs, Jean. Integrated library: encouraging access to multimedia materials. Phoenix : Oryx Press, 1991