Preservation and Conservation of Information Resources
Babalola, Yemisi T.
Archives and Archival Materials
Archives are collections of records that are preserved permanently because of their enduring
cultural, historical, administrative, financial, legal or research value. Archives can also refer to
the special institutions where archival materials are stored. Every country has a national archive
where documentary heritage of each nation are kept. Archival materials are usually primary
source documents that individuals, families, communities, businesses and governmental
organizations have accumulated over the years as evidence of past decisions, events or
transactions. They may include letters, diaries, annual reports, legal documents, correspondences,
manuscripts, books, photographs, paintings, statues, artifacts, drawings, maps, newspapers,
pamphlets, plates, magazines, manuscripts, letters, microfilms, audio recordings, audiovisual
materials, magnetic tape diskettes or CD-ROMs. Archives are good sources of primary
information and valuable resources for research.
Library materials on the other hand are the print and non-print materials information resources
that have been selected and organized for easy retrieval and use by specific groups of users.
Unlike archival materials that are usually not in current use, library collections are meant for
current use and may be subject to wear and tear from intensive use. However, both library and
archival collections need to be managed so they can continue to serve their reference and
evidential functions. Besides, the financial and human resources invested in managing library
materials demand that such materials be preserved in the best condition for as long as possible.
Thus, preservation and conservation critical functions in library and archive management.
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Preservation of library and archival materials refers to all managerial activities, policies and
procedures that prevent or slow down the deterioration of materials and make them available for
use, either in their original physical form or in some other formats. Preservation is a preventive
measure that must be carried out routinely and integrated into every aspect of library operations.
Conservation on the other hand, refers to application of chemical and non-chemical procedures
to restore damaged library or archival materials to their original or near-original condition and
prolong their existence. It is the deliberate alteration of the chemical and or physical aspects of
materials in order to prolong their existence. Binding, sewing of book pages, stain removal and
leaf casting are all parts of conservation activities. Conservation measures are curative and must
be carried out by professional curators or on their advice only.
Differences between Archival and Library Materials
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Library Materials
Library materials are selected as single items
Archival Materials
Archival materials are appraised in
aggregates or groups
They are usually published materials
They are unpublished materials
Materials are described individually
Materials are described in aggregates
Materials are not necessarily unique; they Materials are usually original, unique and
can be easily replaced
sometimes irreplaceable
Materials are accessed from open stacks
Materials are accessed from closed stacks
Materials are described with card catalogues, Materials are described with inventories and
OPACs
guides
Arrangement is by provenance (ownership) Arrangement is by subject classification
and original order (Date of creation/ receipt)
Materials are loaned out to users
Materials are not loaned out to users
Library materials are selected and acquired Archival materials usually accumulate as a
with specific users in mind
result of business/ administrative activities of
individuals or organizations
A person who manages a library is called a A person who manages an archive is an
librarian
archivist
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Why Do Materials Deteriorate?
All library and archive materials are subject to deterioration over time. Often times, the natural
composition of the information materials themselves may predispose them to early deterioration
however, there are various environmental factors that may contribute to the deterioration of
documentary materials. They may be broadly categorized as chemical, physical, biological and
human agents of deterioration.
Chemical Agents
1. Acids- this is the major cause of internal deterioration of paper-based
materials which constitute the larger portion of library and archival
collections. The sources of acid in library materials include:
i.
Lignin that is contained in wood pulp. Lignin and other complex organic
compounds break down into acid components and cause paper to
deteriorate later.
ii.
Sizing agents such as rosin, gelating, starches and aluminium sulphate
added to paper during manufacture to reduce absorption of writing and
printing ink.
iii.
Bleaching agents used to produce white paper leave residue of acid in
paper.
iv.
Writing and printing inks have high acid content. Iron gall ink that was
used in the 17th and 18th century was highly acidic, burning into paper
and contemporary inks such as biro tend to fade over time and can lead to
loss of vital information.
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v.
Adhesives like glue, vegetable pastes, wax, masking or cellophane tapes
also contain amounts of acid.
vi.
The chemicals used to process photographs which can contain pollutants
and acids that can be hazardous to the photographs themselves and to
other materials in their vicinity.
2. Dust, gases and particulate matters- these include industrial gases, dust, car
exhaust, gaseous pollutants like sulphur oxide, nitrogen dioxide, hydrogen
sulphide and dust pollutants that come from the materials themselves,
especially those made with poor quality materials such as newspapers. Dust
particles have abrasive effects and can encourage mould growth on damp
materials. Audiovisual documents are extremely sensitive to dust leading to
poor signals or total signal breakdown.
Physical agents
1. Light- this is the part of the spectrum of electromagnetic waves that is visible
to human eyes. Most paper items are susceptible to damage from ultraviolet
(UV) light. UV radiation, which is emitted by the sun and fluorescent bulbs, is
particularly damaging to paper items because it causes photochemical
deterioration.
Exposing
paper-based
materials
such
as
watercolors,
manuscripts, newsprint and non-print media to intense visible light, causes
fading and/or yellowing.
2. Temperature and Relative humidity -temperature is the level of hotness or
coldness of a substance, body or environment while relative humidity is the
the amounts of water vapour in a given volume of air at a given temperature
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expressed as a percentage of the maximum quantity of water vapour, which
this same volume can contain at the same temperature. High temperature or
low relative humidity make the air dry, cause materials to become brittle and
speed up chemical actions in materials. On the other hand, high relative
humidity or low temperature causes materials to absorb moisture from the
atmosphere and become swollen and warped. This condition also promotes
mould growth however, fluctuations in temperature and relative humidity are
more damaging to materials because they cause them to expand and contract,
thereby weakening the materials physically.
3. Fire - can lead to total loss of library materials while the materials that are not
completely burnt may be discolored by soot and smoke and embrittled by
exposure to intense heat. Fire disaster often ends up as water disaster as water
is used to extinguish fire.
4. Water- Water causes materials to soften and stick together. It also causes ink
to run such that materials become unreadable. The source of water damage
may be traced to leaking pipes, leaking roofs, flooded rivers, hurricane or fire
fighting. Water damage can lead to further damage by mould if the materials
are not thoroughly dried. Water causes gelatinization of parchment rolls.
5. Disasters- Disasters are unexpected events that endanger lives and properties.
Disasters can be natural or artificial. Natural hazards such as earthquakes,
floods, landslides, drought, tropical cyclones and associated storm surges,
tsunami and volcanic eruptions have led to loss of human lives and destruction
of library buildings and collections. Artificial disasters may be caused by
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people's carelessness, poor maintenance culture or deliberate act of vandalism.
For example, artificial earthquakes may be caused by careless handling or by
the collapse of a roof or shelf and artificial flooding may result from leaking
roof or faulty pipes.
Biological agents
1. Mould and Mildew- these fungi that grow as masses of branching threads.
The two are similar in structure but distinct. The spores of mould or mildew
are always present in the air and on objects. Fungi don’t produce their own
food rather; they absorb nutrients from dead or living organic matter by
excreting digestive enzymes on them. Mould and mildew soften and weaken
books, making them difficult to handle. They also stain books and paper
irreversibly. People with allergies, asthma or other respiratory problems can
have serious reactions to their spores.
2. Insects and Rodents - insects such as cockroaches, termites, silverfish,
booklice, spiders, bookworms, beetles etc. and rodents- rat, rabbits, squirrel,
mice etc. are attracted by the cellulose of paper, the proteins and
carbohydrates of gelatin sizing, glue, paste, leather and other organic
substances. They eat through the materials, leaving holes and stains in them.
Their activities are encouraged by darkness, absence of ventilation, high
temperature and relative humidity..
Human Agents
1. Mishandling of materials- poor handling of documents while they are being
used, moved, photocopied, scanned or photographed often result in
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mechanical deterioration of library materials. Papers that have been folded or
rolled for long periods often become dry and brittle; and flattening may lead
to permanent damage.
2. Theft and Vandalism- theft of library material is a deliberate or intentional
removal of any library material from the premises of a library facility without
permission to do so while mutilation or vandalism implies malicious tearing,
squeezing, marking or defacing of library materials. These vices may lead to
total or partial loss of documents.
Preservation Practices
In order to ensure continued access to information materials, both staff and users of libraries and
archive must adopt good housekeeping practices that can prevent or delay deterioration of the
materials. This section highlights some of the house keeping practices that can help protect
library materials from agents of deterioration:
Light
 Ultraviolet screening film or curtains must be used to cover windows from sunlight
 UV filter, a material used to filter the ultraviolet rays out of visible light should be fitted
 on artificial light
 Use of paint or ceiling tiles that contain white pigment titanium dioxide which can
absorb UV radiation
 When not in use or display, materials should be stored in boxes.
Dust and other Pollutants
 Suitable vacuum cleaners should be used to remove dust from carpets, floors
 The surface of books, and shelves should be wiped with damp cloth.
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 Air conditioners with filters must be provided
Theft, Mishandling & Mutilation
 Library staff and users should receive regular training in handling of different materials
and equipment.
 The staff and patrons must ensure their hands are clean and dry or wear hand gloves
when handling materials like rare documents, film negatives and photographs.
 Materials must not be used while eating.
 Bound volumes should not be pressed hard for photocopying as this may damage
binding.
 Books should not lean at an angle on the shelf.
 Books should not be pulled at the top of its spine when removing them.
 Oversized books should be shelved separately.
 Provide a sound security system
Mould and Mildew
 Books and other documents should not be shelved directly against the wall in order to
avoid moisture developing along the walls.
 The storage area should be well ventilated and Materials must not be packed too closely
to allow air to circulation among them.
 Books should not be kept on the floor or covered with polythene for too long
 Quarantine affected items if a mould outbreak is detected and isolate and destroy all
wrapping material.
 Inspect collection regularly to detect infestation early before it becomes widespread.
Temperature & Relative Humidity:
 The temperature and relative humidity of archival and library buildings should be
monitored regularly with instruments like thermohydrograph, data logger, hygrometer or
humidity indicators.
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 There must be good ventilation in the storage area. The use of air conditioner is very
important.
 Do not pack materials too tightly into shelves or boxes so hot air does not build up and
raise temperature or humidity level.
Fire
 Smoking in the library or its premises must be prohibited.
 Storage/ use of explosive chemicals by library staff and users must be prohibited.
 The library should be built with fire resistant building materials to delay the spread of
fire.
 Install automatic fire/ smokes detection system
 Provide fire extinguishers in the library.
 Materials that are not yet shelved should be stored in fire resistant boxes and cabinets as
protection against fire and soot.
 All electrical faults must be fix promptly
Water:
 Water pipes and sinks should be inspected and maintained regularly.
 Water detection alarm systems should be installed in the storage rooms
 Shelves must be at least four inches off the floor.
 Collections stored temporarily must never be placed directly on the floor, but always on a
pallet.
 Collections must be stored at a safe distance from plumbing, electrical and mechanical
installations like water pipes, radiators, air conditioning, kitchens or laboratories.
Insects and Rodents
 Examine newly acquired material for signs of infestation
 Isolate, bag and remove infested materials
 Identify the pest causing the problem.
 Fill cracks and crevices in walls and floors
 Vacuum the building regularly to remove insects and their eggs
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 Ensure good ventilation in the building
 Clear bushes around the building.
 Ensure that pests are not carried into the building in fresh flowers, vegetation and potted
plants
 Do not allow eating and drinking in the library facility.
 Bag, seal, label and freeze infested materials.
 Ensure good housekeeping practices activities such as garbage removal and cleaning of
floors
Acids
Paper acidity can be prevented by making sure that alkaline paper or acid-free paper are used in
documenting information.
Library Weeding: Why and How?
Library weeding or deselection is the planned and systematic removal of materials from a
library's collection. Library weeding is an important activity that must be carried out library
materials that have outlive their usefulness. Weeding not only saves library space, it also saves
the time of the users and makes a collection clean and attractive. It helps to keep library
collection current, accessible, and tailored to users’ needs. However, care should be taken so as
not to weed out useful materials from a collection. The collection development policy should
state clearly the criteria for weeding and should be consulted in carrying out this exercise.
Guidelines for Weeding
There are various guidelines for weeding library materials. Among the most popular is the
CREW (Continuous Review, Evaluation, and Weeding) method presented by Joseph P. Segal
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(1980) in his book, Evaluating and Weeding Collections in Medium and Small-Sized Public
Libraries: The CREW Method. The model suggests six general criteria known as MUSTIE for
removing materials from a library's collection:
1. Misleading- information is obsolete or factually inaccurate or presents racial, cultural or
sexual bias.
2. Ugly- old, brittle, tattered, stained or scratched materials that are damaged beyond repair
or if their formats cannot be supported by current technology
3. Superseded- outdated information such as old editions of books or contents that were
once 'hot topics' but are no longer relevant
4. Trivial- information content of no discernible literary or scientific merit or is of poor
quality or poor writing style, below readers level.
5. Irrelevant- they are unused within 3-5 years because they are no longer relevant to the
local demographics or the curricula. e.g. periodicals that are not included in standard
indexes
6. Elsewhere--the material is easily obtainable from another library or in another format.
Bindery and Binding
The bindery is one of the technical sections of the library where activities that preserve
library materials and enhance their physical form are carried out. The bindery supports
the library by binding and repairing worn out books and journal article to make them easier
to use and extend their life span. The bindery also offers commercial services by binding
books, theses and dissertations for patrons at affordable prices.
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Revision Questions
1. Mention 5 differences between library and archives
2. What are the implications of not weeding a library's collection?
3. How you will prevent and remedy the damage done by rodents and insects to paper-based
materials?
4. What are the effects of these physical elements on library collection and how will you
protect your library from them?
i.
ii.
iii.
Sunlight
Temperature
Water
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