Print Material Preservation and Conservation Techniques: In case of print material preservation, the following remedies can be taken-
a) Environmental Remedies: Poor qualities of building where books are stored and extreme climatic conditions create damage and decay of the library materials. The key environmental factors include temperature, relative humidity, pollutants, and light exposure. Books stored in cool, dry, dark areas generally have a much longer life span than those housed in hot, humid, brightly lighted areas. Constant or stabilized levels of temperature and humidity are less harmful than the fluctuating levels.
Maintenance of suitable environmental condition is the base on which all other preservation and conservation activities rest. Each material has its own unique temperature and humidity factor. Thermometers, Hygrometers, Humidity indicator strips, Hygrothermometer (for monitoring temperature and relative humidity) are generally used to monitor the environmental factor. Light meter and ultraviolet meter can be used to measure the exposure of light to the documents. The use of climate-controlled storage facility is the best way to maintain a suitable environment. Let us discuss these factors in more details-
i) Temperature: Lower temperature is good for a collection in a library. However, since books and other materials are often housed in areas with people, a compromise must be struck to accommodate human comfort. A reasonable temperature to accomplish both goals is 65-68˚F. However, if possible, film and photography collections should be kept in a segregated area at 55˚F.
ii) Humidity: Books and other materials take up and give off moisture, making themselves sensitive to relative humidity. Very high humidity encourages mold and insect growth. Low humidity causes materials to lose their flexibility. Fluctuations in relative humidity are more damaging than a constant humidity in the middle or low range. Generally, the relative humidity should be between 30-50% with as little variation as possible, however recommendations on specific levels to maintain vary depending on the type of material, i.e. paper-based, film, etc.
iii) Light: Exposure to light also has a significant effect on library materials. It is not only the light visible to humans that can cause damage, but also ultraviolet light and infrared radiation. Light is measured in lux or the amount of lumens/m2. The generally accepted level of illumination with sensitive materials is limited to 50 lux per day. Materials receiving more lux than recommended can be placed in dark storage periodically to prolong the original appearance of the object. Using ultraviolet filter on windows and light will also help.
iv) Pollutants: Particulate and gaseous pollutants, such as ozone, sulfur dioxide, oxides of nitrogen, soot, can cause dust, soiling, and causing irreversible molecular damage to materials. Pollutants are exceedingly small and not easily detectable or removable. The introduction of the “Heating, Ventilating, and Air Conditioning” (HVAC) filtration system in the building will be helpful defence against the pollutants.
b) Controlling Biological Agents: Pests, such as insects and vermin, eat and destroy paper and the adhesive that secures book bindings. Food and drink in libraries, archives, and museums can increase the attraction of pests. They are most common in cool, damp, dark, and undisturbed areas of libraries, archives, and museums
In general, if materials are stored in a clean, cool, and dry environment, and looked at and dusted occasionally, the risk of damage by insects is greatly reduced, and problems will be detected before a lot of damage is done. An Integrated Pest Management system is one way to control pests in libraries.
To kill the cockroach or black beetles, Gemmaxene or DDT powder may be used. These insects can also be repelled by camphor and naphthalene. Fumigation and naphthalene bricks are more effective to kill bookworms. To eliminate termites or white ants carbon bisulphide or carbon tetrachloride can be used. Solignum oil may also be used in stack rooms as a precaution. Boric acid and sodium floride and flour (12: 100) can be used against silver fish. Book lice, fish insects can be avoided by using ethylene, carbondioxide and formaldehyde vapours. A mixture of thymal crystal (100 gm), mercuric bichloride (4 gm), ether (200 cc) and benzene (400 cc) can be used to destroy the fungus layers.
c) Mass Deacidification: Acidic paper especially when exposed to light, air pollution, or high relative humidity, becomes yellow and brittle over time. Mass deacidification is a possible measure against the degradation of paper in old books. The purpose of deacidification is to neutralize acids and to deposit in paper a buffer that will protect the document from the formation of acid in future. During mass deacidification an alkaline agent is deposited in the paper to neutralize the existing acid and prevent further decay. The goal of the process is to increase the pH of acidic paper on a large scale. The deacidification may be aqueous and non acqueous in nature.
d) Remedies for Poor Qualities of Paper / Binding: Many reading materials that were published before 1950 were printed on very poor quality paper. Print materials in developing countries are often created using fragile, non-lasting paper product and ink. Creating and adopting a minimum standard of quality in terms of paper and ink, types of binding, etc is the only viable solution in this regard.
Library binding is the term used to describe the method of binding serials, and re-binding paperback or hardcover books, for use within libraries. Library binding increases the durability of books, as well as making the materials easier to use. It is a way to increase the life of the books and periodicals used in libraries. This is done by sewing the pages in place and by reinforcing the spine for each volume. The goal of library binding is long-term preservation.
e) Human Being as an Agent of Damaging Books: No type of material which circulates is safe from possible destruction. The damage to the books and other reading material is also caused by human beings due to its over-use, neglect, and such factors. The kind of book-return facilities provided and even the procedures used by the staff members responsible for processing and shelving materials also cause the deterioration of library materials. Books which are tossed around, dropped in a puddle or gnawed by the dog are lost to the collection. Therefore, proper care in handling the material should be ensured while the reading materials are in the hands of the users. The user awareness can do a lot in this regard. Shelvers can be taught to shelve materials properly, avoiding packing shelves too tightly or placing books with fore-edges down. When processing new materials, librarians should be careful about their use of tape or paper clips or other suppliers which might react harmfully with the materials being added to the collection.
f) Preservation Reformatting: Preservation Reformatting is the task of complete conversion of the material into another format to preserve the library's collections and offer broad public access to at-risk materials. It means duplication of the material into another stable medium or format. “The goal of preservation reformatting is to permit ongoing access to that portion of the information embodied in source materials that has been identified as essential to their continued usefulness for articulated purposes”. “The goal of preservation reformatting is not necessarily to create an exact replacement copy with the look, feel, and functionality of the original”.
The goal of preservation reformatting is to make copies that have the features that are required to meet anticipated needs. This goal may be facilitated by:
i) Instituting a quality control programme using relevant standards and systems to ensure that copies are complete, legible, and free from artifacts;
ii) Confirming that systems are operating consistently at optimal levels;
iii) Inspecting systematically an appropriate number of samples (in some cases 100%);
iv) Documenting processes.
Different physical formats (photographs, negatives, and items with color) with different size, (bound and single-sheet paper materials) and with different characteristics are suitable for preservation reformatting and with the advent of new technologies this list of physical formats and characteristics are expanding day by day.
The archive can think of restricting the access to the analog version of the original item, paper facsimile, or microfilm copy after the reformatting is available for use.
i) Microfilming: Microfilm deals with the reduction of documents to such a small size that it can be read only with the help of optical assistance. It has slow rate of decay and so can be preserved for hundreds of years. But, microfilming has limited access possibilities (no searchable text) as compared to the high use and its competitor digitization. Again, many people consider microfilming as a dying technology taking consideration of the rare nature of microfilming equipment. Microfilming is governed by carefully crafted national standard; can be read by the naked eye provided light and magnification systems are there. These are some of the advantages. The microfilm documents will fulfil the need of creation of duplication from the Master Negative Collection. The master negative will be accompanied by the reel ID, title, date, S. No., etc. In all cases if microfilming is to be followed, then it must adhere to the standards for preservation of microfilming established by the American National Standard for Image and Information Management (ANSI), the Association for Information and Image Management (AIIM), the Research Libraries Group (RLG), and the Library of Congress.
ii) Digitization of Material / Digital Reformatting: Digitization is the process by which analog items (that include books, journals, newspaper, etc) are converted into computer readable text consisting of a sequence of 0s and 1s as a surrogate of the original. It is very hard to retrieve specific kind of information from a huge volume of information as it needs manual scanning page by page and to use the computer for searching all the information together needs reformatting to digital copies. So for the creation of different digital access aids that will include guides, indices, and databases to search and browse the huge volume of information collection, digitization is a must. In short, it will speed up the process of finding relevant information and extend access and assist the preservation. The digital surrogates perform a preservation function by reducing or eliminating the use of the original.
Digital reformatting is guided by the best established practices to ensure that materials are being converted at the highest quality. Reformatting, or in any other way copying an item's contents, raises obvious copyright issues; so before accepting digitization proper attention should be given in this regard also.
A hybrid approach can also be used for preservation, combing the usefulness of both the options of microfilm and digitization at the same time. It addresses long term storage through microfilming while the current use is through digitization. It is the best preservation reformatting option to choose if fund is not a problem for the library.
g) Environmental Catastrophe: The unpredictable disasters like fires, floors, storms, or even broken pipes within the library building may lead to very extensive damage of the collection. These are generally beyond the control of the librarian but it is possible to develop emergency plans for handling the collection and in some cases for preventing the disaster (fires). If a major catastrophe strikes the library, which actions will be taken first and who will take them? The responsibilities must be assigned well before the event.
h) Appointment of Preservation and Conservation Librarian: Some libraries in the world appoint a special preservation and conservation librarian to look after the works of preservation and conservation. Other bigger libraries can also think on the same line. Smaller libraries cannot afford such a full time staff member, but it is still possible for an interested and knowledgeable librarian to be assigned the responsibility on a part-time basis.
Political instability in some regions in the past led to the destruction of many libraries and collections. Libraries as an individual institution cannot do much in this regard.