Experts have found that the best way to store mountains of historical documents is not on computers -- but on paper. In a report to the National Archives released this week, experts found that laser discs, semiconductor chips, and magnetic computer tape all have basic flaws and are unsuitable to store the information on historic documents. The best way to preserve these priceless treasures, the panelists say, is on special paper.
The experts assembled by the National Research Council (NRC) recommended that the federal government begin using better paper for important documents to head off future preservation problems.
All the high-tech options have several basic flaws, they say. Either the medium used to store information (such as magnetic tape) has a limited life span, or the computer hardware and software is quickly outdated as new technology is developed. The National Archives is already having trouble using some recorded material because the machine needed to ``read'' the information is no longer available. Paper, on the other hand, can be made to last for centuries and needs nothing but a pair of eyes to be understood.
Today's equipment isn't expected to stay in service for more than 10 to 20 years. According to the report, two conclusions can be drawn: ``first, the recording media may well outlast the hardware; and second, it will become necessary to recopy the tape record every 10 to 20 years on an ever changing, propably incompatible, new machine with a new format.''
For the National Archives -- with over 3 billion items to store -- and other libraries and private holdings, the notion of converting all their historical data five or six times a century would bust their budgets. The scientific panel did say, however, that high-tech applications may make sense for small holdings, or for information that is needed quickly or used often. The Library of Congress, for example, is using optical disc technology because its primary concern is with easy access, not preservation.
The National Archives has anticipated the increased storage need to maintain paper records, and is in the process of installing new, more compact shelving in its Washington building, as well as drafting a proposal for a new building that must be approved by Congress.
Of the 3 billion pieces of paper the archives has been entrusted to preserve, 160 million sheets have already suffered damage, and 530 million more are at risk of losing the information stored on them. Some of the most endangered materials are mimeographs and thermofaxes made in the 1950s and 1960s. Because of the paper, inks, and printing technology used, these documents deteriorate to illegibility in a relatively short time.
The NRC report, entitled ``Preservation of Historical Records,'' does not deal with historical documents with intrinsic value -- like the Bill of Rights or the Declaration of Independence. Only 25 percent of the National Archives' holdings have such a value. The vast majority of its records are only important for information. The report also does not deal with the storage problems which would result from records on paper.
It is possible to produce a high-quality paper that can survive for centuries. The scientists point out however, that even high-quality paper must be stored properly to ensure against long-term damage from air pollution. Pollutants common to most urban areas (ozone, sulfur and nitrogen dioxide, and small particles such as dust and soot) are difficult to remove from building air conditioning systems and can cause severe damage.
For example, books stored in Antarctica from 1912 to 1959 appeared new, while identical books subject to higher levels of air pollution in London showed extensive deterioration. The scientists found that storing documents in acid-free file folders and boxes may provide more protection than expensive air conditioner filters.
Despite all the electronic storage options available, the panel simply recommends that important documents be photocopied on permanent (archival quality) paper, microfilmed, sealed in protective materials, or treated chemically to remove acid from the paper. These and other precautions ``will preserve most papers for centuries,'' the study found.