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8 Discussion of Fir ngs This discussion considers the facts that the committee has gathered concem- ing the deterioration of the collections of the National Archives and the conditions that have contributed to this deterioration. The committee has adopted some general recommendations, and these are discussed first. The second section con- cems the possibility of mass treatment for NARA's holdings, in particular environ- mental controls and deacidification, and there are recommendations in those areas. Finally, there is a discussion of the coordinated steps the Archives can take to determine when preservation action is advisable and which methods of preser . . vatlon are appropriate. NATURE OF THE PROBLEM The National Archives, founded in 1934, is a young institution. Although some of its records are more than 200 years old, the collection is not old in terms of the history of paper records or of paper itself, for some papers have lasted many hundreds of years. The bulk of the collection was created during the past 100 years, however, and therefore has accumulated the problems associated with the decline in purity of western papermaking that began in the 17th century. This decline accelerated in the mid-19th century when manufacturers, responding to ever- greater demand, began to produce cheaper papers dangerously prone to oxidative and hydrolytic reactions. In the mid-20th century, copying processes were devel- oped that used paper that deteriorates even more quickly and, in some cases, suffers relatively rapid image loss. As these sorts of records have begun to reach the limits of their durability, the problems of failing paper and vanishing image are becoming of concern to the world's libraries and archives. This concern is cer- tainly appropriate, but dire predictions about the limited useful life expectancy of 19th- and 20th-century papers have all too often led to panic and a sense of help- lessness, sometimes producing hasty, unthinking responses rather than the realis- tic, planned course of action that is needed. 79

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80 PRESERVATION OF HISTORICAL RECORDS Condition of the Collection The collections of the National Archives contain a great range of different kinds of damaged or deteriorating records. Inspection by members of the commit- tee revealed that papers seem to be in worse condition at the beginning or end of a group or along the edges {that is, where they are most handled or most exposed), whereas the condition in the center of a group seems to be good. The sorts of damage are what would be expected: tears, discoloration, loss of fold endurance, and image loss. The volume of large collections of damaged or deteriorating paper as a percentage of the total volume needing remedial action is small. Most of the records that need treatment occur as single sheets or in small groups. NARA reported the following points of concern: A large percentage of the collection is quite acidic, with a pH less than 5. 160 million sheets have already suffered major damage of one form or another; a very small percentage of records cannot be handled at the present time. 270 million sheets were produced by quick copy reproduction processes such as Thermofax and Mimeograph during the 1940s, 1950s, and 1960s, and these are rapidly deteriorating; loss of information in the earliest of these records is expected within 10 years. 100 million sheets are subject to mechanical damage by frequent handling. The estimated total number of these records at some risk of loss of informa- tion value is 530 million, or over one-sixth of the entire collection. Prevention of Future Detenoration Besides environmental controls, which are the subject of a separate section, some improvements can be made in current practice that would help to prevent future deterioration of the sort now evident in NARA's collections. In particular, the adoption of media standards where they exist, and their development where they do not, would increase the future volume of stable records, while less fre- quent handling would increase the lifetime of all NARA's records. Paper and Film The compositional factors that most influence the durability of a paper are the quality of the fiber and the level of acidity. The standards in these areas are well known, as are the aspects of the manufacturing processes that affect achievement of the standards. These standards are given in detail in Chapter 4. It is only recently, however, that there has been an economic advantage to manufacturing, and hence to purchasing, permanent papers. Papers of archival permanence are now available at a cost reasonable enough to encourage the federal government to use such paper for a broader range of documents. There also exist standards for photographic film in the areas of film type, processing, and storage conditions. These standards, adopted by the American National Standards Institute, are given in detail in Chapter 5, and the National Archives should apply them as a matter of course, while keeping in mind the need to maintain good resolution, contrast, framing, and completeness.

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DISCUSSION OF FINDINGS 81 Magnetic Tape and Optical Disk In the areas of magnetic and optical recording media, the committee found that there are three problems that prevent records of these types being considered archival. The first is the pace of technological development, which has the result that changes in media and hardware require periodic conversion of older records into newer formats. The second problem is that the life expectancy for magnetic tapes is estimated to be 10 to 20 years, and a similar lifetime is projected for optical disks. The third concerns the lack of standards in certain areas, which results in incompatibility of systems, unpredictability of product lifetime, and uncertainty . in p annlng. Chapters 6 and 7 point out two difficulties that result from the pace of devel- opment. First, rapid development requires systems conversion, and second, there are the attendant problems of the future availability of older hardware and the preservation of software and documentation necessary to do the conversion. Nei- ther of these problems has an obvious solution, but study should be undertaken now to prepare for the future difficulties that will result from the inevitable deposit of large volumes of machine-readable records with NARA. The life expectancy of the media also makes periodic recopying necessary. A medium might be archival and yet require recopying, but the frequency of recopy- ing could be less frequent than the 10 to 20 years that magnetic and optical media now require. In addition, deterioration in these media is not easily perceived, which means that even more frequent reading would be necessary. Data compac- tion in this case is a two-edged sword because, although it allows processing large amounts of data, even small-scale physical deterioration in the media will have a large-scale impact on the condition of the information. Chapters 6 and 7 also point out that there are no standards for the binder systems used in manufacturing magnetic tape and that there are no standards for optical disks in the areas of format, hardware, and materials. The fact that signifi- cant recording on these media is now being done in the federal government sug- gests that work on standards needs to be speeded up significantly and that it is important for the government to take a lead in establishing such standards. The implications of this concern for preservation action by NARA are discussed later in this chapter. Handling It has been shown that the rate of natural aging of paper that has been sub- jected to improved environmental conditions is not a linear phenomenon. Paper that has reached a point of zero folds may last indefinitely as an integral sheet if left relatively-undisturbed and in a suitable container in controlled conditions. It is extremely rare to find disintegrated paper fragments in a box of records without a history of use. Unfortunately, there is no current standard for determining the difference between frequently and infrequently used archival documents. The section, A Systems Approach, later in this chapter contains a further discussion of this ques- tion. No matter what the definition for frequency of use, however, less use means longer life for paper records. It is possible that certain additional finding aids may

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82 PRESER VATION OF HIS TOPICAL RECORDS reduce use in selected groups of records, and it might be useful for NARA to investigate the effectiveness of new finding aids in preservation. NARA should also encourage better indexing by the depositing agencies. Nevertheless, the cost of comprehensive indexing is so high that it cannot be recommended simply as a preservation strategy. Apart from deterioration of media, however, handling may have other nega- tive consequences. As discussed in the description later in this chapter of the decision procedure for preservation action recommended by the committee, one of the criteria that affects preservation strategy is the cohesiveness of the record. There, the subject is the difference in verification of copying appropriate to files that contain redundant information as opposed to files whose individual docu- ments hold unique places in the record. In the latter cases, the loss of a single document, or perhaps even part of a document, may have a significant effect on the information value of the file. Frequent handling of such files increases the risk of loss, even when the medium itself is in good condition and is expected to remain in good condition in the future. Copying at the discretion of the archivist may be justified in these cases. General Recommendations The committee feels that several recommendations covering issues of general concern are appropriate: A general improvement in the quality of paper used by the federal government would be an important step in minimizing future problems of the sort now experi- encedby the NationalArchives. Since permanent papers are becoming available at a reasonable cost, the government should use such papers for records that have permanent value. Archival standards are available for papers and photographic films. Archival standards are also available for electrophotographic reproduction. NARA should ensure that the records it creates or copies with these media or processes meet these standards. Archival standards do not exist for magnetic tape or optical disk or for the reproduction of records on such media. Since these media are currently being used by the federal government, and since their use will greatly expand in the future, NARA should promote the development of standards for these media at the earli- est possible date. Major deposits of machine-readable records exist. If these records are to be useful to future research at the National Archives, NARA should be prepared to accession them and to preserve the information they contain. OPTIONS FOR MASS TREATMENT The difficulties associated with the distribution of damaged papers in the NARA collections were mentioned previously, and this subject is treated in greater detail later in this chapter. There still remains the question as to whether large- scale treatment might be appropriate for the records as a whole. The committee

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DISCUSSION OF FINDINGS 83 looked at two aspects of this problem environmental control and mass deacidifi- cation. Environmental Control The National Archives has been relatively forward-looking on environmental controls; air conditioning was installed in the 1930s. In more recent years such concerns have expanded to include areas beyond temperature and humidity. Fur- thermore, while papers in the Archives building are comparatively well housed, their histories are spotty at best. Materials that are stored for years in agency files, and then for more years in various federal records centers, are subject to frequent changes in temperature and humidity and to little if any controlled protection against pollutants. These records arrive at NARA carrying their history with them. Wide fluctuations in temperature and humidity, especially familiar in such cities as Washington, are a major contributor to the rate at which modern papers deteriorate. Establishing the rate of deterioration in records is a key requirement for planning preservation strategies. Unfortunately, few scientific data exist for determining such rates. However, it is certain that moving into the Archives Building was salutary for the vast majority of NARA's 3 billion records and that improved conditions have slowed the rate of deterioration. The improved environ- mental controls that NARA is now planning to implement will slow the rate of deterioration even further. Although questions remain concerning the precise standards for environmental controls, the committee feels confident in endorsing the standards recommended in Chapter 3. The committee notes that the critical environment is that at the surface of the paper and that the greater part of NARA's collection is boxed. Unfortunately, very little is known about the microenvironment of the archival storage container. Indeed, what is known suggests that good containers may obviate the need for the most exacting and costly macroenvironmental control; on the other hand, it is also known that the close proximity of acidic materials is undesirable. The com- mittee feels that a substantial research effort should be conducted in this area, especially as NARA is planning to install compact shelving that will further encase the records and may significantly influence the effectiveness of any improved macroenvironmental control system. Mass Deacidification A high percentage of NARA's 3 billion records is categorized as quite acidic, with a pH of less than 5. While this condition can affect the physical strength of documents, it does not ordinarily result in the destruction of documents on its own (acidic inks are another matter) . Deacidification, however, cannot restore the strength of damaged paper, and the process itself could result in further deteriora- tion. The point of a mass deacidification program is to treat the papers in bulk, but this is not an option for the National Archives because its records present a great mix of different types of documents that could not economically be separated. The deacidification process would result, for example, in heat damage to Thermofax documents and solvent damage to some inks. On the other hand, there could be an

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84 PRESER VATION OF HIS TOPICAL RECORDS added benefit in deacidification in the future for collections of records that have good physical strength properties. The cost of using the process as a preventive, however, is not justified at this time. Recommendations on Mass Treatment The committee developed the following recommendations regarding mass treatment: The standards given in Chapter 3 for temperature, humidity, and pollutants should be implemented {see Tables 3-4 and 3-5 for specific standards). NARA should conduct a study of archival storage containers and microenvi- ronments, including boxes, folders, and polyester encapsulation, with a view to understanding the maximum benefit that can be obtained from particular materi- als and designs. The committee feels that this is an underexplored area that may yield results highly significant to NARA's preservation efforts. NARA should not undertake a mass deacidification program at this time but should monitor the development of deacidification processes. A SYSTEMS APPROACH This section describes a general procedure for preservation action in effect, a decision tree for choosing which records need treatment and what treatment to give. The first part of the discussion concerns the media that are appropriate to archival copying. The next section describes that procedure itself, together with its limitations and subcategories. Finally, there is a discussion of implementation. Suitability of Preservation Copying Media The holdings of the National Archives are predominantly paper-based and will remain so for the foreseeable future. The question remains, however, of what to do with records at risk. The committee examined alternative media onto which records might be copied: Copying onto magnetic or optical media, which would have the advantage of compaction and potential ease of transmission and future manipulability; Copying onto paper, since archival standards for paper and for electrophoto- graphic copying exist; and Copying onto microfilm, which offers the advantage of compaction and for which archival standards for both film and microphotographic processes exist. Copying Onto Magnetic or Optical Media Although they are quite useful and stable for time periods of 10 to 20 years, current flexible magnetic recording media suffer from recognized material degra- dation processes that make them vulnerable to large-scale information losses over long periods of time. Their advantages of rapid access times and adaptability to large-scale data manipulation are not particularly relevant to archival needs. Their

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DISCUSSION OF FINDINGS A? .'. ~ :~,$ 85 ? ~ - ~ ~,<.~'.'~ ..? l A.. Chamber for mass deacidification of books. The deaciclipcation process can add years to the life of endangered books butisnotnowpractica~for preservation of diversified collections of in~vidua] documents.

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86 PRESER VATION OF HIS TOPICAL RECORDS ability to be erased or updated is, in fact, a liability in archives. Material degrada- tion processes in current optical disks are not well understood, and the technology is not sufficiently developed to recommend them for archival use. Both magnetic tape and optical disk storage are vulnerable to the problems of hardware obsolescence and software and documentation loss discussed earlier that could render data unreadable even if it still remained preserved on the primary medium. This is a serious concern for archives that must plan for the ages, as opposed to libraries that must serve a variety of users primarily interested in rapid access and retrieval. Copying Onto Paper or Microfilm Standards for archival-quaTity paper and electrophotographic duplicating pro- cesses have been developed that are adequate for the National Archives to use in establishing and maintaining quality control for copying damaged documents onto paper. In addition, the Tong history of generally satisfactory use and the ability of current holders of large silver-based microfilm collections to maintain adequate quality control make this medium archivally acceptable. It is possible to transfer records from paper or film to magnetic or optical storage media using automated systems, so that conversion in the future should not be labor-intensive. Recommendiations on Archival Copying The committee recommends the following with regard to copying media: The media that are appropriate for archival preservation are paper and photo- graphic film, and the processes appropriate to copying using these media are archivally standard electrophotographic processes {for papery and silver-based micrographic processes {for film). The materials and technical problems inherent in the use of magnetic and optical storage media and the lack of suitable standards for archival quality make their use as preservation media for archival storage inappropriate at the present time. Decision Tree for Preservation Action The committee has organized its recommendations for action into the deci- sion tree shown in Figure 8-1. Here, the collection is described primarily by the frequency of use and the physical condition of the documents. The definitions of use and condition are discussed first, followed by paragraphs giving the commit- tee's recommendations for each subcategory. Preliminary Considerations It seemed initially that the question posed by the National Archives was purely practical: What recording medium is most appropriate for the long-term preservation of the nation's records? It became clear, however, that an answer to this question was not possible merely on the basis of facts about materials science

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88 PRESERVATION OF HISTORICAL RECORDS alone. The original question requires consideration of problems such as media stability and lifetime, reproducibility, cost, etc., but the committee discovered that determining the appropriate application of a particular medium frequently requires decisions based on archival criteria. The National Archives must clarify the key criteria of use and condition and must improve the statistical description of its collection before remedial action can be taken to improve the condition of damaged records. Cntena for Use Although frequency of use here must be defined within an archival context, if it is to be employed to justify preservation action it still must correspond to a reasonable concept of use. The average document in the National Archives is seen perhaps only once every 100 to 200 years. Frequent use might then be defined as anything more than twice a century, but this level of use does not justify preservation action. As another example, there are popular series made up of case files with good indices whose individual documents are not frequently handled because the nature of the file and the depth of the indexing lead the researcher directly to the desired papers in most cases {Schofer, 1986~. On the other hand, there are correspondence series of great historical interest that are examined document-by-document by several researchers in a year. It is these latter series that qualify for preservation action because of frequency of use. NARA does not have a well-defined basis for clearly identifying documents that are frequently used in this sense. NARA must develop such criteria to establish priori- ties for copying. Cntena for Condition Documents in satisfactory condition are those that are reasonably expected to retain their information value for the foreseeable future, whereas documents in unsatisfactory condition are those that are at risk of loss of their information value even without being able to say precisely when. At the moment, NARA cannot easily distinguish between these two categories to allocate preservation resources and to adopt reasonable preservation schedules. NARA will need a specific guideline for life expectancy, say 100 years, that should be related to the time before which the document will be seen again. Given this time period, an archivist should be able to say of any document or series whether it will retain its information value at the end of that period. If it will not, it should be scheduled for preservation. NARA will also need criteria that will allow it to say whether one kind of damage is more serious than another, so that faster or more extensive treatment can be scheduled. Problem Distribution A potential difficulty in any large-scale preservation effort was pointed out earlier: The majority of the records at risk of deterioration exist as isolated documents distributed at random among the National Archives holdings. Only a much smaller fraction exists as identifiable series of records. Specific data on the number of documents in these categories would be valuable in constructing a general plan. The type of information NARA needs can be obtained only by actual assess- ment of the conditions of individual records series. It is obvious, of course, that NARA cannot perform an item-by-item, or even container-by-container, survey of its collection. There are procedures, however, that would improve the informa

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DISCUSSION OF FINDINGS 89 lion available for preservation planning. First, records must be kept of the condi- tion of papers that actually are seen or used by staff and patrons, much as in the experimental intercept program described by Calmes et al. {1985~. In such a pro- gram documents should be screened for their condition before being given to the person requesting them, and records should be kept of that condition. Second, the Archives is currently designing a program to improve the maintenance of its holdings, which may result in the construction of a shelflist. It may be possible to generate statistical information about the collection from such a shelflist. Explo- ration of this possibility should be included in the planning of the program. Recommendations for Preservation Action The committee recommends the following as preservation actions: The National Archives should institute procedures immediately that will yield statistics concerning damaged records that are useful for long-term preserva- tion planning and for deciding treatment priorities. The committee suggests that statistics be kept that reflect the condition of records used both in the reading rooms and by the staff and that these statistics be supplemented by the informa- tion generated by the ongoing maintenance operations. The National Archives should establish criteria for frequent and infrequent use and for satisfactory and unsatisfactory conditions so that priorities in treat- ment may be assigned. Preservation Actions by Categories Frequendy Used, Satisfactory Wonton Frequently used files, although currently in acceptable condition, are at risk simply because of their use. This is based on the assumption that the most frequently used documents contain infor- mation of greater-than-average value and will continue in high use in the future. The increased risk for these frequently used materials justifies monitoring to allow prompt action should their condition change. Monitoring probably can be conducted most efficiently at the time of use and could make use of researchers in identifying marginal condition. As increasing numbers of documents within a file are identified as damaged, the possibility of filming the entire file should be considered. Frequently Used, Unsatisfactory Con~non Frequently used files that are in unsatisfactory condition demand timely preservation that can be accomplished most readily by microfilming. The greater the frequency of use, the lower the degree of risk acceptable before action is taken. For all microfilming, the verifica- tion of the images should be done at a level specified by an archivist, preferably with the advice of a committee of users who can help determine the degree of loss if some small fraction of the images is lost. Many records contain much redundant information, so little risk of real harm would be associated with the loss of a single image. Other records are valuable because they are unique sources of certain information, and thus loss of even part of a single image would cause serious harm. After appropriate verification, NARA would dispose of the paper documents.

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go PRESER VATION OF HIS TOPICAL RECORDS Infrequently Used, Satisfactory Condition Documents that are seldom used and in satisfactory condition obviously need no particular attention other than being included in the continuing collection of statistics on use and condition to better characterize the holdings. Infrequently Used, Unsatisfactory Con~hon For those files classified as infrequently used and also in unsatisfactory condition, a further distinction should be made on the basis of whether the damaged documents occur as isolated sheets or as large groups of similarly poor-condition papers. Single damaged sheets should be electrophotographically copied using materials and processes that con- form to archival standards, and NARA may dispose of the originals. This can be done on a continuing basis as damaged sheets are identified by users. Damaged sheets that contain notations in colored pencils, different inks, or watermarks may not retain these distinctions after copying. These documents may be pre- served by interleaving between sheets of polyester film. Extensive files of damaged or poor-quality documents, such as mimeograph copies, should be microfilmed. The level of verification should again be deter- mined by an archivist but may be done to a different standard than in the case of frequently used documents. NARA should dispose of the original documents when verification is complete. Implementation Implementation of the decision tree will require that the National Archives commit itself to a very intensive program of quality control and verification of copies. Each step in the electrophotographic or micrographic process will need rigid standards of performance, and the work produced under these standards will need continual inspection. In some cases, especially those in which infrequently used materials are being filmed in series, it may be sufficient to verify the photo- graphic quality while only sampling for content verification. On the other hand, frequently used materials may need to be verified frame-by-frame. strategy: Recommendlahons on Preservation Strategy The committee recommends implementation of the following preservation The National Archives should adopt the decision procedure and the recom- mendations on treatment and records disposal that are embodied in the decision tree, Figure 8-1, with the caution that this recommendation cannot be separated from the following one. Portions of the proposed preservation plan include disposal of original records after copying. In these cases, the copy will be the record. The National Archives must establish in perpetuity a program of effective quality control and verification of copying.

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DISCUSSION OF FINDINGS REFERENCES 91 Calmes, A., R. Schofer, and K. R. Eberhardt. 1985. National Archives and Records Service lNARS) Twenty Year Preservation Plan. NBSIR 85-2999. Gaithersburg, Maryland: U.S. Department of Commerce. Schofer, R. E. 1986. Cost Comparison of Selected Alternatives for Preserving Historic Pension Files. NBSIR 86-3335. Gaithersburg, Maryland: U.S. Department of Commerce.

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