Preservation of the Documents
The ITS collections in Bad Arolsen are of unique cultural value. To ensure the conservation of the archives for the use of future generations it is essential to restore and preserve the records for long-term storage after digitisation. Apart from the sheer volume of material, the varying grades and condition of the paper documents place great demands on the archivists. At the end of the Second World War there was a perceptible drop in the quality of materials used, as a consequence of which the paper contains high levels of acid and deteriorates more quickly. The fact that the documents have not been stored in purpose-built archives under constant humidity and room temperature has meanwhile become noticeable.
An accurate evaluation of the damage was essential in order to determine the appropriate method of restoration. In the year 2000 the International Tracing Service conducted a damage analysis. A list of priorities was worked out on the basis of this investigation. A proportion of the documents is restored every year, using the list for guidance. The damage to the original documents varies in extent and may involve adhesion, lamination, metal contamination or physical damage, such as tears. The documents have been used as working papers over many decades. This has left its mark.
Even after years of continuous restoration and conservation work, the archives in Bad Arolsen still contain millions of documents that are in a critical condition. As a result, mass processing methods are now used. This is primarily being done through deacidification in a complex chemical process which extends the durability of the paper several times over. Yet conservation efforts also include delamination, stabilising the paper, closing tears, removing any adhesive tape or punched holes, eliminating mildew and restoring ink corrosion. All together, a total of nearly two million items from the ITS inventory have been processed to date. By 2018, all of the documents on incarceration can be restored.