Throughout its history, the Library has developed techniques appropriate to its preservation responsibilities. Alongside traditional curative care and binding, new activities have been added: prevention and preservation, staff training and awareness-raising, digitization, research, and technology monitoring.
BnF’s laboratory enables a truly scientific approach by developing methods for analyzing materials and the ways in which they age and degrade.
Activities are spread across four distinct sites, coordinated within the Preservation department by a central team based at the François Mitterrand Library (Site François-Mitterrand).
Physical document repairs: consolidation and traditional restoration
Restoring a book block
The restorer replaces or consolidates damaged parts of the book block or binding, adhering as far as possible to the original production process.
The practices and ethical standards involved in restoring books and documents consisting of unbound leaves have evolved over time, leading to five key principles which are accepted by the international community:
- reversibility of processes
- visibility of all interventions
- adherence to old techniques
- compatibility of products and materials used in restoration
- faithfulness and respect for decoration in line with stated principles
Furthermore, the idea of “minimalist intervention” on documents whose stitching and binding are considered “archeological” is gaining ground: in such specific cases, intervention may be limited to reassembling the parts of the work that have come apart. Documents may be microfilmed, and possibly now digitized, either prior to or during restoration.
These processes are performed by chemists and biologists from the Preservation Services Department, and mainly consist of disinfection and deacidification:
Degraded acidic paper
The disinfection unit at the Bussy-Saint-Georges Technical Center, which is open to other institutions, can treat collections infected by insects, mold, or bacteria using ethylene oxide. Such treatments are applied under laboratory conditions.
Books being treated in a deacidification autoclave
As regards deacidification, BnF has worked with the Collection Conservation Research Center (Centre de Recherche sur la Conservation des Collections/CRCC) to adapt an existing process for neutralizing acids contained in paper; a deacidification station using this process has been installed at the Sablé center. In complement to these facilities, the library has been sending documents to an external service provider for deacidification since 2004.