Page 300 - Manual for Activities directed at the Underwater Cultural Heritage
P. 300

many artefact materials, the ideal storage is at low temperatures (around 15°C) and a relative humidity (RH) that lies between 35% to 70%. Metals should be stored in a range of 15° to 24°C, and below 35% RH. Organic finds, such as objects of leather, textile, wood or bone must be dried before deposition in the archive and stored at 18° to 22°C and 45% to 55% RH.
The drying process is where the challenges in conservation are the greatest. Material from a saline environment must be thoroughly desalinated, to keep it from attracting moisture. Some packing and storage materials are better than others. Acid-free packing materials are preferred in international standards.
An alternative solution is to conserve artefacts in submerged depots. In this form of wet storage that is sometimes chosen for big timber objects, the artefacts are conserved in a wet environment that is similar to their original site context or in freshwater tanks. Yet again, the depots need to be controlled for light, temperature and whether the water is infested by organisms that feed on the wood. Some repositories control the tank environment with carefully selected living fish. Other institutes include reburial below the groundwater table as part of their archiving policy.
Location
Appropriate documentation, archiving and storage are of fundamental importance. The project archives must be stored in a place that provides the best possible conditions to prevent degradation of materials it contains. Moreover, it should meet safety requirements, while at the same time assuring availability to the interested public. Finally, the storage location should meet the best possible conditions with respect to temperature, humidity, lighting and exposure to the risks of natural disasters. Specific environmental desiderata may vary for the different materials that the archive will contain, but all will profit from stability. While it may be necessary to apportion the archive to different rooms with different indoor climates, it is nevertheless preferable not to have these rooms too far apart.
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Curation of project archives



























































































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