The air treatment system in the depots was not working correctly, giving mold a chance to grow. Mold likes a moist and warm environment. To better control the climate and prevent further damage, the museum installed dehumidifiers, but approximately 7,000 objects were already contaminated and had to be cleaned. As a result, the museum has built six workshops in the exhibition hall for the restorers of Art Salvage, where visitors could look at the work through the windows.
Measurement method and outcome
Tests had to be carried out to determine the best cleaning methods for the various works of art made from very different materials. Mold contamination cannot always be determined visually, so areas without fluffy stains must also be cleaned.
To test whether a cleaning method was effective, measurements were taken before and during the treatment with a luminometer to test the presence of adenosine triphosphate (ATP) both before and after cleaning. ATP is a molecule left behind on a surface by organisms: a contaminated surface, therefore, gives a high measurement, a clean surface a low measurement. By taking samples before and after cleaning, it can be shown how successful the cleaning has been.
Project in the spotlight
It soon became clear from the measurements that vacuuming was not sufficient in many cases. Cleaning with a vacuum cleaner is considered one of the most effective methods of removing mold and works well when the mold is dry and powdery. The white and black mold found on the objects could often be cleaned, while the brown and yellow mold proved to be more persistent. The spore population was further reduced in these cases with alcohol or water-based mixtures.
The wet cleaning methods were always first tested on, for example, the back or bottom of an object using a cotton swab. Art objects can be very fragile and due to the wide variety of materials and finishes, each object reacts differently. Art Salvage has therefore deployed a team of restorers with different specializations such as paintings, stone, ceramics, paper, visual media and plastics.
The condition of all objects was registered during the cleaning process, and special cases were photographed. All contaminated objects have now been cleaned and safely stored in temporary storage. When the air treatment system is adapted, all objects are returned to the depot, where they are then safely stored for generations to come.