Storing the collection
Appropriate storage of objects is a crucial element of the Museum’s everyday effort to take care of the collection. Using scientific study and conservation knowledge, steps can be taken to prevent damage before it starts or to preventive further deterioration from taking place.
Preventive conservation plays a role both in the galleries and
exhibition spaces and in the Museum’s stores and studios, where
conservators and scientists have to keep a constant eye on
In the galleries, ultra-violet light has to be filtered out by using screens on windows, temperature has to be stable and humidity levels kept constant. Display cases might be air-tight, but all of the materials used in their construction have to be tested carefully to make sure they are not potentially harmful to objects. For example, the use of wood and wool fabrics in the construction of cases must be avoided as gases given off by these materials can corrode metal and other objects
Sensors are used both in stores and in galleries to make sure the environmental conditions are kept just right. They are used to measure such things as the relative humidity and temperature every 15 minutes and to transmit the data to computers so that conservators, scientists and curators can monitor conditions in real time and keep a constant eye on
The environment to which objects are exposed has to be carefully controlled and monitored because specific materials have been found to be vulnerable under different conditions. For example, some artefacts made out of bronze or copper alloy can suffer from what is known as ‘bronze disease’ if the humidity around the artefact is not kept at below 35%. If it was allowed to increase, these objects would start to corrode.
Glass is generally a very stable material, but some glass, including some made in Venice, Italy is not. Inappropriate humidity levels can cause the salts in Venetian glass to start coming out of it. The salts take up moisture from the air, forming surface droplets and this condition is therefore known as ‘weeping glass’.
Organic materials, such as feathers, wool, fur or skin, are at risk from another potential danger: pests. Moths or carpet beetles will eat such materials, making holes in them or worse. However, pesticides cannot be used on museum objects as the long term effect that these chemicals might have on the objects is unknown. Instead prevention, once again, is the cure.
All stores and cases have to be kept perfectly clean because dust attracts insects. Windows have to stay closed, doors have brush seals around them and sticky traps catch any successful invaders.
Insect traps are constantly monitored to make sure that pests haven’t got through these tough defences. If pests do get through however, a huge freezing chamber is used to take the infested material down to minus thirty degrees Celsius, which kills the insects.
Scientists and conservators at the Museum have built up a tremendous amount of knowledge over many years of how the materials in ancient objects behave over time and can best be looked after. However, they face a major challenge when it comes to caring for the more modern artefacts collected by the Museum.
These objects, such as those making up the art installation La Bouche du Roi, are made from modern synthetic materials and plastics for which the long term stability and behaviour or the factors which might cause damage to them is not yet known.