Vibration as a Hazard During the Transportation of Canvas Paintings

The assessment of vibration levels that cause damage to canvas paintings travelling on loan has been hampered by the lack of direct measurements of the dimensional change of the canvas. The application of triangulation laser displacement sensors in this study has allowed direct, continuous in situ monitoring of the vibration of canvas during packing, handling and transporting by road of three nineteenth-century oil paintings from the collection of the National Museum in Cracow, Poland. The measurements showed various levels of vibration primarily influenced by the packing method: paintings wrapped in tissue and transported in soft cardboard boxes were better cushioned from the vibration than a painting rigidly fixed in a wooden case. However, increased levels of vibration were always measured during packing the paintings and transferring the cases or boxes to and from the road vehicle, which emphasizes the need to train staff to handle the paintings with care when they are still in the museum. The strains induced by the vibration levels recorded were much lower than the critical levels of tolerable strain for the nineteenth-century canvas paintings quoted in the conservation literature. Therefore the paintings are unlikely to be endangered by fracture or fatigue damage under the transportation conditions monitored