Towards Preventive Conservation of Stone Artefacts in Historical Gardens by Decay Monitoring

While scheduled maintenance is a common practice for the institutions devoted to safeguarding and conserving cultural heritage assets, the prediction of the decay process on stone surfaces is a new challenge in the field. Monitoring is the first, essential step to empower predictive conservation, and technical solutions involving sensors and measurement systems are being widely proposed and tested with the ultimate aim of relating the measured parameters to the decay phenomena. During the activity, we worked on defining a maintenance protocol for stone statues located in historical gardens based on prediction. The final goal is to reduce the degradation risk of cultural heritage assets by means of a smarter planning of conservation works and to optimize budget by avoiding expensive emergency restorations. The paper reports the results of a 5-year-long activity on two marble statues exposed in a historical garden in the surroundings of Florence, focusing on the criteria for de fi ning a preventive conservation protocol. The statues are representative of typical exposure conditions in a sub-urban area, and the assessed alteration/decay phenomena are common to many similar artefacts located in historical gardens.