Low cost monitoring approach for the conservation of frescoes: The crypt of St. Francesco d???Assisi in Irsina (Basilicata, Southern Italy)

Environmental monitoring is one of the main diagnostic tools considered for appropriate strategies aimed at preserving cultural heritage. However, monitoring systems are only apparently tools easy to use and manage; actually, they hide several drawbacks including, for example, high purchase costs as well as significant financial commitment related to the management and the data processing. This implies that the use of technologies to monitor cultural heritage is usually limited to high relevance monuments or sites having marked historical-cultural value. In order to enhance the use and the spreading of technologies for the microclimate monitoring, a research activity within PRO_CULT (Advanced Methodological approaches and technologies for Protection and Security of Cultural Heritage) and Smart Basilicata projects was performed. The projects' aim was to test low cost technologies to monitor and manage cultural heritage trying to significantly reduce the acquisition and maintenance costs so as to facilitate wider use of the monitoring systems to safeguard "minor" heritage. Starting from this point of view, an equipment prototype to monitor the indoor microclimate environment of confined environment was planned, taking into account the low cost (LC) approach as the basic assumption. In order to evaluate the LC performance, the system was tested in relationship with the decay problems affecting the frescoes of the crypt of St. Francesco d'Assisi in Irsina (Basilicata, Southern Italy) and the survey data were compared with those recorded by a standard commercial system (CS). All this in mind, the article discusses the comparative analysis of the two microclimate monitoring systems in relationship with the decay problems of frescoes hosted in the crypt of St. Francesco d'Assisi. The system comparison shows a quite complete matching of the thermo-hygrometric values. Furthermore, the survey puts into evidence as the microclimate conditions in the crypt are not suitable for the conservation of the frescoes. The studies based on the microclimate analyses together with other in situ surveys allowed to propose possible technical solutions to mitigate the decay risk related to the artistic heritage. (C) 2016 Elsevier Masson SAS. All rights reserved