The conservation of sacred art: a case study purpose to search for an index of correlation between particle concentration and mass of fine dust.

The present work concerns the study of the concentration of total suspended particulate (TSP) mainly from uncombusted residues of smoke candles or incense. The aim is identifying the most critical situations for the preservation and conservation in situ of works of sacred art, normally exposed to the veneration of the faithful. These peculiar type works of art can not be placed out of context . This because the artifact is an object of worship for many years , it is often object to physical contact by the faithful , subjected to frequent expositions and microclimate changes. Also it suffers an intensive smoking derived from incense and votive candles. The experimental analysis carried out by the authors concerned the monitoring of TSP in the niche of the SS. Crucifix in the Church of St. Papino in Milazzo (ME). The niche, as well as the wooden statue of the Crucified contained, includes a great variety of objects of different nature: bone relics, scrolls, tapestries, precious votive offerings. At present all this precious material is been pouring in clear degradation. The monitoring of PTS was performed using a particle counter and a extractor plug with a collection filter for the gravimetric test. Tools have provided quantitative data of the number of particles per unit volume and the value of particles’ mass per unit volume, respectively. Then it was possible to determine a correlation marker between the two different instrumental control methods. SEM-EDAX analysis, applied to the samples collected, also provided detailed indication on the nature of various inorganic components stored on filters. The research results will lead to the definition of new screening equipment useful for particulate matter filtering or suppression, specifically in churches. These devices can be validated by subsequent and more detailed monitoring surveys.