An index for the evaluation of microclimatic conditions inside museum showcases

A new index useful in comparing microclimatic conditions inside museum showcases is here presented. The advantage of the index consists in its independence from thresholds that are usually fixed by the norms or by the experience of curators. The procedure to compute the index is described in detail, and it is easily reproducible. Microclimatic conditions inside showcases have been compared using the proposed index in a library hall of the Museum of Physics, University of Turin, Italy, during two temporal periods longer than one year. The results show that the index correctly identifies the favorable or critical conditions for conservation.