Showcases: a really effective mean for protecting artworks?

Field and laboratory tests have been performed to analyse the response of s howcases to environmental factors. The following properties have been teste d. Thermal damping. Greenhouse effect and IR absorption of the materials mo st commonly used for panes. Impact of different types of light sources. Hum idity buffering capacity and rate. Inside/outside exchanges and leakage. Pe netration and deposition of airborne particles. Advantages and disadvantage s of airtight and non-airtight showcases in view of protection against dust , corrosive self-outgassing of VOC and microbiological infection and growth . A proposal is made to indicate all of the case characteristics, and their response to the ambient, with appropriate indexes, which represent the lev el of quality in view of the specific problems of the user. A quantitative evaluation of each index quality level is also discussed. (C) 2000 Elsevier Science B.V. All rights reserved.