Irradiation as a Method of Salvation of Cultural Heritage Objects Under Massive Jeopardy

Cultural heritage artefacts made of organic materials are susceptible to deterioration caused by the action of insects, moulds, fungi and bacteria. The problem of biodeterioration becomes especially acute after natural catastrophes and weather inclemencies, or after human activities conducive to an abrupt development of pests. Usually a large number of objects are imperilled at the same time and their sheer number aggravates any organized preservation effort. Irradiation has proven an effective method of preservation under the circumstances, e.g. for the prevention of massive proliferation of fungal infestation of books wetted by flood. War destructions in Croatia 1991 - 1995 seriously jeopardized many cultural objects. Their treatment by 60Co gamma rays in the Radiation Chemistry and Dosimetry Laboratory of the Ruðer Boškoviæ Institute played a significant role in the prevention of massive biodeterioration. In co-operation with the Croatian Conservation Institute, one third of 5000 evacuated objects, mostly polychromic wooden sculptures, were irradiated for desinsection and disinfection, enabling their joint accommodation in depots until restoration. This contribution to the preservation of jeopardized cultural heritage objects has been recognized internationally as a specially significant and successful case of the application of irradiation to cultural heritage. The presentation describes in more detail the preservation and restoration of the altar of the Holy Cross from the church of the Blessed Virgin Mary of the Snow in Kamensko.(author)