Viviers townhall in Ardeche, recently took over an ancient bishop’s palace, a beautiful building from the early eighteenth century. Beautiful inlaid parquet with geometric decoration, 86 m2, needed restoration. Wood was attacked by fungi (merule or dry rot fungus) and the thickness of the layer of mosaic wood was reduced, in some areas, to a few millimeters. In 1998, the wood panels were removed one by one to be sterilized, impregnated and consolidated by gamma irradiation in Arc Nucleart laboratory in Grenoble, before being reassembled in 1999. The rooms of the former episcopal palace welcome now cultural events.
Remains of a fortified settlement dating back around 1000 A.D. have been found on the shores of Lake Paladru in Isère. Charavines site, searched for twenty-five years has delivered a considerable amount of furniture : more than 2000 pieces, exceptionally well preserved following the rise of the lake level that inundated the site. How to preserve so much humble objects of everyday life, valuable for what they reveal? The treatments were adapted to the nature of objects, metal, leather or wood. The waterlogged woods go into dust when they are dried. They were therefore impregnated with a resin that has replaced water, and then underwent gamma irradiation that had polymerized the resin. The best part is probably a wonderful saddle pommel carved in wood that has been well preserved.
The process of consolidation by irradiation is particularly suitable for highly degraded objects, where the use of traditional techniques would be little or not effective. The consolidated wood can be worked like a hardwood. An old middle-age virgin can now support the restoration work that was forbidden before banned because of its fragility. Furniture highly affected as statues of stone and plasters are saved.
Disinfection requires less intense gamma radiation that hardening by polymerization. When the mummy of Ramses II was received at the “Musée de l’Homme”, a French museum, to be treated, it was infested with larvae and fungi. Sixty species of fungi were counted. The glorious pharaoh of the nineteenth dynasty, winner of the Hittites, made the journey to the “Commissariat à l'Energie Atomique” in Saclay, which had an irradiator capable of getting the pharaoh rid of his pests. On May 8, 1977, the mummy was given a dose of 18,000 Grays (Gy) in two sessions of 6 hours, without having to leave his sarcophagus. Back in Cairo, restorers gave him, the final touch, putting back order in the pharaoh's hair and in the royal linen drape.
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