EN
In our activity in the Foundation for the Protection of Monuments in Warsaw we frequently encounter problems concerning the extermination of insects which cause damage to wooden historical objects. Numerous expert opinions on the state of the relics, a survey of professional literature on the subject as well as previously conducted laboratory experiments have made it possible to voice our opinion about the effectiveness of various methods applied in the battle against insects, conceived as technical sources of devastation of wood. The most frequently encountered construction material of Polish wooden architecture is coniferous — predominantly the pinus silvestris L. and the abies alba Mill, (pine and fir). Interiors also display oak (Quercus sp.) and linden (Tilia sp.). Among 12 species of insects the most frequent and most dangerous are Hylotrupes bajulus L. and Arobium punctatum Deg. Both are used in tests which define the effectiveness of remedies employed for the protection of timber. Polish technical norms which pertain to the examination of impregnants foresee only the use of larvae of Hylotrupes bajulus L. while norms observed in the European Community include also larvae of the deathwatch. Such efficiency research was carried out in Poland up to 1986 by prof. dr hab. J. Dominik, and subsequently continued by one of co-authors. Investigations into physical methods of exterminating insects are not discussed in Polish norms. The most frequently employed method is a simple chemical operation (spraying, short baths, lubrication). At present, our market offers two Polish products as well as several from Western Europe, chiefly Germany. The establishment of a center which would conduct current effectiveness tests of such products, particularly by taking into consideration the research norms of the European Community appears to be an extremely urgent task. The use of gas for the extermination of insects in wooden monuments is rare. Only two museums in Warsaw have at their disposal their own gas chambers, while a single enterprise can perform such an operation in situ. During his own research, one of the authors found that microwaves are of little use in insect extermination; infrared rays issued by point sources are useless in this particular instance, especially as regards works of art. The method of exterminating insects in architectonic constructions with the application of hot air, konwn for quite some time in Denmark and Germany, has not been tried in Poland. Gamma rays have proved to be highly effective but our publications whose purpose it was to popularize this method have not met with a response, especially in Poland. One of the authors has conducted a number of experiments on the gamma rays not only for the purposes of exterminating insects which damage wood but also those which attack books and fabrics. The outcome of this investigation will be published in the nearest future.