The influence of sterilisation by gamma radiation on natural durability of wood

Gamma-radiation-induced depolymerisation causes significant changes in wood properties that could influence on wood natural durability. Therefore, Pinus sylvestris sapwood, sterilised by gamma irradiation and steam was exposed to white rot fungus Schizophyllum commune and brown rot fungus Poria placenta. According to EN 113 Cobalt 60Co was used at the dosage of 30 and 150 kGy. Control specimens were steam sterilised. Significant differences in mass loss between gamma irradiated and autoclaved specimens were determined after four weeks of exposure to S.commune. Irradiated specimens lose higher percentage of their masses than non-irradiated ones. During further exposure, differences decreased until they became insignificant. On the other hand, sterilization method doesn’ t have significant influence on specimens’ mass loss after 4 weeks of exposure to P.placenta. However, after 8, 12 and 16 weeks of exposure, irradiated specimens lose higher percentages of their masses than autoclaved ones. With increasing of exposure time, this difference became more and more significant.