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When artefacts of traditional cultural heritage are waterlogged due to floods and other disasters, they can be quickly protected from contamination by harmful fungi using irradiation treatments. In this study, we showed that Epicoccum nigrum has the potential to contaminate traditional heritage artefacts made of Korean paper and silk under waterlogged conditions. E. nigrum showed 60% lower mycelial growth in medium containing freshwater than in medium containing natural seawater. Control of this contamination was attempted using gamma and electron beam irradiation disinfection technology. The mycelial growth of E. nigrum irradiated with a 5 kGy dose of gamma rays was completely controlled at 15 kGy dose. Next, we evaluated the effect of irradiation on contaminated sample artefacts. E. nigrum growing on waterlogged sample artefacts of cultural heritage was completely controlled at 15 kGy in freshwater-immersed artefacts of Korean paper and silk and seawater-immersed silk. However, in Korean paper immersed in seawater, 15 kGy gamma-irradiation treatment did not control growth of the fungus. Our results suggest that at least 15 kGy of gamma radiation should be used to for treatment, to preserve waterlogged traditional cultural heritage artefacts of Korea, after flooding or other disasters involving water. • Epicoccum nigrum is a radiation-resistant contaminant of historical artefacts. • E. nigrum contamination occurs during fresh- or sea-waterlogging. • Treatment with 15 kGy GI or EBI completely controlled E. nigrum. • Irradiation control of E. nigrum may be dependent on sample composition. • GI and EBI are viable decontamination options against fungal attack. [ABSTRACT FROM AUTHOR]

Abstract: The saturation of South Korea''s at-reactor (AR) spent fuel storage pools has created a need for additional spent fuel storage capacity. The Korea Hydro & Nuclear Power Company is planning to construct a MACSTOR-400 facility composed of reinforced concrete. In concrete structures, cracks occur due to thermal stress, hydration heat, weather, load and other reasons, and shielding performance changes according to the event by crack. However, there are no researches providing the allowable crack for shielding. This paper presents estimating the effect of concrete spalling on gamma-ray shielding performance in MACSTOR-400 based on an FEM simulation. When the cover thickness is under 10cm, it is estimated that spalling will be formed. Generally, because cover thickness is under 10cm in the concrete structure, it is estimated that spalling will be formed in MACSTOR-400. If the thickness of wall in MACSTOR-400 is over 100cm, it is estimated that surface dose rate will be maintained within the radiation safety standards under any conditions related to crack effect. The results of this study may be used for developing standards for radiological safety in shielding structures, especially in relation to the shielding margin. [Copyright &y& Elsevier]