An experimental study on natural weathering of radionuclides from urban surfaces for aerosols deposited in wet and dry conditions

The European Model for Inhabited Areas (ERMIN) predicts long-term doses and other consequences following contamination of built-up areas by airborne radioactivity. Central to ERMIN are empirical models of the long-term behaviour of radionuclides on building and other surfaces in the environment. Experiments in which building materials were contaminated, and weathered outdoors for up to 1 year following contamination have enhanced the data on weathering from surfaces that can be used in ERMIN. New data have been obtained for the elements americium, cadmium, caesium, cobalt, iodine, ruthenium and strontium and for the surfaces brick, concrete and clay roof tiles, concrete slabs, glass, sandstone, tarmac and wood cladding. The results have highlighted some differences between the retention of aerosols on surfaces, particularly for glass. This paper presents a summary of the results and identifies the main differences in retention observed.