Accidental Tritium Doses Based on Realistic Modelling

An early effective dose equivalent (EDE) to the most exposed individual of the public (MEI) at 1 km of 0.5 mSv per g tritium released in HTO form is presently used to quantify the environmental impact of accidental tritium releases from future fusion devices like NET (Next European Torus) or ITER (International Thermonuclear Experimental Reactor). To quantify the uncertainty margin of this value, the computer code UFOTRI, that accounts for the complex behaviour of tritium deposition on plants and soil, and the subsequent re-emission of HTO to the atmosphere, was used for parametric studies. Typical realistic “worst case releases” based on recorded meteorological weather sequences have been identified and analysed. Individual and collective doses due to inhalation, skin absorption and ingestion have been calculated.