Test and validation studies performed with UFOTRI and NORMTRI. TW5-TSS/SEP2 - deliverable 4

Several test and validation studies have been performed for the two tritium codes UFOTRI and NORMTRI in the frame of international exercises in particular in the BIOMOVS and the BIOMASS programs, supported by the IAEA. Validation of NORMTRI confirmed that the specific equilibrium approach is appropriate for routine releases as long as yearly averages are of interest. It also strongly depends on the quality of the primary dispersion model except an HT release is of interest. In case of UFOTRI applied for accidental releases, the situation is much more complex and dynamic approaches are mandatory. Testing and validation focused here mainly on the ingestion pathways as it was identified as the most critical pathway in many studies. In particular for crops it could be demonstrated that the generic and physically based approach used in UFOTRI is able to treat the various foodstuffs with sufficient accuracy. (orig.)