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Uncertainities in assessments of terrestrial foodchain doses: sources and implications. - RP0141

i)To identify the sources of uncertainty in terrestrial foodchain dose assessments. ii)To review the techniques available for estimating the extent and significance of these sources. iii)To review the available data on uncertainty ranges on dose assessment parameters, in particular the parameters in atmospheric dispersion and deposition modelling, foodchain transfer models, dosimetric modelling. The uncertainty associated with data on intakes will be considered, through the results of a recent MAFF funded project. This study will be undertaken for the principal food categories and for the key radionuclides of I-131, Sr-90, Cs- 137 and Pu-239. iv)The dose assessment models currently used by MAFF to predict doses from short and long duration releases of radioactivity through the foodchain will be studies, to ensure that the conclusions of the study on the sources and extents of uncertainties in food dose calculations are applicable to the assessments undertaken by MAFF. Any specific features of the MAFF models which have implications for uncertainty will be highlighted. v)Techniqes for presenting the uncertainty in dose assessment results will be reviewed, and preferred options for this will be recommended. vi)The implications of these uncertainties for MAFF dose applications will be studied. In particular, the implications of uncertainty in dose calculations for regulatory purposes, including the possibility of predefining the accuracy range of a best estimate dose assessment, and the role of such a range on the best estimate of dose in the regulatory system, will be considered. vii)A contract report will be finalised.
Time-Scale and Cost
From: 1995

To: 1997

Cost: £140,000
Contractor / Funded Organisations
National Radiological Protection Board