Monte Carlo simulation for the evaluation of measurement uncertainty of spent fuel analytical results

The present paper describes an approach based on Monte Carlo simulation for the evaluation of uncertainty of nuclear spent fuel analysis. The mathematical model of measurement was established by examining the dissolution process step by step. The results are consistent with those obtained by the classical propagation of variance approach. This paper shows the importance of taking the process into account in order to give a more reliable uncertainty assessment to the result of a concentration ratio of two isotopes in spent fuel. Indeed, for some radionuclides, the uncertainty associated with the upstream steps of the analysis (“process” uncertainty) can represent up to 95 % of the overall uncertainty.