A Statistical Analysis of Selected Parameters for Predicting Food Chain Transport and Internal Dose of Radionuclides

摘要

Compliance with environmental radiological standards that limit routine releases from nuclear facilities is usually determined through the use of mathematical models. These are subject to considerable uncertainty. One way of estimating the uncertainty associated with model predictions is through an analysis of the statistical properties of their input parameters. This report presents results of such analyses for parameters incorporated in U.S. Nuclear Regulatory Commission (NRC) Regulatory Guide 1.109. Approximately 200 references are reviewed and the distribution of results are used to estimate the uncertainty in dose prediction resulting from a given concentration of 131I2 in air transported over the pasture-cow-milk pathway. The NRC recommended generic default values are compared with the statistical distribution of the selected parameters, and the probability of the default values not being exceeded is estimated. The results reported herein provide an estimation of actual uncertainties to be expected under real-world conditions in lieu of validation experiments. The relevance of these results is limited because of the qualifying assumption and the quality of data. Methods of taking results from these analyses into account when determining compliance with regulatory statutes are discussed.