This report (HPA-RPD-009) describes SECTAR (statistical estimation and characterisation techniques for use during accident response).
The SECTAR project investigated the potential of statistical techniques to improve estimates of the extent of radioactive contamination in the early stages of an accident. Two major categories of techniques, geostatistics and Bayesian methods, were investigated and applied to measurement data from nuclear accidents at Tomsk, Chernobyl and Windscale. Trials were carried out using the statistical techniques alone and in conjunction with the traditional assessment methods of atmospheric dispersion and foodchain modelling.
Results from this process of ‘data assimilation’, the combined use of measurements and modelling to make estimates, indicated that several of the methods tested had the potential to be useful to the Food Standards Agency. In particular they would help in the quick and reliable estimation of food restriction areas and in determining areas where sampling effort should be concentrated.