A methodology for evaluating nuclear material inventories with respect to their possible use in radiological dispersion devices

A practical methodology is introduced for analyzing and ranking nuclear materials with respect to their possible use in radiological dispersion devises (RDD) and for identifying critical material attributes relevant to terrorist risks, objectives, and consequences under different attack scenarios. The method provides a formal framework for effectively integrating dosimetry and dispersion data within the context of identified terrorist value structures and for quickly analyzing nuclear material inventories regarding their risks and consequences under these value structures, given their particular material properties. The methodology can be readily implemented in software based on a spreadsheet package, for example. The proposed methodology emphasizes on "the value" or utility of material characteristics in achieving terrorist objectives intended to harm human, physical, and military infrastructures. The emphasis given to the value side of the material ranking problem is critical for measuring performance and preference structure rather than material characteristics per se. Certain material attributes may become more relevant than others depending on whether the terrorist objective is to injure personnel, for example, or whether it is to incapacitate large areas in a given military site due to radiological (but not lethal) contamination. Even a single objective case, such as "complicate decontamination efforts," has multiple values associated with it such as human health risks, safety risks, air contamination, or water contamination. In addition, value is a critical notion when there is a need to choose or prioritize actions. In respond to the possibility of dealing with imprecise data, the proposed formal methodology also allows to explicitly incorporate uncertain information and balance judgments about these uncertainties with experts' preferences to possible terrorist outcomes. Insightful ranking decisions can thus be achieved out of conflicting values and multiple objectives.