Successful cross‑border co‑ordination during a nuclear emergency requires a common understanding of the outputs of dose projection codes used to guide national decisions on protective actions.
The NEA Expert Group on Comparison and Understanding of Dose Prognosis (EGDP) is currently working on an internal international exercise in which member countries use the same source term for a given accident site, run their own dose prognosis code, and then compare their results with the ultimate objective to improve cross-border co-ordination for calculating radiation dose and risk. In this context, the expert group has developed three drill scenarios considering different source terms and meteorological data: “easy meteorology” (low), “high pressure” (medium) and “frontal passage” (high).
The group met on 28 October 2021 and discussed the results of the second drill, which focused on a complex meteorological situation that involved low winds under high atmospheric pressure with large uncertainties in wind direction.
During this meeting, 20 experts nominated by 11 NEA member countries and one invited expert from Hong Kong, China shared their results and compared respective protective measures with respect to evacuation, iodine prophylaxis, and sheltering. The participants conducted a preliminary analysis and discussed the differences between national approaches, as well as the underlying reasons behind these differences.
The participants also developed the scenario for the third drill, which will involve a frontal passage accompanied by precipitation and resulting changes in wind direction.