The Nuclear Energy Agency has made significant progress to strengthen member countries’ nuclear and radiological emergency preparedness and response, more specifically in their ability to co-ordinate and harmonise their respective protective actions. One area that has been targeted is greater harmonisation and cross-border co-ordination in dose prognosis, which is a key tool used to inform decisions on the implementation of protective actions.
The Expert Group on comparison and understanding of Dose Prognosis (EGDP) held its 7th meeting on 5-6 October 2022 at the NEA offices to compare and analyse the results of a series of drills conducted in 2021 by 11 member countries. During the exercises, member countries used their respective national approaches and tools for dose prognosis and consequences management to consider different source-terms and meteorological conditions, including:
- “Easy meteorology” scenario (low) - assumed steady wind and plume directions;
- “High pressure meteorology” scenario (medium) - assumed low wind speeds and large uncertainties in wind directions;
- “Frontal passage” scenario (high) - assumed precipitation and changes in wind directions.
The EGDP identified commonalities and differences between countries, and highlighted how certain criteria, such as source term estimates, have a significant bearing on the results. These outputs will also be used to identify ways to fill gaps, for example, by sharing data and recommending more joint exercises.
In order to harmonise cross-border decisions on protective actions, the EGDP will present a reference guide for member countries to collaboratively improve cross-border co-ordination through a common understanding of the factors that influence dose projection codes and lead to different outputs. The recommendations will be issued in 2023.