Design and simulation of a counter measure analysis system in a decision support system ONERS for nuclear emergency

In this work, a Counter Measures Analysis System (CMAS) is developed in the Online Nuclear Emergency Response System (ONERS) to suggest protective actions for minimizing radiation exposure to people during accidental releases of radionuclides to the environment. CMAS is designed with PHP, Java and MySQL database engine in Web-GIS environment to enable online computations and visualization of results. CMAS maps the dispersion model simulated radiological doses to each village unit by spatial aggregation of dose from all the grid cells contained within village unit and delineates the domain into areas assigned with several protective actions taking into account of dose criteria. It also computes residual and averted doses along with timing of different protective actions in each village. The effectiveness of CMAS is tested by simulating the consequences for a hypothetical accident. Results suggest that CMAS provides realistic estimates of protective actions following the spatial dispersion and dose pattern at each village unit. Comparison with conventional grid-based calculations indicate CMAS provides more practical suggestion of protection strategy compared to grid-based suggestions due to the conservative nature of estimates and attribution of all necessary information for emergency management. Sensitivity tests with respect to accident source term and dose criteria indicate that CMAS produces corresponding variation in impacted areas and protective actions confirming consistent performance.