Servizio Comunitario di Informazione in materia di Ricerca e Sviluppo - CORDIS

Accident consequence assessment software

COSYMA is a probabilistic accident consequence assessment (ACA) system, which has been developed for use in calculating the risk posed by potential nuclear accidents taking into account the range of conditions which may prevail at the time of the accident. It can be used for deterministic or probabilistic assessments. Deterministic assessments give detailed results for a single set of atmospheric conditions, probabilistic assessments give results taking account of the full range of atmospheric conditions and their respective frequency of occurrence.

The system is designed to run on a personal computer (PC).
The end points of the system are:
air concentration and deposition at particular points;
numbers of people and areas affected by countermeasures;
amounts of food banned;
doses received in selected time periods;
the numbers of early and late fatal and nonfatal health effects;
the economic costs of countermeasures and health effects.

The input is menu driven. The user must provide information on the source term considered, details of the countermeasures strategy adopted, and the end points required. He/she may also change the values of some of the parameters involved in the model. Default values are provided for all parameters. The system includes data libraries for many of the quantities required, such as dose per unit intake or food chain concentrations per unit deposit. Gridded population and agricultural data for the whole of Europe, and a default set of atmospheric conditions, are also provided. Two versions of the system have been made available. One allows users to carry out simple, routine applications using largely default values for model parameters; the other, for more complex applications, offers greater flexibility by enabling model parameter values to be modified to accommodate the needs of the user.

Results are presented on the screen in tabular and graphical form and may also be printed. The system writes a file which the user can input to his/her own spreadsheet if further processing is required.

Reported by

National Radiological Protection Board (NRPB)
OX11 0RQ Didcot
United Kingdom
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