COSYMA: a computer system for the probabilistic assessment of consequences from hypothetical accidental releases of radioactive material

The paper gives a description of the computer program system COSYMA (Code System from MARIA) developed by the National Radiological Protection Board (NRPB) in the United Kingdom and Forschungszentrum Karlsruhe (FZK) in Germany as part of the European Communities MARIA (Methods for Assessing the Radiological Impact of Accidents) project. COSYMA is provided as a flexible package designed for use in probabilistic accident consequence assessment (ACA). Versions for use on PC and mainframe computers are available, and are distributed on behalf of the European Commission. ACA is used to study the potential risks from hypothetical accidents at nuclear plants. It provides an input into emergency planning, siting, and design studies. ACA codes are generally used to calculate the probability distribution of the consequences allowing for the different conditions which might occurred at the time of the release. The paper describes the structure of PC COSYMA, the pathways of exposure considered and the end points of the calculation. (Author) 1 Fig., 6 Refs