[en] Potential radiological hazards to plant personnel and the public associated with a severe accident in a nuclear fusion reactor must be assessed. A technique to determine the constraints on severe accidents in lithium-cooled fusion reactors is developed. The method uses a probabilistic approach to risk calculation. Volatilization of structure as a result of lithium fires is the most effective mechanism for activation product release. Factors that influence the consequences of lithium fires are identified. The consequences of a severe accident in a properly designed fusion reactor are substantially less than those of an LWR accident