A large number of accident sequences have been analysed in ITER, and this has led to the identification of limiting cases which envelope the worst case scenarios. These limiting cases, when combined with the most damaging weather conditions, lead to estimates of the amount of radioactivity that can be dispersed outside the plant under the worst cases. Assuming no evacuation, this then leads to estimates of the dose received by members of the surrounding population.

These analyses show that under normal operation the extra annual dose to the most exposed individual is about 1% more than that of natural background radiation. Under the worst case accident scenario, the extra annual dose the most exposed individual would receive is about double that of natural radiation (which itself varies by more than this factor from place to place). Even under the worst accumulation of accidents (for which no chain of events can be envisaged), evacuation of the most exposed individual would not be required according to ICRP and IAEA guidelines.