Nuclear Accidents

4Management of the Emergency Phase of a Nuclear Accident

4.1. Introduction

All nuclear installations must take strong preventive actions to ensure the best possible reactivity in the event of an accident. The prevention phase must consider in detail how to manage the nuclear facility so that it continues to operate as normally as possible. It is also important to ensure that its personnel are efficient and responsive to any deviations from normal procedure in the installation. This phase is also the time when actions to limit radioactive releases in the event of an accident must be considered, as well as solutions to limit radioactive deposits in the soil (Figure 4.1).

After the accident, the situation is divided into two main phases, the emergency phase and the post-accident phase. The first phase is acute and lasts a short time. The second phase, on the other hand, is very long. The emergency phase itself consists of three periods: a first period, known as the threat phase, when the accident is foreseeable; a second period when the accident occurs with radioactive releases into the environment; and a third period that marks the end of the state of emergency. The post-accident phase consists of two stages: a transition period and a long-term period.

Often, during the management of the accident, rules are flouted and errors of assessment are made. During the crisis, the political authorities must simultaneously take on eight tasks:

1. i) ensure the evacuation of populations; ...