As a result of the Commissariat à I’Energie Atomique CRAC experimental program, which studied the phenomenology and the radiological consequences of a criticality excursion in fissile solution, the EDAC system has been developed. This system detects a criticality accident and warns personnel as early as possible by triggering the necessary audiovisual alarm. The main features of this equipment are its ability to cover all types of accidental kinetics and to use sensors giving a total dose response in neutron and gamma radiation. According to new results acquired with the SILENE reactor in the field of criticality accidents, an evolution is taking place in France. An improved EDAC system is being designed not only to trigger a criticality alarm but also to provide information on the accident, to assist in accident diagnosis, and to contribute to being better equipped to cope with an accident situation, for example, if intervention is needed or if reoccupation of evacuated areas is desired.