ConvEx-3 are organized by the IAEA every three to five years and are largescale joint international exercises that take place during the early phase of a severe nuclear or radiological emergency in a Member State.

These exercises are designed to evaluate the response to a major nuclear or radiological accident, with a focus on the exchange of information, assessment and prognosis processes, provision of international assistance, coordination of public information, and inter-agency response. They serve as an important opportunity to identify deficiencies in both national and international emergency preparedness and response arrangements that could hinder effective response measures aimed at minimizing the consequences of an emergency.

The overarching objectives of the ConvEx-3 exercise are to enable States and relevant international organizations to test their responses to severe nuclear emergencies at nuclear power plants, which could result from accidents, natural disasters, negligence, or security events. The exercise also aims to evaluate the international emergency management system and identify good practices, as well as pinpoint weaknesses and areas needing improvement that might not be otherwise recognized.