On June 25, the World Health Organization (WHO) wrapped up its role in a 36-hour nuclear emergency drill, organized by the International Atomic Energy Agency (IAEA).

This simulation was part of the IAEA’s ConvEx-3, its most advanced level of emergency preparedness exercises. Held every three to five years, ConvEx-3 evaluates the readiness of international responses to nuclear incidents and highlights opportunities for improvement. The previous drill in this series took place in 2021, in collaboration with the United Arab Emirates.

This year's exercise engaged over 75 nations and 10 global agencies. It focused on a fictitious emergency at a nuclear facility in Romania that led to the widespread release of radioactive material. Participants exchanged real-time updates, evaluated the potential hazards, coordinated their actions, and determined appropriate safety and medical measures.

To support the exercise, WHO activated an Incident Management Support Team with personnel from its national offices, regional hubs, and central headquarters. This team collaborated with country authorities to track health impacts, produce public health messages on protective measures, and provide psychological support strategies for both affected populations and frontline workers.

New components in this year's scenario included joint protective actions from bordering nations such as Bulgaria and the Republic of Moldova, the staging of international aid missions, and the added complexity of cybersecurity challenges. A more advanced social media simulation tool was also employed to put communication plans to the test.

By re-creating complex nuclear emergencies that cross borders, these drills reinforce international systems, validate technical preparedness, and enhance collective response strategies. WHO remains committed to global radiation safety through continuous support to member countries by offering research-backed guidance, tools, and advice on health risks related to both ionizing and non-ionizing radiation.

After the event, the IAEA will release a comprehensive review detailing effective practices and suggestions for refinement. WHO will study these outcomes to refine and strengthen its emergency procedures.