[en] Notably based on the return on experience of the Fukushima accident, measures of protection of population and distribution of medical countermeasures have been evolving. This publication aimed at proposing recommendations for the evolution of the health arrangement, more particularly for populations concerned by iodine intake. After a recall of contextual aspects (definition of the nuclear risk, issue of release of radioactive products, strategy of protection, campaigns of steady iodine pill distribution, national and local involved actors in case of nuclear accident), the report proposes an overview of health risks and of the prophylactic action related to releases of radioactive iodine (occurrence of thyroid cancers, prophylactic treatment with potassium iodide, concerned populations and associated dosage). It also discusses the risk perception (from a general point of view, and with respect to the nuclear risk) and behaviours. It describes crisis training exercises or simulation as elements of risk management plans (general principles, training regarding situations of nuclear accidents). Then, based on hearings, bibliographical data and discussions, the report discusses the intake of steady iodine for the different age ranges and for some specific populations (pregnant women, thyroid pathologies, disadvantaged populations), the available treatments based on potassium iodide, the organisation of the distribution of potassium iodide pills (national campaigns, other possible organisations, concerned health professionals, existing organisation within educational institutions), issues related to risk perception and to behaviours (available information, efficiency of distribution campaigns, emergency exercises). Recommendations are then stated regarding the different populations, available treatments, pill distribution organisation, risk perception and behaviours