From radiology to a world-in-crisis: Rolf Sievert and the re-orientation of the International Commission on Radiation Protection in the post-war period

With this paper, I suggest focusing on <i>diplo-scientific actors</i> as a fruitful approach to study how certain actors have helped to shape international organisations through their diplomatic activities and scientific practices. Using the example of the Swedish medical physicist Rolf Sievert, I show how Sievert's personality and preferences came to decisively shape the post-war trajectory of the International Commission on Radiation Protection (ICRP) and more broadly the international landscape of radiation protection. In the inter-war period, Sievert was engaged in the ICRP and its mother organisation, the International Radiological Congress (IRC), dealing with the interwoven questions of how to formulate international radiation standards and radiation protection initiatives. Following the Second World War, Sievert became concerned with the proliferation of nuclear technologies and the spread of radioactive fallout following nuclear test bombings. Because of this concern, Sievert set out to separate the ICRP from the IRC and form a new, independent group that could deal with the dangers of the new 'Nuclear Age'. While Sievert was ultimately unsuccessful, his attempts would decisively change the purview and trajectory of the ICRP. This had large ramifications, as the ICRP continues to be the prime international organisation on radiological and medical radiation protection, formulating recommendations that are used by international, regional, national, and local groups, informing epistemic judgements on radiation research.