Work in this area is often very expensive to conduct, and so has often been performed on a collaborative basis between groups of countries, usually under the aegis of the Organisation for Economic Co-operation and Development's Committee on the Safety of Nuclear Installations (CSNI).
Due to the high cost associated with research in this area, collaborative efforts have been common, involving multiple nations working together, often under the oversight of the OECD's Committee on the Safety of Nuclear Installations (CSNI).