AbstractThe radiological hazards associated with the operation and maintenance of fusion machines are cause for safety and regulatory concerns. Current experience in the nuclear industry, and at operating tokamaks confirm that a high level of occupational safety can be achieved through an effective planning process. For fusion facilities with increased hazard levels resulting from the introduction of large quantities of tritium, and higher neutron flux and fluence, a process must be implemented during the design phase to address both the worker safety and the regulatory requirements. Such a process has been developed and was used for the radiological occupational safety assessment of the International Thermonuclear Experimental Reactor (ITER). The purpose of this paper is to describe the approach used, including, the implementation of the as low as reasonably achievable (ALARA) principle for individual and collective doses in an evolving design, and the demonstration of adequate radiological occupational safety during the design process.