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Particles with sizes ranging from 100 nm to 100 μm are produced in tokamaks by the interaction of the plasma with the first wall materials and divertor. Dust has not yet been of a major concern in existing tokamaks mainly because their quantities are small and these devices are not nuclear facilities. However, in ITER and in future reactors, they could represent operational and potential safety issues. The aim of this paper is thus to describe the dust creation processes in the tokamak environment. The diagnostics and removal techniques that are needed to be implemented to measure and minimise the dust inventory are also presented. The integration of these techniques into a tokamak environment is also discussed. [ABSTRACT FROM AUTHOR]

During ITER lifetime, dusts and flakes will be produced due to the interaction of plasmas with the in-vessel materials or due to maintenance. They will be made of carbon, beryllium and tungsten and will be activated, tritiated and chemically reactive and toxic. Safety limits have been set in order to reduce dust hazards. Thus dust diagnostics and removal methods need to be developed for ITER within the constraints linked to magnetic field, radiation, vacuum and temperature. This paper reviews potential diagnostics to monitor the dust content using techniques already used for erosion or deposition monitoring or techniques specially developed for measuring dust in suspension. [ABSTRACT FROM AUTHOR]