A review of dust in fusion devices: Implications for safety and operational performance

Dust is produced in fusion devices by energetic plasma–surface interactions. As the amount of dust increases, potential safety and operational concerns arise. The dust may contain tritium, may be radioactive from activation products, and may be chemically reactive and/or toxic. Possible accidents in large fusion reactors could mobilize the dust and threaten public safety. Dust also poses potential problems to device operation. For example, plasma startup could be impeded, particulate injected from flaking deposits may disrupt the fusion plasma, and tritium retention in dust will affect fuel recovery systems. The current understanding of dustʹs role in fusion devices is reviewed in this paper by discussing mechanisms of dust production, considering ways dust impacts device safety and operation, and comparing characteristics of dust collected from existing fusion plasma research devices.