Radiological Contamination

DOE-HDBK-6004-99

Radiological Contamination

Radiological contamination concerns include tritium and activated dust from plasma facing

components. The tritium contamination is primarily a personnel protection concern that effects the

design of systems or modules and is not a direct threat to equipment. However, any high stress

components that see a significant tritium environment must be monitored for hydrogen embrittlement.

The direct contamination of equipment from other radiological materials is a potential. Equipment

design should allow for rapid decontamination and maintenance to ensure operability and minimize

personnel exposure potential.

Magnetic Fields

The magnetic fields associated with the fusion facility magnets is very large. A constant magnetic

field will be present near the torus and extremely large transient fields occur during plasma

disturbances.

The electrical interference caused by the above field transients should not cause critical electronic

failures or unexpected responses from remote handling equipment. A significant level of

electromagnetic interference is expected due to routine magnet cycling. The remote equipment must

be able to accommodate this interference without damage.

Radio Frequency Fields

High radio frequency (RF) fields are normally present near the torus. Remote handling equipment

in this vicinity should be able to accommodate the resultant interference as a normal occurrence.

Hydrogen Isotopes

Hydrogen generation is a potential result of plasma excursions or excursions of other process

materials into the plasma, during off normal excursions. Tritium and deuterium are also potentially

present during off normal events.

All of the hydrogen isotopes are equally flammable, and when present near the remote handling

equipment present an equipment and personnel hazard. The oxidized state of tritium is a particular

personnel hazard.

Materials Of Construction

Material Considerations

The acceptable materials of construction for equipment in the vicinity of the fusion facility are

affected by the hazards unique to a fusion facility. Major areas of concern are the activation of

materials by the intense neutron bombardment, the degradation of materials by all forms of radiation,

and the contamination of surfaces from the transfer of radiological materials.