Neutron Shielding

Material layers that slow and absorb fusion neutrons to protect magnets and people.

Shielding between the plasma and the magnets (and the outside world) slows and captures neutrons, protecting the superconductors from damage and staff from dose. It is heaviest on the neutron-rich breeder.

Shielding between the plasma and the magnets slows and captures neutrons to protect the superconductors' lifetime, and it is heaviest on the neutron-rich breeder where space in the central column is scarce. Achieving adequate magnet protection in a compact machine is a genuine neutronics constraint, not a formality.