Novel concept of neutron shield for ITER diagnostic Lower Port Integration

•Radiation shielding engineering in vacuum vessel for fusion reactor.•Port integration engineering knowledge.•Feasibility to use powder of boron carbide as neutron shielding material. Neutron shield for ITER Diagnostic Lower Port Integration in Vacuum Vessel consists of Diagnostic Rack that put tenant’s diagnostic on it and Backplates. This paper proposes a novel concept of Neutron shield that uses Boron carbide powder canned in a stainless-steel box. A prototype was made to demonstrate the novel concept of Neutron shield, and it confirmed the density of B4C for the prototyping reached 1915 kg/m3, 76 % of the actual density of 2520 kg/m3. Neutronics was performed by applying the density confirmed by the prototyping. As a result, 45 μSv/h of Shut Down Dose Rate (SDDR) was achieved and satisfied its target. And additionally, 9.35 ton of neutron shield weight satisfied its target.