I do wonder what "inherently safe" means. I doubt that any form of power generation is inherently safe. While less of a problem that with fission, fusion does produce radioactive waste. Even aneutronic fusion (which is further from our reach) produces radioactive waste via side reactions and gamma excitation (an excited state of an atom may decay to a radioactive isotope by beta emission rather than back to the ground state via gamma emission). Perhaps they mean that runaway power excursions (leading to meltdown, etc.) don't occur; in that case the term also to some fission power designs.