Same events as this question. Kit is ordered to let a task-force handle a possible sabotage of the stations fusion power plant. She ignores them and vents the core plasma out into space to keep the reactor from reducing the lower levels to radioactive slag, herself included.
This is entry 1.5 out of 3 set in the same place, a laboratory on the moon of a gas giant in the alien star system Ilus. If you'd like context as to the story, look up there.
Armed with a marginally better understanding of how fusion reactors work, as I can understand, you'd probably be better off using some kind of pulsed tokamak style reactor. The fusion cycle would burn D-He3 in an a-neutronic wave, momentarily increasing the pressure of the plasma torus, then letting the reaction expand against the containment field and the Lorenz force generate energy, which is used in the next cycle.
The reactor would be reminiscent of a stellarator, which has a preset geometry which the plasma torus rotates within, keeping it stable, and the plasma torus would stay at near-critical condition and sinusoid between fusion and generation, similar to general fusion's ram-and-spinning-ball-o-lead reactor, but hybridized with a stellarator.
I don't discuss it much in the book, because as atomic rockets puts it simply, if someone asks you how your drive works, you tell them it works just fine. A non-answer.
The question is wether a reactor working on the tokamak principles be able to blow itself up. There is one critical piece of information here, which is that it runs on the D-He3 cycle, and not the D-T neuronic cycle, which puts off deadly neutron radiation.
For one, the D-T cycle puts off a lot more energy at a given plasma pressure and temperature, but as deadly radiation that can only be used to make heat, a lot of heat. Around 50X more energy at a given ignition state. The reactor would not be shielded to handle a purely neutronic reaction, and if tritium is injected into the plasma and let fuse, it will irradiate and slag the entire engineering wing.
But would the plan of injecting way-more-volatile fuel into the core and let it fuse slag the place? I don't expect a show of sparks per-se, but of finding the entire engineering wing full of dying technicians, horribly burned and in pools of their dissolving skin, blood and uniforms... well if Kituki had listened to her superiors, at any rate. (Well... that got nasty.)