In the near future humanity discovers a spatial anomaly at a point located somewhere between the orbits of mars and earth. This anomaly quickly induces delirium in anybody who approaches it and even seems to have mild (though sometimes severe) reality warping effects on its environs. Notwithstanding all this, (being the curious naive idiots that we are) humans attempt to study what is dubbed "The Strangeness", at first via probe, but eventually with full blown manned-missions. Naturally, these all end terribly (lots of dead/insane astronauts).
The good thing that came out from the horrors of the latter, is lots of data! Using what the various astronaut teams were able to collect and transmit before their demise, scientists on Earth manage to invent "meta-memetics containment fields", which can be used to isolate/contain the madness leaking out from The Strangeness. Rudimentary versions of such - which shield from some, but not all of the anomaly's corruption - can be implemented into small systems such as spacesuits. This considerably improves the research progress speed by subsequent teams and soon an entire space station is build around The Strangeness and extensive experimentation begins.
The space station is a rotating torus with the anomaly located in the donut hole in the center. It generates two very large advanced MC Fields - these ones perfected: they block all the effects of The Strangeness from escaping, or atleast in theory... - in the form of two transparent force spheres, one inside the other. One seperates the donut hole along with the spatial anomaly from the space station, the other is located outside the space station and thus seperates the anomaly and the space station from the rest of space.
Now my question is why would these containment systems be arranged in this way?
It makes sense to have two containment units, of course, redundancy is imperative in any engineering project (especially those related to eldritch abominations), but why would one sphere be outside the space station? Why not setup both spheres to be between the anomaly and the space station?
Now in my story there are very good (read evil) secret reasons why this needs to be the case, but are there any proper engineering explanations for why a redundant containment system would essentially "trap" people on the inside of what you're trying to contain, in the event of a primary failure?
This question is a follow up to this one.