Oh, the Mines... Thanks for taking the time to let me know, but that doesn't count--hostiles are allowed to spawn within view in non-standard branch maps, e.g. the Mines (and, rarely, Waste, and in the future the Caves and possibly a couple other places).
Sorry I forgot to mention that. I believe it's been mentioned in another thread where this topic came up, and I thought I'd said it here...
Where it definitely should never happen is in the main complex (or Storage).