I know in general there's some things about humidity, air quality, and air flow, but outside of that I don't know much.

Effectively though, it needs to follow all the rules of a regular house, including a "means of escape"

Usually you can go to your city town hall and inquire about the local codes. They can be different state to state, city to city. The main thing is going to be an escape root for emergencies, but other than that things like air flow, window requirements and what not can be different for each place.