I know it's been covered before about permissions and clearance for field recording -- and the general rule of thumb is to ask forgiveness not permission; be courteous and upfront if approached by people of authority; and leave if and when they ask you to -- but what about areas that there's absolutely no way to simply walk into. Hospitals, military bases, ect.
How do you go about getting permission to record in those areas? Do you have a usual shpeal you tell to their HR / PR / Risk Management departments? Do you have to worry about HIPAA and levels of military clearance?
Any tips or guidance on this would be awesome, as it's something I'll probably be dealing with in the next few months (for work, for a sound-related study in medical simulation, which I'm pretty excited about).