I've worked with 21T magnets (NMR), the head just in the unshielded parts of it (you cant really get your head inside these as the bore size is small but you are right where the field lines start to bend). Never noticed anything. Colleagues working on larger bore but lower field magnets told me that moving their head fast around them was making them feel weird.
Back in the day I spent the best part of three years working with NMR machines pretty much on a daily basis, also never noticed any physical effects.
Once I almost had a magnet snatch my bunch of lab keys out of my hand, having forgotten the cardinal rule to "leave all magnetic materials at the desk before you approach the magnet with your sample tube"...
Heard a joke about the children of NMR staffers having atypical sex ratio, but that was just student humour. I think :)
