I actually used to carry all the time in a research facility where we had a 16.4 Tesla NMR machine we used to do MRIs on rodents. No problems. Just don't stand inside the red line while it's running....
that said, the field was also tiny (maybe the the size of a can of tennis balls).
I don't carry into healthcare facilities when I am working there because of the professional hazards, not so much the magnetic kinds...