There is a device known as a 'Refreshable Braille Display'.
Suppose one of these were combined with a receiver, in one unit, for a blind person to carry in the hand.
It would pick up broadcasts from transmitters located throughout a building, broadcasting what floor they are located on, and whether it is the north-east-south-west end.
The receiver picks up the radio broadcast, and raises or lowers pins on the handheld Braille mechanism, to display the floor number, etc.
A refreshable Braille display is expensive at this time. The link above proposes a technology which is less expensive.