I would like to ask, if Braile signs are a must for all type or interior wayfinding and room and area identification sigange in public and private buildings.

I'm so sorry I didn't see this when it was posted! In case this person is still checking, no and yes. Braille signs are required to identify rooms and spaces, including exit doors and restroom doors. Also included are floor levels within stairwells and on elevator panels. However, other wayfinding signs such as directional and informational signs do not have to have braille. They do have to be highly readable, however, with high contrst, no glare, and easy to read typefaces.

Sharon Toji