Signs for the blind

One of the things I find intriguing, is how various city and federal regulations combine. One such regulation deals with the signs for rooms in the area where the WycliffeUSA headquarters is located. Several of the WycliffeUSA conference rooms have their name on a plaque above the door. 
It is my guess that there are some ADA compliance requirement that braille be put on the sign as well. But I’ve always wondered how users a braille are going to be able to reach the signs. And know that the signs exist, above the door!