In the city where I work, commercial buildings over a certain size must have designated restrooms for both men and women.
One company that I conduct business with recently remodeled a large warehouse for their offices. They included several "single-holer" unisex restrooms (with locks on the doors) in the plan.
In order to pass final inspection and receive an occupancy permit, they had masking tape on the doors with "MEN" and "WOMEN" written in magic marker.
The inspector signed it off since it complied with the letter of the law. The masking tape was removed shortly thereafter.