If faculty are behind plexiglass, are they required to wear masks?

We want everyone to be as protected as possible, so instructors are encouraged to wear a face mask when standing behind a plexiglass shield for multiple layers of protection. If an instructor feels as though their teaching abilities will be hindered while wearing a face mask, they can opt to wear a face shield instead. If the instructor moves away from the plexiglass shield, they must wear a mask under the face shield.