UPDATE: Per a conversation with Technical Assistance at the US Access Board, it was clarified that employee only work areas are not required to have turning space. Turning space is only required in those areas where it is specifically mentioned in the ADA Standards. However, while in Texas, use the interpretation below.
I can’t believe that I have waited this long to write this post considering that this question is asked at least once a week.
The Texas Accessibility Standards, and similarly the ADAAG, requires that most areas be designed so that a person in a wheelchair could enter and leave the space. For employee work areas, this is the only requirement:
4.1.1 Application. (3) Areas Used Only by Employees as Work Areas. Areas that are used only as work areas shall be designed and constructed so that individuals with disabilities can approach, enter, and exit the areas. These standards do not require that any areas used only as work areas be constructed to permit maneuvering within the work area or be constructed or equipped (i.e., with racks or shelves) to be accessible.
Even a Janitor’s Closet must meet the requirement for approach, entry and exit. This may require a 60″ diameter turning space (or T-turn, see 4.2.3). The big concern is that a person could become trapped within a small space if the door were to close behind the wheelchair and a 180 degree turn was not possible. However, if the space is so small that a wheelchair (presumably occupying a rectangular space that is 30″ by 48″) cannot maneuver beyond the swing of the door, a turning space is not required.
Electrical, mechanical or IT closets are exempt from this requirement, but if a closet serves dual purpose Janitor/Mechanical, access is required.