Many (or most) vision, hearing and speech impairments would likely be disqualifying for ATC; if they were to the point of needing accomidation during an interview. Mobility impairments would likely be able to be reasonably accomidated though; someone without use of their legs could work in an ATC facility that can be accessed without stairs, which would exclude some towers but not all of them. The workstation height may need to be adjustable as well, but that's not an unreasonable accomidation either.