Generally no, not if employees are able to communicate by using pen and notepad and it is effective.  However, in situations where the exchange of information is over a long duration or the information being exchanged is complex it may be necessary for the business to provide a qualified interpreter. A business should discuss with the person with the disability to determine which auxiliary aid or service will result in effective communication.

For additional information, take a look at the following resources:

FAQ: What kinds of auxiliary aids and services are required by the ADA to ensure effective communication with individuals with hearing or vision impairments? [2]

Fact Sheet: Effective Communication [3]