Who is doing the scheduling of the interpreters? One person at the company should be doing all the scheduling so that it is coordinated. Usually it's someone in the HR department.
If you and your supervisors, and the other employee and her supervisors can agree to using one person to coordinate all interpreting scheduling, then that should reduce the conflicts.
The company should be responsible for the scheduling and hiring of terps. The Deaf employees shouldn't have to be burdened with that task. If you and your supervisors let the HR rep (or whomever) know your needs in a timely manner, then it's up to that person to resolve any scheduling conflicts. The Deaf employees shouldn't be making any direct contacts with the terps. The terp should report to the HR rep, and then follow the rep's orders as to the assignment.
This is the best arrangement for companies that have more than one deaf employee.
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