"Fly heading two three zero, runway two seven left, cleared for takeoff." Air traffic controllers are among the 25 to 45 percent of the workforce in the United States who use their voices professionally. It is imperative for their listeners to understand what they are communicating. Air traffic controllers, teachers and university professors have a high prevalence of voice disorders referred to as "dysphonia." Other professions also are at risk including clergy, attorneys, counselors and performers.
* This article was originally published here
