David Chang, EdD, RRT-NPS, is a professor of the Department of Cardiorespiratory Care at the University of South Alabama, in Mobile. He has served on many committees and in many capacities at the American Association for Respiratory Care (AARC), National Board for Respiratory Care, and Commission on Accreditation for Respiratory Care. Dr. Chang’s special interest is in research and mechanical ventilation. He has published five textbooks and developed an open source website, rtexam.com, for students and practitioners. In his spare time, Dr. Chang conducts training sessions for students and educators at the state, national, and international levels.