Abstract: An airflow sensor (thermal sensor assembly) that is designed to adhesively attach to different styles of a cannula and that can detect the movement of respiratory air through the nasal and/or oral cavities. When secured to the cannula, the airflow sensor has its nasal and oral sensing elements in positions that will maximize signal accuracy, minimize airflow signal artifacts, and minimize occurrences of signal loss due to direct patient skin contact. The airflow sensor does not disturb the flow of air from the patient or add any discomfort to the patient. The airflow sensor can be attached to most nasal or nasal/oral cannulae used in sleep disorder diagnostics.