Airflow Error Measurement Due to Pneumotachograph Mask Rim Leaks

A general empirical equation was obtained that relates the leak flow between the mask rim and the face, the size of the leak region, and the amount of the upstream airflow toward the mask: Leak(cm3/s) = 0.33 × Area(cm2) × Flow(cm3/s) for the range of ±2000 cm3/s. This equation may provide researchers and clinicians with a tool for generalizing airflow leak effects.