| abstract |
A method of calibrating the output of a transducer in a flow path through which a medication is delivered from a hand-held metered dose inhaler is disclosed. The transducer senses flow rates of human breath during inhalation and exhalation through a portion of a flow path in the inhaler. The flow rates have two non-linear flow characteristics in opposite directions. The flow path portion provides flow rate measurements representative of flow paths of the entire system. The method makes it possible to precisely calibrate so that precise doses of medication can be repeatedly delivered to a patient by inhalation. |