Device and method for estimation of pulmonary function characteristics

A device for determining at least one pulmonary function characteristic, the device comprising

• (i) at least one chamber comprising
• at least one gas inlet port, configured to receive gas flow;
• a distal element comprising at least one distal opening;
• at least one pressure transducer configured to detect pressure within the at least one chamber and to produce a signal upon detecting pressure at about a predetermined threshold;
• (ii) at least one shutter module connected to said distal element, said at least one shutter module comprising at least one shutter opening;
• and
• (iii) an actuator configured to displace, or induce displacement, of the at least one shutter module upon receiving the signal, or a signal derived from said signal,
• wherein the at least one shutter opening is configured to allow passage of gas flow from the at least one distal opening to the atmosphere through a first total effective area enclosed by a perimeter of the at least one shutter opening, when the shutter module is in a state of first end position;
• and
• wherein upon said displacement the first total effective area changes to a second total effective area, when the shutter module is in second end position.