Which device is calibrated using a super syringe?

• A. Pneumotachometer
• B. Spirometer
• C. Plethysmograph
• D. Kympograph

Answer: (B)

Calibration of a spirometer relies on a precision volume source to verify accuracy. A large volume syringe, often called a three-liter or “super” syringe, is attached to the spirometer mouthpiece and used to inject or withdraw known volumes. By delivering precise volumes across the device’s measurement range, you check that the spirometer’s readings match the actual volumes and that the response is linear and accurate for both small and large breaths. This ensures that spirometric results such as tidal volume, vital capacity, and peak flow are trustworthy.

Pneumotachometers and plethysmographs involve different calibration principles: pneumotachographs are typically checked for flow and pressure relationships with calibrated flow sources, while plethysmographs use pressure chambers and known pressure changes to verify volume estimations inside the body. Kymographs are historical recorders of respiratory activity and are not standardly calibrated with a syringe. So the instrument specifically calibrated with a super syringe is the spirometer.