Each Calibration Syringe has a label indicating the model, serial number, date and calibrated volume. The calibrated mechanical stop in each Calibration Syringe provides an accurate and repeatable volume standard appropriate for spirometer calibration. The mechanical stop has its corresponding volume calibrated with a volumetric apparatus certified to meet the accuracy requirements of the National Bureau of Standards Circular 602. In addition, each syringe is 100% leak tested and traceable to NIST standards. A-M Systems aluminum calibration syringes are CE marked.
High Accuracy at a Low Cost: The Calibration Syringes manufactured here at A-M Systems offer users a low cost method for calibrating the volume measurements for pulmonary function analyzers. Analyzers need to be periodically checked against a known volume to ensure that they are in calibration. It is poor practice to rely on an internal calibration procedure without a known volume standard. Studies have shown that pulmonary function analyzers may give erroneous results (N Engl J Med. 1973 Dec 13;289(24):1283-8).
Why a 3-Liter Syringe? A-M Systems offers a 3-liter size to meet international standards and requirements for spirometry equipment. In "Standardisation of spirometry," the American Thoracic Society and the European Respiratory Society recommend the following:
With regards to volume accuracy, calibration checks must be undertaken at least daily, using a 3-L syringe discharged at least three times to give a range of flows varying between 0.5 and 12 L•s-1 (with 3-L injection times of ~6 s and <0.5 s).