Unique status as both calibration gas mixtures and medical gases

The gas mixtures used to calibrate pulmonary function test equipment or lung function test medical diagnostic devices are also the same gases that are breathed by patients during the test. This gives them a rather unique status in the world of specialty and medical gases because they are both consumed by the patient and used for device calibration. This requires manufacturing to be done in line with good manufacturing practice for medical gases and additionally requires them to be high precision certified calibration gas mixtures. They therefore have quality control aspects common to both medical gases and specialty gases products groups. They do, however, differ from core medical gases such as medical oxygen or medical nitrous oxide because they are used for diagnostic, not therapeutic, applications.