Journal of Applied Physiology · 1957 · 32 citations · 0 references
EngineeringPhysiologyInstrumentationPulmonary Function TestingPulmonologyMechanical VentilationPulmonary MechanicsRespiratory AssessmentRespiratory MonitoringRespiratory Monitoring InstrumentsVentilation InstrumentationAirflow MeasurementAirflow Measurement DevicesDynamic ResponseFlow-volume RelationshipsPhysical PropertiesRespiratory ImpedanceRespiratory Impedance MeasurementRespiratory Rate Measurement
The physical properties of three types of respiratory flowmeters were evaluated and discussed. The three types of meters studied had flow resistive elements consisting of concentric cylinders (meter A), of 2–325/in. screens (meter B) and of parallel vertical plates (meter C). Meter C gave a linear indication of flow to 12 l/sec. The calibration factors of meters B and C were minimally affected by condensation. The dead spaces of meters A, B and C were 41, 310 and 85 ml, respectively. The over-all impedance to respiratory flow was least in meters B and C. With certain restrictions all meters had good dynamic response curves. Submitted on September 21, 1956