21 CFR § 868.1850 - Monitoring spirometer.
(a) Identification. A monitoring spirometer is a device used to measure continuously a patient's tidal volume (volume of gas inhaled by the patient during each respiration cycle) or minute volume (the tidal volume multiplied by the rate of respiration for 1 minute) for the evaluation of the patient's ventilatory status.
(b) Classification. Class II (performance standards).