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This page describes products and general use; it is not medical advice.
An apnea monitor is a complete system intended to alarm primarily when breathing stops, timed from the last detected breath. It is a monitor, not a treatment: it detects and alarms, and it does not deliver therapy the way a CPAP machine does. Who uses it: clinicians and caregivers in hospital or home settings where breathing is watched, most often for infants and young children; clinic staff, buyers and students use this page to understand the product class and the regulatory expectations behind it.
What is an apnea monitor?
Under 21 CFR 868.2377, an apnea monitor is “a complete system intended to alarm primarily upon the cessation of breathing timed from the last detected breath.” The regulation adds that the device also includes indirect methods of apnea detection, such as monitoring heart rate and other physiological parameters linked to the presence or absence of adequate respiration. The FDA classifies it as Class II (special controls).
The FDA uses two product codes for the same regulation: FLS, “Monitor, Apnea, Facility Use”, and NPF, “Monitor, Apnea, Home Use”. Both are Class 2 under 21 CFR 868.2377.
How does an apnea monitor work?
The FDA’s Class II special controls guidance for apnea monitors (issued July 17, 2002) describes the building blocks it expects:
- Two ways of detecting apnea. At least one primary (direct) means of detecting apnea and at least one secondary (indirect) means, for example heart rate.
- A timer. The monitor times the duration of an apneic episode and alarms when it passes the set limit.
- Sensor-fault alarms. A sensor fault alarm for both the primary and secondary means, activating within 5 seconds of a sensor failure.
- Alarms. Visible and audible alarms that follow ASTM F1463-93 or ISO 9703-1/-2, with the guidance’s modifications.
The guidance names example sensing methods. Impedance pneumography, inductive plethysmography and pneumatic abdominal sensors detect central apnea only. Airway thermistors, carbon dioxide sensors and proximal airway pressure sensors detect both central and obstructive apnea without distinguishing them. Respiratory inductance plethysmography can detect both and distinguish between them.
Types of apnea monitor
| Type | Typical use | Key difference (source) |
|---|---|---|
| Facility use (FLS) | Healthcare facility | Product code FLS, Class 2, 21 CFR 868.2377 (openFDA classification) |
| Home use (NPF) | Home | Product code NPF, Class 2, 21 CFR 868.2377; the FDA guidance calls for a remote alarm unit on home monitors (FDA product classification; FDA guidance) |
| Central-apnea-only detection | Monitors using impedance, inductive plethysmography or abdominal sensors | Labeling must state that the device cannot detect obstructive apnea (FDA guidance, section 15) |
| Infant and pediatric | Infants and young children | Apnea duration setting defaults to 20 seconds; changing it needs a special tool or procedure and a visual signal when the setting is not 20 seconds (FDA guidance, section 12.1) |
Alarm and performance specifications that matter
The FDA guidance is written for manufacturers, so these are design expectations, not a shopping spec. They show what a compliant monitor is built to do.
| Item | What the FDA guidance says |
|---|---|
| Sensor-fault alarm | Within 5 seconds of a sensor failure |
| Audible alarm level | At least 75 dB(A) for home monitors; at least 70 dB(A) for hospital monitors |
| Silenced alarm | Alarms again within 2 minutes unless the cause is resolved |
| Disabling | Alarms cannot be permanently disabled; the visible alarm stays on until manually reset |
| Low-battery alarm | Activates 15 minutes to 2 hours before the battery has insufficient charge |
| Battery backup | Backup activates within 5 seconds of power failure; a home remote alarm unit should run at least 8 hours on a full charge |
| Infant and pediatric apnea duration | Defaults to 20 seconds |
The FDA lists ISO 18778 (2nd edition, 2022-06), “Respiratory equipment, particular requirements for basic safety and essential performance of infant cardiorespiratory monitors”, as a recognized consensus standard for product code NPF.
How to choose an apnea monitor
The sources do not give a ranking of monitors, and this page does not either. They do give the points a buyer or clinician can check against a manufacturer’s documentation:
- Which apnea type the sensors detect. Central-only devices must say in their labeling that they cannot detect obstructive apnea.
- Whether the device is cleared for facility (FLS) or home (NPF) use, and whether it lists the Class II regulation 21 CFR 868.2377.
- Whether the labeling explains sensitivity, positive predictive value and false alarm rate, which the guidance requires the caregiver manual to do.
- Whether alarm behavior matches the table above (sensor-fault, silencing, low-battery, remote alarm unit for home).
- Whether the manufacturer declares conformity to ISO 18778 or the alarm standards the guidance cites.
For related monitoring equipment, see choosing diagnostic patient monitoring equipment and the sleep clinic supply checklist. Suppliers list diagnostic, monitoring and imaging equipment as a product category.
Safe use and handling basics
Labeling the FDA guidance calls for includes these general points:
- A prescription (Rx) caution statement.
- A strangulation warning about wires and tubing; the guidance also asks for cable routing or retention features, especially for infants and young children.
- For home monitors, a warning not to plug the monitor into an outlet controlled by a wall switch.
- A recommendation in the caregiver manual that caregivers have CPR training.
Follow the manufacturer’s instructions for use.
Common mistakes
- Assuming a monitor detects every kind of apnea. A central-only device cannot detect obstructive apnea.
- Treating a monitor as therapy. It alarms; it does not treat.
- Overlooking the sensor-fault and low-battery alarm requirements when comparing documentation: they exist because a failed sensor or battery means the monitor may not detect an event.
FAQ
What is an apnea monitor?
A complete system intended to alarm primarily upon the cessation of breathing, timed from the last detected breath, which may also use indirect measures such as heart rate (21 CFR 868.2377). It is a Class II device in the United States.
What is the difference between facility and home apnea monitors?
The FDA assigns product code FLS to facility-use monitors and NPF to home-use monitors; both fall under 21 CFR 868.2377. The FDA guidance expects home monitors to include a remote alarm unit.
Does an apnea monitor detect obstructive apnea?
Only if its sensing method does. Central-apnea-only devices must state in their labeling that they cannot detect obstructive apnea.
Sources
Checked 2026-10-31.
- 21 CFR 868.2377, Apnea monitor: https://www.ecfr.gov/current/title-21/chapter-I/subchapter-H/part-868/subpart-C/section-868.2377
- FDA, Class II Special Controls Guidance Document: Apnea Monitors; Guidance for Industry and FDA (issued July 17, 2002): https://www.fda.gov/medical-devices/guidance-documents-medical-devices-and-radiation-emitting-products/apnea-monitors-class-ii-special-controls-guidance-document-industry-and-fda
- FDA product classification, NPF “Monitor, Apnea, Home Use”: https://www.accessdata.fda.gov/scripts/cdrh/cfdocs/cfpcd/classification.cfm?ID=NPF
- openFDA device classification, product code FLS “Monitor, Apnea, Facility Use”: https://api.fda.gov/device/classification.json?search=product_code:FLS
