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This page describes products and general use; it is not medical advice.
A PEEP valve is a small accessory that fits the exhalation port of a manual resuscitator (bag-valve-mask) and holds a set amount of pressure in the patient circuit at the end of each breath out. Clinic staff, equipment buyers and students use this page to tell the main valve designs apart and to see what the manufacturers’ own instructions for use (IFU) say must be checked before one is put into service. The two IFUs cited below are examples from two manufacturers, not a survey of the market.
What a PEEP valve is
PEEP stands for positive end-expiratory pressure. One manufacturer IFU describes its valve as designed “to be used in conjunction with a manual resuscitation bag exhalation port to allow the user to select positive end expiratory pressure from 5 to 20cm H2O.” The valve is an accessory rather than part of every resuscitator: that IFU lists the PEEP valve and a disposable pressure manometer as optional accessories, and says that if PEEP is not desired the valve is removed. For the resuscitator itself, see what a bag-valve-mask is.
Who uses it: both IFUs restrict use to trained personnel. One says the device is to be used only by qualified personnel in the techniques of pulmonary resuscitation; the other says only medical personnel specifically trained in the use of manual resuscitators should operate the unit.
How it is built and where it fits
In the add-on design, the valve attaches to the resuscitation bag’s exhalation port. The IFU states that attaching it “requires no modification to either the resuscitator or valve,” and its body carries graduations at approximate PEEP levels of 5, 10, 15 and 20 cm H2O. The IFU describes the valve as a one-way valve intended for respiratory use only.
In the built-in design, the resuscitator already contains the valve. The second IFU describes “a threshold resistor-type PEEP valve” that lets the operator deliver variable positive end-expiratory pressure; if PEEP is not wanted, the indicator is set at the MINIMUM marking on the pressure scale label.
Types and variants
| Type | Typical use | Key difference | Source |
|---|---|---|---|
| Add-on adjustable PEEP valve | Fitted to the exhalation port of a manual resuscitator when PEEP is wanted | Separate accessory; removed when PEEP is not desired; dial graduations are approximate | Bound Tree Medical VT Select BVM IFU |
| Built-in threshold-resistor PEEP valve | Part of a resuscitator that offers variable PEEP | No separate part to fit; set to the MINIMUM marking for no PEEP | Air Life BagEasy IFU |
Valve designs for anesthesia breathing systems are a separate topic. A 1990 article from the Anesthesia Patient Safety Foundation (APSF) newsletter describes unidirectional valves that, if inserted incorrectly, can cause “a total or near total obstruction of the breathing system,” and bi-directional valves that add a second flow channel with its own one-way valve so that, if reversed, PEEP is not delivered but the system is not obstructed. It is a dated article and is cited here only for those design concepts.
Ranges and specifications that matter
| Item | What the IFU states | Source |
|---|---|---|
| Add-on valve setting range | 5 to 20 cm H2O, with graduations at approximate levels of 5, 10, 15 and 20 cm H2O | Bound Tree Medical IFU |
| Built-in valve calibrated scale | 4 to 20 cm H2O (printed with a tolerance of 4 cm H2O); minimum setting below 3 cm H2O; maximum above 20 cm H2O | Air Life BagEasy IFU |
| Accuracy of dial markings | Graduations are approximate; verify the PEEP setting with a manometer before use | Bound Tree Medical IFU |
| Actual pressure versus set value | May vary with patient lung compliance and resistance; verify pressure with a manometer | Both IFUs |
| Oxygen flow effect | Very high incoming oxygen flow may cause inadvertent PEEP; at 30 L/min, inadvertent PEEP may exceed 3 cm H2O | Air Life BagEasy IFU |
These are values for the two products named, not universal specifications. Connector sizes differ by product and are not generalised here.
How to choose: what the IFUs ask you to confirm
The IFUs do not rank products. They do state criteria that matter before a valve is put into service:
- Compatibility with the resuscitator. The add-on valve is made to fit the exhalation port of a manual resuscitation bag; confirm the valve is intended for the resuscitator in use.
- Range. Compare the stated range (for example 5 to 20 or 4 to 20 cm H2O) with the range the product is documented to provide.
- A way to verify pressure. Both IFUs call for a manometer to verify PEEP; one lists a disposable pressure manometer as an optional accessory.
- Intended circuit. The add-on valve’s IFU says it must not be used on anesthesia circuits.
Safe use and handling basics
- Read all instructions and test each unit before use (Air Life IFU); check that the valve is free of obstructions and verify function (Bound Tree IFU).
- Do not use PEEP unless pressure is verified with a manometer (Bound Tree IFU). Monitor the patient’s condition throughout.
- The Bound Tree IFU warns that PEEP may produce adverse effects and calls for close observation in low circulatory blood volume, impaired cardiac function, bullous lung disease and higher than normal lung compliance.
- The Air Life IFU says not to use PEEP unless thoroughly trained in its indications, contraindications and side effects, and unless it has been ordered by a physician.
- The add-on valve is not intended to be disassembled by the user, and the IFU cautions that sterilization or cleaning solutions may leave it nonfunctional.
- Disposal: for the Bound Tree product, the IFU says to discard the valve after use, and to remove and discard it if it becomes occluded. Check the IFU of any other product for its own reuse rule.
Common mistakes
- Trusting the dial. The IFU calls the graduations approximate and tells users to verify with a manometer.
- Leaving PEEP on when it is not wanted. The add-on valve is removed, or the built-in valve set to its MINIMUM marking. The APSF article makes the related point that an adjustable valve left in a circuit can easily deliver PEEP to a patient who would not tolerate it well.
- Ignoring a blocked valve. The Bound Tree IFU says an occluded valve is removed from the port and discarded.
- Using it on the wrong circuit. The add-on valve is not for anesthesia circuits.
- Overlooking oxygen flow. High incoming flow can produce unintended PEEP on the built-in valve.
FAQ
What is a bag valve mask PEEP valve?
It is an adjustable accessory, or a built-in feature, on a manual resuscitator’s exhalation side that holds a set pressure at the end of exhalation. One IFU describes it as letting the user select PEEP from 5 to 20 cm H2O.
Is a PEEP valve single use?
It depends on the product. The Bound Tree Medical IFU says to discard the valve after use. Follow the IFU for the specific valve.
Do I need a manometer with it?
Both IFUs say to verify PEEP with a manometer, and the Bound Tree IFU says not to use PEEP unless pressure is verified.
Can it be used on an anesthesia circuit?
The add-on valve’s IFU says no: it is a one-way valve for respiratory use only and must not be used on anesthesia circuits.
Related reading: what a ventilator is, pulse oximeters, oxygen concentrators and what counts as a medical device. Supplies for this area are listed under emergency and trauma supplies.
Sources
All sources below were checked on 2026-10-30.
- Bound Tree Medical, VT Select BVM with Manometer, Instructions for Use (manufacturer PDF), checked 2026-10-30: cdn.boundtree.com
- Air Life, BagEasy Resuscitator Instructions (562136), manufacturer paper insert, checked 2026-10-30: connect.myairlife.com
- J.B. Cooper, “Unidirectional PEEP Valves Can Cause Safety Hazards,” APSF Newsletter, Vol 5 No 3, Fall 1990, checked 2026-10-30: apsf.org
