How Non-Rebreather Masks Work

Non-Rebreather Mask – What Is It?

The non-rebreather mask (NMR) is a device used to breathe underwater without using air. The NMR works like a diver’s breathing apparatus except it does not require oxygen or any other gas. You are able to breath under water for longer periods of time with the NMR than you could while wearing an air tank on your back.

How Does It Work?

There are two parts to the NMR: The first part is a mask which fits over your face and allows you to breathe through it. The second part is a regulator which regulates the amount of air that enters and leaves your body. When you put on the mask, some of the oxygen in your blood gets trapped inside it. When you exhale, the oxygen escapes out of the mask. The result is that your lungs get filled with oxygen at all times. Your body uses up less oxygen when you are underwater because there is no need to replace it.

Benefits Of Using A Non-Rebreather Mask?

You can stay underwater for longer periods of time without needing to worry about getting suffocated or drowning due to lack of air.

Who Can Use It?

Anyone can use a non-rebreather mask. However, it is mandatory that you undergo training before using one. If you don’t know how to use it properly, the results could be fatal.

Which Sport Or Activity Can I Use A Non-Rebreather Mask For?

You can use this device for almost any activity that you engage in underwater. It is commonly used for scuba diving, but it can be used for other aquatic endeavors as well. The only time you shouldn’t use it is when you are swimming at shallow depths or around shallow water since the device blocks your vision and restricts your movement.

Sources & references used in this article:

Evaluation of the self-inflating bag-valve-mask and non-rebreather mask as preoxygenation devices in volunteers by A Robinson, A Ercole – BMJ open, 2012 –

Reliability of methods to estimate the fraction of inspired oxygen in patients with acute respiratory failure breathing through non-rebreather reservoir bag oxygen mask by R Coudroy, JP Frat, C Girault, AW Thille – Thorax, 2020 –

Methods for evaluation of helium/oxygen delivery through non-rebreather facemasks by AR Martin, IM Katz, Y Lipsitz… – Medical gas …, 2012 – medicalgasresearch.biomedcentral …

Effect of preoxygenation using non-invasive ventilation before intubation on subsequent organ failures in hypoxaemic patients: a randomised clinical trial by C Baillard, G Prat, B Jung, E Futier, JY Lefrant… – British journal of …, 2018 – Elsevier