Non-Rebreather Masks: 5 Interesting Facts You Need to Know

Apr 11, 2022

Non-Rebreather Masks: 5 Interesting Facts You Need to Know

If you are familiar with oxygen therapy, you’ve doubtless heard about oxygen masks. Still, it might surprise you to learn just how many different kinds of oxygen masks there are. One of the less common mask types is the non-rebreather mask.

What is a non-rebreather mask and how does it work?

A non-rebreather mask (NRB) is a medical device used to prevent hypoxaemia — or low blood oxygen — in emergencies. These masks are low-flow devices, as the non-rebreather mask flow rate is lower than the patient’s inspiratory flow rate (the rate at which the patient inhales).

Like other oxygen masks, non-rebreather masks fit over the nose and mouth and are held in place by an elastic band. One end of the mask connects to a reservoir bag that contains a high concentration of oxygen. The reservoir bag is connected to an oxygen source such as an oxygen tank. Once fitted with a mask, patients will breathe in the oxygen from the reservoir and exhale air naturally, where it will escape through small vents in the sides of the mask.

Sounds pretty indistinguishable from any other oxygen mask, right? While non-rebreather masks share many similarities with simple oxygen masks and other oxygen delivery devices, there are a few things that make them stand out. Here are five non-rebreather mask facts that might interest you.

1. Non-rebreather masks deliver some of the highest concentrations of oxygen.

Non-rebreather masks provide some of the purest oxygen concentrations of any low-flow oxygen delivery device, supplying anywhere from 60% to almost 100% oxygen. Compare that to other mask types:

  • A nasal cannula provides roughly 24% to 40% oxygen concentration.
  • Face tents deliver approximately 40% oxygen concentration.
  • Venturi masks provide oxygen concentrations between 24% and 50%.
  • Simple face masks provide 40% to 60% oxygen concentration.
  • A partial rebreather mask provides oxygen concentrations between 50% and 80%.

NRB masks can deliver such high oxygen concentrations due to their unique design. When using a non-rebreather mask, a one-way valve prevents outside air from entering the reservoir bag and mixing with the pure oxygen there. This helps ensure that the patient doesn’t inhale room air or re-inhale exhaled air.

2. These masks are only used in specific situations.

Non-rebreather masks are not ideal for every situation. They are most commonly used when a patient can still breathe for themselves but need oxygen quickly delivered to their blood. These masks are often used for cases of carbon monoxide poisoning, smoke inhalation or serious traumatic injuries.

3. They aren’t like other oxygen masks.

Not only do non-rebreather masks provide much higher oxygen concentrations, but they often have a higher oxygen flow rate as well. Their unique design — which includes a reservoir bag and valves — helps ensure that they stand out from other types of oxygen masks.

Of the various types of oxygen masks, NRB masks and PRB (partial rebreather) masks are the only two common options to utilize reservoir bags. Additionally, unlike simple oxygen masks, nasal cannula, face tents, and partial rebreathers, NRB masks limit patient intake of anything but pure oxygen.

4. NRB masks can be effective — and dangerous.

While these masks are highly useful and effective, they do come with risks. Most serious is the potential risk of suffocation, which can occur if the non-rebreather mask oxygen flow rate is interrupted. Because the mask forms a seal around the patient’s mouth and nose and does not allow room air in, a patient can only breathe when the mask is connected to a working oxygen tank.

5. These masks are not available for at-home use.

Unlike cannulas and simple face masks, non-rebreather masks are only used in emergencies and by trained medical professionals. You’re most likely to see them during emergency procedures or medical transport. Their high oxygen concentration levels and potential dangers make them unsuitable for at-home or oxygen therapy use.

Mega Medical: Meeting your at-home and in-clinic medical gas needs

If you’re a medical professional seeking non-rebreathing masks for your practice or a patient looking for at-home oxygen therapy solutions, Mega Medical is here to help. We’re proud to be one of Australia’s leading providers of medical equipment, including medical oxygen consumables, oxygen concentrators, resuscitation equipment and more.

Reach out to our friendly and knowledgeable staff for help with placing your order or for more information about our products and services today!