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Small, Light, and Effective – A Look at the Inogen One G3

by | May 3, 2013 | Inogen | 9 comments

Inogen One G2 and G3 Portable Oxygen Concentrators

As more people are discovering the benefits of portable oxygen concentrators, manufacturers are seeking to produce units that provide greater mobility. Smaller and lighter is the goal, without sacrificing clinical efficacy.

Inogen has been a leader in the portable concentrator market, being one of the first companies to offer a portable oxygen concentrator with their Inogen One POC. Never resting on their laurels, Inogen has since introduced a second-generation unit, the G2; and most recently, a third-generation unit, the G3. Each generation has been over 40% smaller, and 30% lighter, than its predecessor, with the new Inogen One G3 weighing less than five pounds.

How does the Inogen One G3 compare with other 5-pound portable concentrators?

Inogen is not the only manufacturer of portable concentrators weighing less than five pounds. The AirSep FreeStyle 3 has long been available, and the Inova LifeChoice Activox has recently come on the market. I’ve already stated that size matters, but if all the units are similar in size and weight, which is better?

The first question to ask is always, “Which one provides the most oxygen?” All three units provide pulse-only settings. While the FreeStyle and Activox provide up to setting 3, the Inogen One G3 provides up to setting 4. So if your oxygen needs are higher, the Inogen One G3 is the best choice.

Furthermore, according to a recent study of POCs weighing less than five pounds, completed by Strategic Dynamics, Inc., the Inogen One G3 offers the most oxygen for those with high breathing rates. They conclude:

First, the Inogen One® G3 produces and delivers more oxygen than the other POCs at all breathing frequencies, and has a higher range of settings (4 versus 3 or 1 for the other devices).

Second, and perhaps the most important finding from the standpoint of clinical application, is that oxygen delivery for all POCs in this study decreased as breathing frequency increased.

For example, at a setting of 2, the inspired oxygen concentration fell from a high of 23.5% at 19 breath per minute (Inogen One® G3) to a low of 21.9% at 35 breaths/min (CAIRE-Focus).

Only the Inogen One® G3 would be able to compensate for this by increasing the setting from 2 (at 19 breaths/min) to 4 (at 35 breaths/min) to maintain an inspired oxygen concentration of about 24%.

It appears the Inogen One G3 is a small powerhouse portable oxygen concentrator, ready to meet the demands of many oxygen users.


  1. Laura

    I just wanted to thank you for this review. I recently purchased the G3 for air travel, and it’s been great for the two trips I’ve been on. My liquid O2 system still works better for everyday use and exercise (slightly lighter weight, no mechanical noise, no waiting for the unit to “catch up” with increased breathing rates), but the G3 seems to be the best for travel. The G3 is light enough that I can carry it rather than rolling (as I had to do when I rented the G2), and it’s small enough to fit under the seat in the airplane along with my carry-on bag! Just FYI, I bought a 4-hour and 8-hour battery, and even the 8-hour battery isn’t too heavy or bulky.

  2. Lena Hurt

    I’m looking for a light weight concentator, I on 3 liters. I am currently on bottled canister with fanny pack. By useing 3 liters, I have to make sure I have at least 5 bottles with me. I have to carry 2 canisters in fanny pack. They not cause me more shortness of breath. It is not becoming to dressing up.

    • Allison Waters

      If you can use a pulse flow of oxygen, the Inogen One G3 is a great choice. It provides up to pulse setting 4 and the large battery lasts 6-7 hours on setting 3. With the large battery the Inogen One G3 weighs 6.25 pounds. You can also power it in the car with the DC power cord.

  3. Chelly

    I bought an used inogen one for my dad(87 yrs old) I am trying to figure out in the settings the amount of oxigen….he is been prescribed 1.5 l..is that setting number too? I can’t find the specs of settings! What amount they are? Please help! Thanks.

    • Allison Waters

      Yes, the settings on a portable oxygen concentrator are equivalent to the liter flow amount prescribed by the doctor. At least it is a starting point! You may need to increase the setting a notch or two to provide enough oxygen for your dad’s needs. The only way sure to know if he is getting enough oxygen is to use a fingertip pulse oximeter, which tells you his blood oxygen level.

      For more information about pulse flow settings, please see the Guide I wrote on that topic.

  4. Don Jones

    Does the Inogen G3 have a fanny pack for playing golf?

    • Allison Waters

      Inogen makes a backpack for the G3; however, I am not aware of a fanny pack.

  5. Joyce

    Where can I get a waist pack to carry the Inogen 3 ?

    • Allison Waters

      Unfortunately, I am not aware of a waist pack that can accommodate the Inogen One G3. This size of the unit makes carrying it around the waist prohibitive for most people. Perhaps the shoulder strap that is included with the carry bag can be adjusted to fit your waist.