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Interpretation Response #09-0155 ([Inogen, Inc.] [Mr. Matt Scribner])

Below is the interpretation response detail and a list of regulations sections applicable to this response.

Interpretation Response Details

Response Publish Date:

Company Name: Inogen, Inc.

Individual Name: Mr. Matt Scribner

Location State: CA Country: US

View the Interpretation Document

Response text:

August 6, 2009




Mr. Matt Scribner
Inogen, Inc.
Bollay Drive
Goleta, CA 93117

Ref. No. 09-0155

Dear Mr. Scribner:

This responds to your July 6, 2009 letter requesting clarification of the applicability of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to a portable oxygen concentrator. You request confirmation that the Inogen One G2 portable oxygen concentrator is not subject to the HMR.

Your company previously requested an interpretation in 2004 on the applicability of the HMR to the Inogen One portable oxygen concentrator. In our March 24, 2004 letter responding to your request, we stated that the device is not subject to the HMR provided the device is packaged in conformance with § 173.21(c).

According to your letter, your company has made design improvements to Inogen One, which will be marketed as Inogen One G2. The new version includes an optional 24-cell lithium ion battery pack to power the device consisting of two independent 12-cell battery packs. Each 12-cell battery pack operates independently in the same manner as the 12-cell battery pack that was used to power Inogen One. Specifically, the battery packs are electrically isolated and mechanically separated when enclosed in the device. Your letter also indicates that: (1) each lithium ion cell has an equivalent lithium content of 0.66 gram; (2) the total equivalent lithium content of each 12-cell battery pack is 7.92 grams; (3) the batteries are contained in the device and packaged in a manner to prevent sparks or the generation of a dangerous evolution of heat; (4) the pressure of the oxygen in the device is less than 40.6 psia at 20 °C (68 °F); (5) and no other hazardous material subject to the HMR is contained in the device.

You should be aware that since our March 24, 2004 letter, we have amended the HMR provisions applicable to lithium batteries, including the exceptions for small and medium lithium batteries. In a final rule published August 9, 2007, under Dockets HM-224C and HM-224E (72 FR 44930; copy enclosed), we relocated the exceptions for small lithium batteries in § 173.185(b) to Special Provision 188 in § 172.102(c)(1). In addition, we removed the exception for medium lithium batteries for transported by air, including the exception for batteries up to 25 grams aggregate lithium content when fully charged. Further, we added a new provision, beginning October 1, 2009, that small lithium cells and batteries must be of a type proven to meet the performance standards for applicable tests in the UN Manual of Tests and Criteria.
Based on the information provided, the oxygen in the Inogen One G2 portable oxygen concentrator is not subject to the HMR as a Division 2.2 non-flammable gas. Moreover, it is the opinion of this Office that the Inogen One G2 portable oxygen concentrator described in your letter and the lithium ion batteries contained in the device conform to the provisions of Special Provision 188. Therefore, provided the provisions in Special Provision 188 continue to be met, the Inogen One G2 portable oxygen concentrator is not subject to any other requirements in the HMR.

The approval of the Federal Aviation Administration (FAA) is required before portable oxygen concentrators may be used by passengers onboard aircraft. The FAA published a final rule on July 12, 2005 (70 FR 40155; copy enclosed) regarding these devices. For further assistance, you may contact Mr. Dave Catey, Aviation Safety Inspector for the FAA Air Carrier Operations Branch (AFS-220) by phone at (202)-267-3732 or email at In addition, even with FAA approval, an air carrier ultimately determines what may or may not be carried on its aircraft. We suggest that you check with the airlines to ensure that the Inogen One G2 portable oxygen concentrator may be carried.

I hope this information is helpful. If you have further questions, please do not hesitate to contact this office.


Charles E. Betts
Chief, Standards Development
Office of Hazardous Materials Standards


1. August 9, 2007 Final Rule: "Hazardous Materials; Transportation of Lithium Batteries"

2. July 12, 2005 Final Rule: "Use of Certain Portable Oxygen Concentrator Devices Onboard Aircraft"

173.185, 173.21, 172.102 SP 188

Regulation Sections

Section Subject
173.185 Lithium cells and batteries
173.21 Forbidden materials and packages