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Interpretation Response #11-0186 ([Mr. Tae Kim])

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

Interpretation Response Details

Response Publish Date:

Company Name:

Individual Name: Mr. Tae Kim

Location State: CA Country: US

View the Interpretation Document

Response text:

November 3, 2011



Mr. Tae Kim

9671 Irvine Center Drive

Koll Center II " Building 6

Irvine, CA 92618

Reference No.: 11-0186

Dear Mr. Kim:

This responds to your July 29, 2011 email requesting further clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the use and packaging of a chemical oxygen generator (COG). You request, based on the submission of new data, that the Pipeline and Hazardous Materials Safety Administration (PHMSA) reconsider a previously-issued letter of interpretation dated July 15, 2011 [Ref. No. 11-0108]. Specifically, in light of this new data, you seek written confirmation that the manner in which you are preparing and packaging your insulated handheld COG classified as "Oxygen generator, chemical (including when contained in portable breathing equipment (PBE), UN3356" is in compliance with the HMR.

In your original incoming email, you describe a scenario in which you purchased a COG whose design has been approved by the Associate Administrator of PHMSA. In addition, in your original incoming email, you included a document from the manufacturer of the packaging used to initially transport the COG which states the packaging that contains the COG has been successfully tested in accordance with § 173.168. Subsequently, you modified the COG by adding insulation to facilitate handheld use, and then repackaged the modified COG in the originally-tested and approved packaging. However, you modified the approved original packaging configuration by removing some of the inner packaging to accommodate the increased size of the modified insulated COG.

The new data and your rationale for requesting that PHMSA reconsider our opinion stated in our previous letter of interpretation [Ref. No. 11-0108] are paraphrased and addressed below. For purposes of clarity, the insulated handheld COG and the packaging used to contain the insulated handheld COG are addressed separately. It should be noted that PHMSA does not provide approvals for COGs through letters of interpretation. The requirements for submitting an approval application are specified in § 107.709 of the HMR.

The insulated handheld COG used as a PBE

In your follow-up email concerning the COG, you include the original source control schematic drawing of the approved COG, a schematic drawing of the preliminary PBE assembly that you developed using the approved COG, and the original approval issued by PHMSA. You indicate that the COG is the main component of the PBE. You also state that the COG is not tampered with, nor modified. Based on this information, it is your understanding that your PBE assembly containing a COG should fall within the design parameters of the originally approved COG and, therefore, is not required to be re-submitted for approval.

Provided your PBE, that includes the COG as its" main component, does not modify the originally approved COG, the COG would be permitted to be shipped under the original approval. Based on the original approval of the COG and the additional documentation you provided in your emails, it is the opinion of this Office that the addition of insulation to the COG would not merit the submittal of a new approval from the Associate Administrator of PHMSA in order to be shipped in compliance with the HMR.

The packaging containing the insulated handheld COG used as PBE

In your follow-up email, you also submit more specific details and data regarding the packaging design for your PBE assembly containing a COG and your rationale for requesting that PHMSA reconsiders its" opinion that your packaging would need to be subjected to the testing requirements specified in § 173.168.

You state it is your understanding that the COG itself, not the packaging, is tested for impact resistance as specified in § 173.168(b). Your understanding of this requirement is correct. Provided the COG is not modified from its approved design, the new COG design would not need to undergo impact resistance as specified in § 173.168(b).

You also state it is your understanding that the performance requirements for the packaging specified in § 173.168(d), including the flame penetration and thermal resistance tests are specific to the outer packaging. Thus, the removal of the plastic insert, which does not tamper with the outer packaging, does not affect the flame penetration and thermal resistance tests. Your understanding that the performance requirements for the packaging specified in

§ 173.168(d) refer to the "rigid outer packaging" is correct. Provided the outer packaging remains unchanged with the removal of a plastic divider, the packaging does not require re-testing in accordance with § 173.168(d).

In light of the additional data you provided, we are rescinding our previous letter of clarification. I hope this satisfies your inquiry. Please contact us if we can be of further assistance.


T. Glenn Foster

Chief, Regulatory Review and Reinvention Branch

Standards and Rulemaking Division

173.168, 107.709

Regulation Sections

Section Subject
173.168 Chemical oxygen generators