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Interpretation Response #06-0194 ([North American Automotive Hazmat Action Committee] [Mr. Dave Madsen])

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

Interpretation Response Details

Response Publish Date:

Company Name: North American Automotive Hazmat Action Committee

Individual Name: Mr. Dave Madsen

Location State: UT Country: US

View the Interpretation Document

Response text:

Oct 13, 2006


Mr. Dave Madsen                  Reference No.: 06-0194
Hazardous Materials Analyst
North American Automotive Hazmat Action Committee
3350 Airport road
Ogden, UT 84405-1563

Dear Mr. Madsen:

This is in response to your August 21, 2006 letter regarding the transportation of two stage air bag modules under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). In your letter you describe a “dual stage” air bag or seatbelt pre-tensioner as a device that contains two explosive devices, the second of which is designed to deploy milliseconds after the first. You describe a scenario, in which the first stage deploys, but the second stage of the device does not and you ask if the used air bag or seatbelt pre-tensioner would constitute a new design type under 173.56.

The answer is no, the used device is not a new air bag or seatbelt pre-tensioner design type under § 173.56. When serviceable, a “two stage” air bag or seatbelt pre-tensioner that has mis-fired (i.e., one stage has not deployed) may be transported under the exception specified in § 173. 166(d)(4). When packaged, described, and offered for transportation in accordance with the provisions specified under § 173.166(d)(4), an EX number is not required.

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



Hattie L. Mitchell
Chief, Regulatory Review and Reinvention
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.56 New explosives-definition and procedures for classification and approval