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Interpretation Response #06-0196 ([Quarles & Brady LLP] [Mr. Lars E. Guibrandsen])

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

Interpretation Response Details

Response Publish Date:

Company Name: Quarles & Brady LLP

Individual Name: Mr. Lars E. Guibrandsen

Location State: WI Country: US

View the Interpretation Document

Response text:

Oct 13, 2006


Mr. Lars E. Guibrandsen                 Reference No. 06-0196
Quarles & Brady LLP
411 East Wisconsin Avenue
Milwaukee, Wisconsin 53202-4497

Dear Mr. Gulbrandsen:

This responds to your letter dated August 17, 2006 regarding the applicability of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to a motor vehicle, operating under its own motive power that stores energy during braking in a large compressed gas accumulator containing nitrogen.

According to your letter, your client plans to manufacture and sell an auxiliary power system for trucks, such as garbage trucks. The auxiliary power system is similar in purpose to batteries incorporated into hybrid-electric vehicles. The auxiliary power system stores the energy generated during braking in a large compressed gas accumulator containing nitrogen, and then releases that energy to produce better fuel economy. Specifically, you ask if your understanding is correct that § 173.220 applies to the transportation of a self-propelled vehicle “when transported as cargo” on a transport vehicle, but would not apply when a self-propelled vehicle is operated under its own motive power.

Your understanding is correct. The requirements in § 173.220 do not apply to a self- propelled vehicle carried as cargo on a transport vehicle and operated under its own motive power.

I hope this satisfies your inquiry. If we can be of further assistance, please contact us.



John A.
Chief, Standards Development
I Office of Hazardous Materials Standards

173.220, 173.301

Regulation Sections

Section Subject
173.220 Internal combustion engines, vehicles, machinery containing internal combustion engines, battery-powered equipment or machinery, fuel cell-powered equipment or machinery
173.301 General requirements for shipment of compressed gases and other hazardous materials in cylinders, UN pressure receptacles and spherical pressure vessels