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Interpretation Response #03-0284 ([Oklahoma Liquefied Petroleum Gas Administration] [Mr. W.A. Glass])

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

Interpretation Response Details

Response Publish Date:

Company Name: Oklahoma Liquefied Petroleum Gas Administration

Individual Name: Mr. W.A. Glass

Location State: OK Country: US

View the Interpretation Document

Response text:

Oct 20, 2004


Mr. W.A. Glass                 Reference No. 03-0284
Oklahoma Liquefied Petroleum Gas Administration
2101 North Lincoln Boulevard
Oklahoma City, OK 73105

Dear Mr. Glass:

This is in response to your November 6, 2003 letter requesting clarification regarding bobtails and the applicability of the term “cargo tank motor vehicle” as specified in the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). A “bobtail,” as specified in the context of this letter, is a cargo tank that is not mounted to a trailer. Specifically, you ask if the definition for the term “cargo tank motor vehicle,” as referenced in § 173.3 15(n), is only applicable to bobtails. Please accept my apology for our delay in responding to your letter.

The answer is no. The term “cargo tank motor vehicle,” applies to all configurations of cargo tank motor vehicles. See enclosure. Section 171.8 defines “cargo tank motor vehicle” as a motor vehicle with one or more cargo tanks permanently attached to or forming an integral part of the motor vehicle. A “motor vehicle” as a defined in § 171.8, includes a vehicle, machine, tractor, trailer, or semitrailer, or any combination thereof, propelled or drawn by mechanical power and used on highways to transport passengers or property. Therefore, a cargo tank that is attached to a motor vehicle chassis, including a trailer or semitrailer, is considered a “cargo tank motor vehicle.”
I hope this information is helpful. Please contact us if you require additional assistance.



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


171.8, 173.315(n)

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
173.315 Compressed gases in cargo tanks and portable tanks