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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #03-0301 ([National Cargo Bureau, Inc.] [Captain Sam Rogers])

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

Interpretation Response Details

Response Publish Date:

Company Name: National Cargo Bureau, Inc.

Individual Name: Captain Sam Rogers

Location State: NY Country: US

View the Interpretation Document

Response text:

Jan 26, 2004


Captain Sam Rogers                Reference No. 03-0301

National Cargo Bureau, Inc.

17 Battery Place

Suite 1232

New York, NY 10004

Dear Captain Rogers:

This responds to your November 25, 2003 letter requesting clarification of the applicability of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to the transportation of forbidden hazardous materials and a shipper's responsibility for classifying a material.  Specifically, you ask about a material that is likely to decompose or polymerize below certain temperatures.

As your letter indicates, the HMR permit a material that is packaged, marked, classed, labeled, placarded, described, stowed and segregated, and certified in accordance with the IMDG Code to be offered and accepted for transportation in the United States under certain conditions (see §171.12(b)). Materials forbidden for transportation under the HMR may not be transported under the provisions of this section.

Section 173.21 lists materials and packages that are prohibited for transportation under the HMR.  You are correct that, in accordance with paragraph (f) of this section, a package containing a material that is likely to decompose with a self-accelerated decomposition temperature (SADT) of 50E C or less, or polymerize at a temperature of 54E C or less with an evolution of dangerous gas when decomposing or polymerizing may not be transported unless the material is stabilized or inhibited in a manner that precludes such decomposition.  This provision applies to any material, whether previously classified or not.  For transportation by vessel, such materials must be transported in accordance with the controltemperature requirements of section 21 of the General Introduction of the IMDG Code.

You also ask us to confirm that a shipper is responsible for classing a hazardous material in accordance with the HMR and, specifically, for SADT testing of a material.  Your understanding is correct.  Under the HMR, it is the shipper's responsibility to determine the hazard class of a material and for performing the tests necessary to make this determination.

I hope this information is helpful.



Susan Gorsky

Senior Transportation Regulations Specialist

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
173.21 Forbidden materials and packages