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Interpretation Response #06-0180 ([HMT Associates, L.L.C] [Mr. E.A. Altemos ])

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

Interpretation Response Details

Response Publish Date:

Company Name: HMT Associates, L.L.C

Individual Name: Mr. E.A. Altemos 

Location State: VA Country: US

View the Interpretation Document

Response text:

Oct 12, 2006


Mr. E.A. Altemos                 Reference No. 06-0180
HMT Associates, L.L.C.
603 King St., Suite 300
Alexandria, VA 22314-3105

Dear Mr. Altemos:

This is in response to your August 1, 2006 letter regarding the proper classification, description, and associated transportation requirements for materials under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you state your product, solid carbon dioxide, contains an ozone concentration which is above the typical naturally-occurring concentrations and has been added to your product during the manufacturing process. You ask whether, because the ozone concentration in your material does not meet the definition of a Division 2.3 gas, the proper shipping name, “Carbon dioxide, solid or Dry ice” (UN 1845) is the proper classification and description of your material.

Section 173.22 of the HMR requires a shipper to properly class and describe the hazardous material in accordance with Parts 172 and 173 of the HMR, and to determine that the packaging or container is an authorized packaging in accordance with Part 173. This Office does not perform that function. However, if you determine that the ozone concentration does not meet the definition of any hazard class or division in the HMR, including Division 2.3, and is not a hazardous substance or hazardous waste, “Carbon dioxide, solid or Dry ice” (UN 1845) would be the proper classification and description of your material.

I hope this information is helpful.



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

173.22, 173.115

Regulation Sections

Section Subject
173.115 Class 2, Divisions 2.1, 2.2, and 2.3-Definitions
173.22 Shipper's responsibility