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Interpretation Response #98-0314 ([HMT Associates, L.L.C.] [Mr. Gordon Rousseau])

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. Gordon Rousseau

Location State: DC Country: US

View the Interpretation Document

Response text:

DEC 3, 1998


Mr. Gordon Rousseau                 Reference. No. 98-0314
HMT Associates, L.L.C.
1850 K Street, NW
Washington, DC 20006-3500

Dear Mr. Rousseau:

This is in response to your letter dated October 16, 1998, and October 26, 1998 telephone conversation with Ms. Eileen Mack of my staff, concerning a requirement in 49 CFR 173.33(a)(2) against loading materials on the same cargo tank motor vehicle that, if mixed, would cause would an explosion, vehicle fire, excessive increase in pressure or heat, or the release of toxic vapors. You described a situation in which a multi-cargo tank motor vehicle is loaded with two materials that would significantly react when mixed. These materials are separated by a middle compartment containing a neutral, non-regulated material. You asked if this loading arrangement is acceptable.
Based on the information you provided, the answer is no. The restriction in § 173.33(a)(2) pertains to the loading of incompatible materials on the same cargo tank motor vehicle. Therefore, the restriction applies regardless of whether the incompatible materials on the cargo tank: motor vehicle are separated by a compartment containing a neutral material.

I hope this satisfies your request.



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


Regulation Sections

Section Subject
173.33 Hazardous materials in cargo tank motor vehicles