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Interpretation Response #03-0049 ([Latham & Watkins LLP] [Mr. Kelly E. Richardson])

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

Interpretation Response Details

Response Publish Date:

Company Name: Latham & Watkins LLP

Individual Name: Mr. Kelly E. Richardson

Location State: CA Country: US

View the Interpretation Document

Response text:

May 20, 2003


Mr. Kelly E. Richardson                Reference No. 03-0049
Latham & Watkins LLP
701 B Street, Suite 2100
San Diego, CA 92101-6197

Dear Mr. Richardson:

This responds to your January 29, 2003 letter regarding the applicability of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to the transportation of certain ultracapacitors.  Your letter states that the ultacapacitors, which are approximately the size of a quarter, are comprised of a sealed steel container that encloses layers of activated carbon, metal and plastic.  The activated carbon is saturated with an electrolyte solution and the electrolyte contains quaternary salt and a small amount (1.5 grams or less) of acetonitrile.  The ultracapacitors in question are the Maxwell models PC-5 and PC-10.  You also submitted photographs and a test report from Underwriters Laboratories, Inc.  Specifically, you ask whether the ultracapacitors are subject to the HMR.  I apologize for the delay and any inconvenience it may have caused.

Based on the information you provided, it is our determination that 1.5 grams or less of acetonitrile in a sealed steel container is in a quantity and form that does not pose a hazard in transportation.  Therefore, the ultacapacitors are not subject to the HMR.

I hope this satisfies your request.



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


Regulation Sections

Section Subject
171.1 Applicability of Hazardous Materials Regulations (HMR) to persons and functions