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Interpretation Response #05-0123 ([Currie Associates, Inc.] [Mr. Eric Adair ])

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

Interpretation Response Details

Response Publish Date:

Company Name: Currie Associates, Inc.

Individual Name: Mr. Eric Adair 

Location State: NY Country: US

View the Interpretation Document

Response text:

Nov 9, 2005


Mr. Eric Adair                       Reference No. 05-0123
Director, Training and Consulting Services
Currie Associates, Inc.
10 Hunter Brook Lane
Queensbury, New York 12804

Dear Mr. Adair:

This is in response to your letter and e-mails concerning how to class and transport a prototype ultra capacitor that has no electrical charge when first shipped. You state that the device contains an aluminum electrode coated with carbon surrounded by 190-215 milliliters of a 1.0 Molar solution of tetraethylammonium tetrafluoroborate dissolved in acetonitrile. You also state the solution has a flash point of approximately 38 °F, and does not meet the criteria for a Division 6.1 (toxic) material. You ask whether the capacitor by itself or when installed in a power generation system is subject to the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).

The devices, alone or assembled into a larger power generation system, are subject to the HMR. Under § 173.22, it is the shipper’s responsibility to properly class a hazardous material. This office does not generally perform this function. However, based on the information provided and consultation with our scientific staff, it is our opinion that the electrolyte solution contained in the ultra capacitor device is a Class 3 (flammable).

When transported individually, the uncharged capacitors may be described as “Dangerous Goods in Machinery, 9, UN 3363” or “Dangerous Goods in Apparatus, 9, UN 3363,” since the quantity of hazardous material contained in each capacitor does not exceed 0.5 liters (see § 173.222(c)(2)). A completed power generation system composed of individual i1tra capacitors is considered a single item of equipment or single apparatus for purposes of the HMR. The power generation system must be classed and described based on the hazards that are present in the system’s capacitors, as defined in 49 CFR Part 173. Therefore, the system may be described as “Flammable liquids, n.o.s. (acetonitrile), 3, UN 1993, PG II.” If the: power generation system is described as a “Dangerous Goods in Machinery” or “Dangerous Goods in Apparatus” and the aggregate content of hazardous material in the system exceeds 0.5 liters, the system may be transported only under the terms of an exemption. If a capacitor is shipped charged, either individually or in a power generation system, it would also have to be shipped under the terms of an exemption. The requirements for applying for an exemption are found in § 107.105.

You also ask if the ultra capacitors maybe transported in accordance with § 172.102, Special Provision (SP) 136, which provides an exception from requirements in the HMR, with approval from the Associate Administrator for Hazardous Material Safety, for equipment, machinery, or apparatus that meets certain conditions. The capacitors do not qualify for the approval provision in SP 136 because the quantity of hazardous material contained in the capacitors exceeds that specified in § 173.4.

I hope this information is helpful.



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


Regulation Sections

Section Subject
173.222 Dangerous goods in equipment, machinery or apparatus