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Interpretation Response #18-0105

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

Interpretation Response Details

Response Publish Date:

Company Name: Sidley Austin LLP

Individual Name: Judah Prero

Location State: DC Country: US

View the Interpretation Document

Response text:

October 15, 2018

Judah Prero
Sidley Austin LLP
1501 K Street NW
Washington, DC  20005

Reference No. 18-0105

Dear Mr. Prero:

This letter is in response to your July 11, 2018, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the classification of a lithium ion battery contained in a computer server power converter.  You describe a power converter that functions to convert externally supplied electricity from an alternating current to direct current for the operation of a computer server.  The power converter also contains a 32-volt (V) lithium ion battery to supply emergency power to the computer server in the event of external power failure.  You ask whether the power converter with a lithium ion battery installed should be classified as "UN3480, Lithium ion battery" or "UN3481, Lithium ion battery contained in equipment" when it is shipped to the server assembler.

The power converter must be classified as "UN3480, Lithium ion battery" when shipped to the server assembler.  For the purposes of lithium batteries, "equipment" is defined in § 173.185 as "the device or apparatus for which the lithium cells or batteries will provide electrical power for its operation."  The battery's purpose in the converter is to supply emergency power to the computer server; thus, it must be transported using a proper shipping name that most appropriately describes the battery type housed in the power converter.  However, once the power converter is installed into the computer server, the completed device, when transported, would be classified as "UN3481, Lithium ion battery contained in equipment."

I hope this information is helpful.  Please contact us if we can be of further assistance.


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division


Regulation Sections

Section Subject
173.185 Lithium cells and batteries