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Interpretation Response #12-0137 ([Data Domain, BRS Division of EMC Corporation] [Mr. Kendall Wilcox])

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

Interpretation Response Details

Response Publish Date:

Company Name: Data Domain, BRS Division of EMC Corporation

Individual Name: Mr. Kendall Wilcox

Location State: CA Country: US

View the Interpretation Document

Response text:

Mr. Kendall Wilcox
Data Domain, BRS Division of EMC Corporation
2421 Mission College Blvd.
Santa Clara, CA 95054
Ref. No.: 12-0137

Dear Mr. Wilcox:

This responds to your June 24, 2012 letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the requirements for lithium batteries. In your letter, you describe a 7.2V battery pack that consists of two United Nations (UN) Manual of Tests and Criteria (UN 38.3) tested lithium ion cells connected in series. The battery pack itself has been tested under section 38.3 of the UN Manual of Tests and Criteria and incorporates protective circuitry. You install these battery packs in your systems, which incorporate a charging circuit. You state that there are between 3 and 6 battery packs on each system, each with its own identical charging circuit. The packs are connected in parallel to provide 7.2V power and are protected via fusing and diodes to prevent reverse currents between packs. In addition, the packs and charging circuits have been evaluated for compliance with UL2054 battery regulations. You ask if the final connected system, as shown in your attached diagram, must be evaluated to the UN 38.3 transportation test. If so, you ask whether every system needs to be tested or can a single system be used to represent all of them, assuming all of the protection circuitry is identical.

It is the opinion of this Office that in your scenario, each battery assembly, with different numbers of battery packs, would not require additional testing under UN 38.3. Based on your scenario, the final connected system you describe does not appear to be a battery assembly as described in UN 38.3(f). Under this section, the battery assembly is not required to undergo tests 3, 4, 5 and, in addition, test 7 in the case of a rechargeable battery assembly.

I hope this satisfies your inquiry. Please contact us if we can be of further assistance.


T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

Regulation Sections

Section Subject
173.185 Lithium cells and batteries