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Interpretation Response #21-0052

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

Interpretation Response Details

Response Publish Date:

Company Name: Amazon

Individual Name: Marianna Patterson

Location State: DC Country: US

View the Interpretation Document

Response text:

July 29, 2021

Ms. Marianna Patterson
Manager, Amazon Public Policy
601 New Jersey Avenue, NW
Washington, DC  20001

Reference No. 21-0052

Dear Ms. Patterson:

This letter is in response to your May 12, 2021, email and previous phone conversations requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to packaging of lithium batteries. Specifically, you ask whether a flexible overpack can be used to transport smaller lithium cells or batteries contained in equipment, which are packaged in retail packaging. Furthermore, you indicate the retail packaging is sturdy, durable, constructed to retain the contents under normal conditions of transportation, and meets the outer packaging requirements of § 173.185.

The answer is yes. The HMR defines an overpack (see § 171.8)—except as provided in subpart K of part 178—as "an enclosure that is used by a single consignor to provide protection or convenience in handling of a package or to consolidate two or more packages." Therefore, if the retail packaging meets the outer packaging requirements for smaller lithium cells or batteries contained in equipment (i.e., packaging requirements of the HMR including §§ 173.24, 173.24a, and 173.185), the flexible packaging would meet the definition of an overpack.

See § 173.25 for additional overpack requirements.

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

171.8, 173.24, 173.24a, 173.25, 173.185

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
173.185 Lithium cells and batteries
173.24 General requirements for packagings and packages
173.24a Additional general requirements for non-bulk packagings and packages
173.25 Authorized packagings and overpacks