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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #21-0103

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

Interpretation Response Details

Response Publish Date:

Company Name: Eos Energy Storage

Individual Name: Heidi Countermine

Location State: NJ Country: US

View the Interpretation Document

Response text:

February 24, 2022

Heidi Countermine
Project Logistics Manager
Eos Energy Storage
3920 Park Ave.
Edison, NJ  08820

Reference No. 21-0103

Dear Ms. Countermine:

This letter is in response to your November 11, 2021, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to electric storage batteries. Specifically, you seek confirmation that the shipment of your company’s electric storage batteries is eligible for the exception from the requirements of the HMR as currently specified in § 173.159(e).

In your letter, you state that your company manufactures an electric storage battery and loads the product into a fully enclosed energy storage system—i.e., a custom-built ISO container—under certain conditions including the following:

The batteries are classified and described as "UN2794, Batteries, wet, filled with acid, electric storage, 8".

Each individual battery is enclosed in plastic housing with no exposed terminals.

The batteries are loaded and braced into individual slots in the steel racks of the custom-built container, and provide a photograph illustrating this manner of loading and bracing.

No other hazardous materials are shipped in or with this fully enclosed container.

he motor vehicle or rail car will not contain any other commodities.

Based on the information and photographs provided, it is the opinion of this Office that the details provided of shipments of these batteries meet the requirements provided in § 173.159(e) for exception from the requirements of the HMR.

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
173.159 Batteries, wet