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Interpretation Response #19-0041

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

Interpretation Response Details

Response Publish Date:

Company Name: Dangerous Goods Advisory Council

Individual Name: Del Billings

Location State: MD Country: US

View the Interpretation Document

Response text:

August 1, 2019

Del Billings
Technical Director
Dangerous Goods Advisory Council
7501 Greenway Center Drive, Suite 760
Greenbelt, MD  20770

Reference No. 19-0041

Dear Mr. Billings:

This letter is in response to your April 1, 2019, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to Materials of Trade (MOTs).  In your email, you note the MOT provisions in § 173.6(a)(1) specify package gross mass limits for materials in packing groups (PG) I, II, III, and for Other Regulated Materials (ORM-D).  You also note that hazardous materials without a packing group assigned, such as lithium batteries, do not have a gross mass indicated.  You ask whether it was PHMSA’s intent to exclude articles from MOTs eligibility and, if not, you request guidance on determining package gross mass limitations for articles such as lithium batteries.

In a final rule published in the Federal Register on January 8, 2015, [80 FR 1075], the Pipeline and Hazardous Materials Safety Administration (PHMSA) removed packing group assignments from the § 172.101 Hazardous Materials Table (HMT) entries for many articles (e.g. UN3480, Lithium ion batteries).  In the preamble of the final rule we stated “For articles, the packing group does not relate to the degree of hazard posed by the material but rather is assigned generically to the article.”  The revisions to the HMT were made to provide consistency for all articles listed in the HMT. 

It was not our intention in the HM-215M rulemaking to remove articles, such as lithium batteries, from MOTs eligibility.  However, under the MOTs exceptions in § 173.6, the packing group assignment is used to determine the maximum gross mass or capacity of a completed package.  Because lithium batteries are generally required to be offered in a packaging meeting the PG II performance level as prescribed in § 173.185(b)(3)(ii), lithium batteries transported as

MOTs are subject to the same quantity limitations as a PG II hazardous material (30 kg).  Thank you for bringing this to our attention.  We intend to clarify this matter in a future rulemaking action.

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


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

172.101, 173.6, 173.6(a)(1), 173.185(b)(3)(ii)

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
173.185 Lithium cells and batteries
173.6 Materials of trade exceptions