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Interpretation Response #23-0008

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

Interpretation Response Details

Response Publish Date:

Company Name: Leschaco, Inc.

Individual Name: Mr. Hien Le

Location State: TX Country: US

View the Interpretation Document

Response text:

November 14, 2023

Mr. Hien Le
Manager – Hazmat and Compliance
Leschaco, Inc.
15355 Vantage Parkway West, Suite 240
Houston, TX  77032

Reference No. 23-0008

Dear Mr. Le:

This letter is in response to your January 30, 2023, email concerning the use of a technical name as part of a proper shipping name under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, your email pertains to the shipment of dimethyl phthalate as "UN3082, Environmentally hazardous substance, liquid, n.o.s., 9, III." In your email, you note that the safety data sheet (SDS) for this material states the technical name is "dimethyl phthalate," while also listing multiple synonyms, including "1,2-benzenedicarboxylic acid, dimethyl ester." You add that both "dimethyl phthalate" and "1,2-benzenedicarboxylic acid, dimethyl ester" are listed in the hazardous substances table in Appendix A to § 172.101 - List of Hazardous Substances and Reportable Quantities with a reportable quantity (RQ) of 5,000 pounds. You ask whether it is permissible to use a synonym or alternate name listed in an SDS as the technical name for a material if the synonym is listed in Appendix A to § 172.101. Additionally, you ask if the synonym is not listed in Appendix A of § 172.101 but is included as another name under the Chemical Abstracts Service (CAS) record, whether it is permissible to use that synonym as the technical name for a hazardous substance in the basic shipping description.

As stated in § 172.203(c) of the HMR, the name of the hazardous substance must be entered in parentheses in association with the basic description when the proper shipping name for a material does not identify the hazardous substance by name. Both "dimethyl phthalate" and "1,2-benzenedicarboxylic acid, dimethyl ester" are listed as hazardous substances in Appendix A to § 172.101 and they are synonyms of the same chemical. As such, it is the opinion of this Office that the proper shipping name could appear as either "UN3082, Environmentally hazardous substance, liquid, n.o.s., 9, III (Dimethyl phthalate)" or "UN3082, Environmentally hazardous substance, liquid, n.o.s., 9, III (1,2-Benzenedicarboxylic acid, dimethyl ester)."

Lastly, § 172.203(c) requires that the name of the hazardous substance listed in Appendix A to § 172.101 appear as the technical name in the basic shipping description if the proper shipping name for a material that is a hazardous substance does not identify the hazardous substance by name. The HMR does not permit the use of a synonym under a CAS record that is not listed in Appendix A to § 172.101 to describe a hazardous substance on shipping papers.

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

Sincerely,

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

172.101, 172.203(c)

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
172.203 Additional description requirements