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Interpretation Response #07-0006 ([Sasol North America, Inc.] [Ms. Sheryl Small])

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

Interpretation Response Details

Response Publish Date:

Company Name: Sasol North America, Inc.

Individual Name: Ms. Sheryl Small

Location State: DC Country: US

View the Interpretation Document

Response text:

Feb 6, 2007

Ms. Sheryl Small                                           Reference No. 07-0006

Sasol North America, Inc.

900 Threadneedle, Suite 100

Houston, TX 77079

Dear Ms. Small:

This is in response to your January 3, 2007 letter requesting clarification under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) regarding domestic shipment of Ethyl Acrylate in bulk (by truck or rail). Specifically you ask for guidance on determining whether "Ethyl acrylate, stabilized" is regulated as a marine pollutant under the HMR.

You note in your letter that the proper shipping name "Ethyl acrylate, stabilized" is listed in the § 172.101 Hazardous Materials Table (HMT) but not listed in Appendix B to § 172.101 (List of Marine Pollutants). However, you note that "Ethyl propenoate, inhibited" is in the List of Marine Pollutants and that Ethyl Acrylate and Ethyl Propenoate are chemical synonyms. The difference between the chemical names is the terms "stabilized" and "inhibited."

According to the various chemical indexes, Ethyl Acrylate and Ethyl Propenoate are indeed chemical synonyms. Further, the terms "stabilized" and "inhibited" have the same meaning, that is, both terms are used to describe a material that is in a condition that precludes an uncontrolled reaction (see § 171.8). Under Docket HM-215D (66 FR 33316; June 21, 2001), PHMSA amended all entries in the HMT to replace the term "inhibited" with "stabilized." The use of the term "stabilized" introduced internationally accepted and standardized hazard communication wording and conveys that the addition of a stabilizing compound or other means of stabilization such as temperature control measures have been implemented o prevent an unwanted reaction of a hazardous material.

Therefore, based on the above information, "Ethyl acrylate, stabilized" is regulated as a marine pollutant under the HMR (see § 171.4 and 171.8). Specific to your scenario, bulk transport of "Ethyl acrylate, stabilized" by truck or rail is subject to the requirements for transport of marine pollutants under the HMR.


John A. Gale

Chief, Standards Development

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table