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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 #18-0133

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

Interpretation Response Details

Response Publish Date:

Company Name: The Sulphur Institute

Individual Name: Mr. Craig Jorgenson

Location State: DC Country: US

View the Interpretation Document

Response text:

March 06, 2019

Mr. Craig Jorgenson
Vice President, Transportation and Regulatory Affairs
The Sulphur Institute
1020 19th Street NW, Suite 520
Washington, DC  20036

Reference No. 18-0133

Dear Mr. Jorgenson:

This letter is in response to your October 22, 2018, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the use of alternative spellings for proper shipping names as outlined in § 172.101(c)(1).  You seek to clarify that the alternate spellings apply to Subparts A through I, and are inclusive of Appendices A through D in Part 172 and all parts of Subchapter C.  Specifically, you ask if “sulfur” and “sulphur” are equally acceptable spellings for use on shipping papers, labels, and markings for hazardous materials packages. 

The answer to your question is yes, so long as whichever alternative spelling is used to identify the hazardous material, is used consistently.  Section 172.101(c)(1) states that words may be alternatively spelled in the same manner as they appear in the International Civil Aviation Organization (ICAO) Technical Instructions for the Safe Transport of Dangerous Goods by Air or the International Maritime Dangerous Goods (IMDG) Code, and provides the example that “sulfur” may be spelled “sulphur.”  These instructions for the purpose and scope of the Hazardous Materials Table (HMT; § 172.101) serve as the basis for all hazardous materials communication in Part 172, to include shipping papers, marking, labeling, and placarding.  Even though the specific example of “sulphur” as an alternative spelling to “sulfur” is not continually used throughout the HMR—including in the bulk packaging marking requirements for elevated temperature materials in § 172.325(b)—these alternative spellings are recognized for all hazardous materials communications. 

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


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

172.101(c)(1), 172.101, 172.325(b)

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
172.325 Elevated temperature materials