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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 #21-0086

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

Interpretation Response Details

Response Publish Date:

Company Name: OMG Inc.

Individual Name: Bradley Bedard

Location State: MA Country: US

View the Interpretation Document

Response text:

October 21, 2021

Mr. Bradley Bedard
VP Supply Chain Management
OMG Inc.
153 Bowles Road
Agawam, MA  01001

Reference No. 21-0086

Dear Mr. Bedard:

This letter is in response to your August 19, 2021, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to cylinder marking requirements. In your email, you included photographs depicting a Department of Transportation (DOT) specification 39 (DOT 39) cylinder that is marked with a space between the “M” and the numerals instead of before the "M."  You ask whether the additional space is a violation of the HMR.

Section 178.65(i)(2)(v) specifies that a DOT 39 cylinder must be marked with the registration number (M****) of the manufacturer. The addition of the space between the "M" and the numerals is not a violation of § 178.65(i). However, the markings as depicted in your photograph may frustrate the transportation of the cylinders.

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

178.65(i)(2)(v), 178.65(i)

Regulation Sections

Section Subject
178.65 Specification 39 non-reusable (non-refillable) cylinders