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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 #18-0079

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

Interpretation Response Details

Response Publish Date:

Company Name: Roberts Oxygen Company, Inc.

Individual Name: Robert McHale

Location State: MD Country: US

View the Interpretation Document

Response text:

September 07, 2018

Robert McHale
Roberts Oxygen Company, Inc.
17011 Railroad Street
Gaithersburg, MD 20877

Reference No. 18-0079

Dear Mr. McHale:

This letter is in response to your May 17, 2018, email and letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the requirements for placarding a cargo tank. Specifically, you describe a scenario in which an MC 331 cargo tank motor vehicle (CTMV) is transporting "UN2187, Carbon dioxide, refrigerated liquid" along with cylinders containing hazardous materials. Each side and each end of the CTMV is placarded for each material being transported on the vehicle. The placards are readily visible from each direction they face. However, there are no placards on the cargo tank itself. You ask if the placards must be displayed on the cargo tank.

The answer is no. Affixing placards to the vehicle portion of the CTMV meets the general placarding requirements in § 172.504. Based on your description and the pictures that accompany your request, it is the opinion of this Office that the requirements are met. Furthermore, our response in Letter of Interpretation Ref. No. 10-0126, as referenced in your incoming request, remains valid.

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


Dirk Der Kinderen
Chief, Standards Development Branch
Standards and Rulemaking Division


Regulation Sections

Section Subject
172.504 General placarding requirements