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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 #19-0115

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

Interpretation Response Details

Response Publish Date:

Company Name: McAnally Wilkins Inc.

Individual Name: Ray Miller

Location State: TX Country: US

View the Interpretation Document

Response text:

January 09, 2020

Ray Miller
McAnally Wilkins Inc.
110 W. Louisiana, Suite 150
Midland, TX  79701

Reference No. 19-0115

Dear Mr. Miller:

This letter is in response to your September 23, 2019, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to prohibited placarding. You explain that it is a common industry practice when transporting frac sand to designate the shipping containers with a solid colored square that communicates the grade of sand only. You further explain that these squares come in various solid colors (e.g., blue, red, etc.) and do not communicate hazard classifications (e.g., Class 3 "Flammable Liquid" or Class 4 "Dangerous When Wet"). Specifically, you seek confirmation of your understanding that the colored squares alone are not prohibited by § 172.502(a)(2) and that the vehicles are not subject to the HMR since they do not transport any hazardous materials, specification packages, or provide any hazard communication.

Your understanding is correct. Based on the photographs you provided, the solid colored squares would not be prohibited by the HMR. Although they have similar colors to placards subject to the HMR, the square display (i.e., not "square-on-point") and lack of content is different from the hazardous materials placard and would not be confused with prescribed placards in the HMR.

Please note that in accordance with § 172.502(a)(2), no person may affix or display on a freight container any sign, advertisement, slogan (such as "Drive Safely"), or device that, by its color, design, shape or content, could be confused with any placard prescribed in the HMR.

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
172.502 Prohibited and permissive placarding