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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 #18-0005

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

Interpretation Response Details

Response Publish Date:

Company Name: Commerical Vehicle Safety Alliance

Individual Name: Collin Mooney

Location State: MD Country: US

View the Interpretation Document

Response text:

November 27, 2018

Collin Mooney
Commercial Vehicle Safety Alliance
6303 Ivy Lane, Suite 310
Greenbelt, MD  20770

Reference No. 18-0005

Dear Mr. Mooney:

This letter is in response to your January 5, 2018, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the marking requirements for bulk packagings.

We have paraphrased and answered your questions as follows:

Q1. You ask when identification numbers are required on all four sides of the transport vehicle.

A1. If the identification number marking required by § 172.302(a) for portable tanks, IBCs, and consumer storage containers is not visible, the transport vehicle or freight container used to transport the bulk packaging must be marked on each side and each end as required by § 172.332 with the identification number specified for the material in the § 172.101 Hazardous Materials Table (see §§ 172.326 and 172.331).

Q2. You ask if the marking requirements for a transport vehicle are different for bulk packagings with a capacity of less than 1,000 gallons.

A2. The answer is no. See A1.

Additionally, you are correct in your understanding of the requirement in § 172.330(b) that a motor vehicle used to transport a multi-unit tank car tank containing a hazardous material must be marked on each side and each end regardless of the visibility of the identification number marking on the bulk packaging itself. However, for bulk packagings other than multi-unit tank car tanks, if the identification number marking required by § 172.302(a) is visible no additional identification number markings are required on the transport vehicle.

Q3. You ask if it is the Pipeline and Hazardous Materials Safety Administration's intent that the display of the identification number marking on transport vehicles per 49 CFR, Subpart D be consistent with the placarding requirements in 49 CFR, Subpart F.

A3. The answer is no. Although the requirements for placarding and marking bulk packagings may be similar and resemble consistency, they are two separate requirements 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

172.302(a), 172.332, 172.101, 172.326, 172.331, 172.330(b)

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
172.302 General marking requirements for bulk packagings.
172.326 Portable tanks
172.330 Tank cars and multi-unit tank car tanks
172.331 Bulk packagings other than portable tanks, cargo tanks, tank cars and multi-unit tank car tanks