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Interpretation Response #08-0098 ([HazMat Resources, Inc.] [Mr. Danny Shelton])

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

Interpretation Response Details

Response Publish Date:

Company Name: HazMat Resources, Inc.

Individual Name: Mr. Danny Shelton

Location State: NC Country: US

View the Interpretation Document

Response text:

August 5, 2008






Mr. Danny Shelton

Vice President, Business Development

HazMat Resources, Inc.

10104 Creedmoor Road

Raleigh, NC  27615


Ref. No. 08-0098


Dear Mr. Shelton:


This is in response to your letter dated April 17, 2008, requesting clarification of §§ 172.504 and 172.516 of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180).  Specifically, you ask whether the display of a placard in a placard holder mounted clear of obstructions on the fender of a cargo tank motor vehicle facing the front or rear of the transport vehicle satisfies the requirements of §§ 172.504 and 172.516.  You reference previous letters of clarification dated August 6, 2004 from John Gale to Charles Phillips (Ref. No. 04-0164) and May 6, 1999 from Delmer Billings to Bruce Bugg (Ref. No. 99-0048) and provide several photos.  You indicate that the letters conflict with one another. 


When placarding is required by § 172.504(a) of the HMR, a transport vehicle must be placarded on each side and each end.  The HMR require a placard to be clearly visible from the direction it faces, except from the direction of another transport vehicle to which it is coupled (see § 172.516(a)).  For purposes of the HMR, a "transport vehicle" is a cargo-carrying vehicle, such as a van, tractor, trailer, semi-trailer, tank car, or rail car used for the transportation of cargo by any mode.  Each cargo-carrying body is a separate transport vehicle.  In accordance with § 171.8, a transport vehicle with no intermediate form of containment meets the definition of a bulk packaging.


We have reviewed the letters and the photos you submitted.  The photos you provided are of placards mounted on the front or rear end of semi-trailers used in a truck-tractor/trailer configuration.  The letters you reference were provided by this office in response to very specific placarding questions.  Letter 04-0164 addresses the display of placards on a single transport vehicle (e.g., straight truck) as follows:


"Each placard on a motor vehicle must be visible from the direction it faces, except from the direction of "another transport vehicle" to which the motor vehicle is coupled (172.516).  In this case, the truck-tractor is not "another transport vehicle," because it is part of a single transport vehicle.  Therefore, the obscured placard does not meet the visibility requirement in § 172.516.  A placard placed on the front of the truck-tractor in accordance with § 172.516(b) would satisfy the visibility requirement of § 172.516(a)."


Letter 99-0048 addresses two or more transport vehicles used in combination (e.g., truck-tractor/semi trailer) as follows:


"Section 172.504 states that a transport vehicle must be placarded on each side and each end.  A placard located on the tank fender that "faces" the front of the tank is not "on" the front end, and therefore, the placard does not comply with 172.504.  Additionally, the location of the placard does not satisfy the visibility requirements of 172.516(a)."


The letters do not conflict, as you suggest.  However, though the intent of letter 99-0048 was to prohibit front and rear placards that are not actually on the end of the transport vehicle, the language in the letter actually implies that the front and rear placards cannot be on the fenders even if they are on the end of the transport vehicle.  Placards that are on the end of the bulk package, which includes a transport vehicle that has no intermediate form of containment, may be used to meet the requirements in §§ 172.504(a) and 172.516(a).


Therefore, this letter clarifies that in the truck-tractor/trailer configuration that you describe, a forward or rear facing placard, mounted so that its plane is substantially perpendicular to the longitudinal axis of the vehicle, may be on the fender as long as it is visibly mounted on the end of the transport vehicle.  You should also note, when the front of a transport vehicle is blocked by another transport vehicle (e.g., the truck tractor blocks the front of the semi-trailer) it is our opinion that mounting a placard on the front of the truck-tractor in accordance with § 172.516(b) is the most effective means of satisfying the visibility requirements in § 172.516(a).


I hope this satisfies your inquiry.  If we can be of further assistance, please contact us.






Edward T. Mazzullo


Office of Hazardous Materials Standards


172.504, 172.516

Regulation Sections

Section Subject
172.504 General placarding requirements
172.516 Visibility and display of placards