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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 #09-0184 ([CHS Transportation] [Mr. John Macpherson])

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

Interpretation Response Details

Response Publish Date:

Company Name: CHS Transportation

Individual Name: Mr. John Macpherson

Location State: IA Country: US

View the Interpretation Document

Response text:

December 17, 2009




Mr. John Macpherson

Region Maintenance Manager

CHS Transportation

16682B 245th Street

Mason City, IA 50401

Reference No. 09-0184

Dear Mr. Macpherson:

This is in response to your August 11, 2009 letter concerning placarding requirements under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask if you may use the opposite side of a metal plate mounted on a cargo tank motor vehicle to display the proper shipping name and coordinating placard with UN identification number for "UN 1075, Liquefied petroleum gas (LPG), 2.1 (flammable gas)" and "UN 1005, Ammonia, anhydrous, 2.2 (non-flammable gas)."

According to your letter and the enclosed pictures, you flip the plate to display the appropriate placard and identification number marking for the material in the cargo tank motor vehicle; however, the opposite side showing the placard for the material not in the cargo tank remains visible from certain angles. You ask if this is a violation of § 172.502(a)(1) of the HMR, which prohibits the display of a placard on a packaging, freight container, unit load device, motor vehicle or rail car offered for or transported in commerce unless the placard represents a hazard of the material being transported.

The answer is yes. In the photographs you enclosed, the placards and markings on the sides of the plates facing the vehicle, which do not represent the material contained in the cargo tank, are visible from the road and may confuse a responder to an emergency situation involving one of these vehicles. However, if your company were to cover the interior markings and placard in a way that obscured their view from the road, the plates would conform with § 172.502(a)(1).

I hope this satisfies your request.


Hattie L. Mitchell

Chief, Regulatory Review and Reinvention

Office of Hazardous Materials Standards


Regulation Sections

Section Subject
172.502 Prohibited and permissive placarding