USA Banner

Official US Government Icon

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure Site Icon

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #00-0323 ([Iowa Department of Transportation] [Mr. Tom Sever])

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

Interpretation Response Details

Response Publish Date:

Company Name: Iowa Department of Transportation

Individual Name: Mr. Tom Sever

Location State: IA Country: US

View the Interpretation Document

Response text:

February 15, 2001


Mr. Tom Sever                                                 Ref. No: 00-0323
Iowa Department of Transportation
Motor Vehicle Enforcement
P.O. Box 10473
Des Moines, Iowa 50306-0473

Dear Mr. Sever:

This responds to your November 17, 2000 letter concerning the applicability of the placarding requirements in the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to domestic shipments of Class 9 materials.  Specifically, you disagree with our determination that a Class 9 placard is not required for shipments traveling through the United States that may be intended for destinations outside the United States.

The CLASS 9 placard was included in the HMR to assure consistency with international hazardous materials transportation regulations.  We provided an exception from placarding for shipments of Class 9 materials in domestic transportation because the risks associated with their transportation are relatively low as compared with other classes of hazardous materials, and the communication of the hazard using a placard is not cost-effective.  As stated in a February 25, 1997 letter of clarification on this subject, an international shipment of hazardous material traveling through the United States may benefit from the domestic transportation placarding exception in § 172.504(f)(9) while the material is in the United States.  For safety and hazard communication purposes, there is no difference between a shipment of a Class 9 material being transported entirely within the United States and a shipment of a Class 9 material being transported through the United States to a foreign destination.  Thus, we do not agree that the February 25, 1997 letter of clarification should be rescinded.  Further, because of the need to maintain consistency between the HMR and international standards, we do not agree that the CLASS 9 placard should be eliminated.

You also suggest that we use the same criteria for determining whether a shipment is being transported in interstate or international commerce for purposes of the HMR as the Federal Motor Carrier Safety Administration does in applying the Federal Motor Carrier Safety Regulations (FMCSR).  Determinations as to the applicability of the HMR and FMCSR differ because of differences in the authorizing statutes that form the bases for the hazardous materials and motor carrier safety programs.

I hope this information is helpful.  If you have further questions, please do not hesitate to contact this office.



Edward T. Mazzul1o
Director, Office of Hazardous Materials Standards


Regulation Sections

Section Subject
172.504 General placarding requirements