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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 #11-0076 ([Con-way Freight] [Mr. Keith Jesse Powell])

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

Interpretation Response Details

Response Publish Date:

Company Name: Con-way Freight

Individual Name: Mr. Keith Jesse Powell

Location State: CA Country: US

View the Interpretation Document

Response text:

September 7, 2011




Mr. Keith Jesse Powell

Driver Sales Representative

Con-way Freight

4488 North Cornelia, Apt. 143

Fresno, CA 93722

Reference No. 11-0076

Dear Mr. Powell:

This is in response to your March 31, 2011 e-mail, and April 29, 2011 telephone conversation with a member of my staff requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to placarding. You ask if a transport vehicle, as this term is defined in § 171.8, loaded with one hazardous material that meets the definition of two different hazard classes may use a DANGEROUS placard to represent its secondary hazard class.

In the example you provided, you state different shippers at different facilities load non-bulk packages of "UN 2922, Corrosive, liquids, toxic, n.o.s. (fluorozirconic acid, hydrofluoric acid), 8 (corrosive), 6.1 (poisonous), PG III" on the same transport vehicle, and the total weight of the shipment is 2,205 pounds. You also state the material does not meet the HMR definition for a liquid material that is poisonous by inhalation (see §§ 173.132 and 173.133). You ask if the transport vehicle can display the Class 8 placard for the primary hazard of the material and a DANGEROUS placard for its Division 6.1 subsidiary hazard.

The answer is no. The transport vehicle in your example must be placarded with the CORROSIVE placard. The subsidiary hazard POISON placard may also be displayed (see § 172.505(d)). The HMR permit the DANGEROUS placard to be used in place of the separate placards specified for each Table 2 material listed in § 172.504(e) unless 1,000 kg (2,205 pounds) or more aggregate gross weight of one category of hazardous material in non-bulk packages is loaded at one loading facility. See § 172.504(b). Also, the HMR do not define the term "mixed load." For the purposes of the HMR, it is the opinion of this Office that a mixed load is a shipment of two or more categories of hazardous materials in separate non-bulk packages that require different placards. The shipment in your example

is not a mixed load because it is a "mixture" of two categories of hazardous materials in the same non-bulk package that require the same placard(s).

I hope this satisfies your request.


T. Glenn Foster

Chief, Regulatory Review and Reinvention Branch

Standards and Rulemaking Division

171.8, 172.505, 172.504

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
172.504 General placarding requirements
173.132 Class 6, Division 6.1-Definitions
173.133 Assignment of packing group and hazard zones for Division 6.1 materials