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Interpretation Response #08-0063R ([Disposal Safety Incorporated] [Mr. Steven Amter])

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

Interpretation Response Details

Response Publish Date:

Company Name: Disposal Safety Incorporated

Individual Name: Mr. Steven Amter

Location State: DC Country: US

View the Interpretation Document

Response text:

December 10, 2009




Mr. Steven Amter

Senior Scientist

Disposal Safety Incorporated

1001 Connecticut Avenue, NW, Suite 525

Washington, DC 20036

Reference No. 08-0063R

Dear Mr. Amter:

This letter clarifies my May 16, 2008 response and is in further reference to your

March 7, 2008 letter and your March 14, 26, and April 8, 2008 telephone conversations with a member of my staff concerning a tank car that contains ortho-Toluidine (o-Toluidine). You asked if a warning label or sign may be placed near the tank car's unloading outlet under the Hazardous Materials Regulations (HMR), 49 CFR Parts 171-180). You stated the image of the sign or label had not been determined, but would likely take the shape of a circle, square, or rectangle.

Ortho-toluidine is listed as "UN1708, Toluidines, 6.1, PG II," in the Hazardous Materials Table, § 172.101 in the HMR. The material is also listed as o-Toluidine in Table 1 to Appendix A in § 172.101 and is regulated as a hazardous substance, as defined in § 171.8, when the quantity of o-Toluidine in one package equals or exceeds its reportable quantity (RQ) value of 100 pounds. If the quantity of material being transported in one package meets or exceeds the RQ for o-Toluidine, the letters "RQ" must be included either before or after the basic description on the shipping paper. When transported in a tank car, the tank must be marked on each side and each end with the identification number "1708" in accordance with §§ 172.330(a)(1)(i) and 172.332.

Provided the proposed sign or label by its color, design, shape, or content cannot be confused with and does not conflict with a marking, label or placard prescribed in the HMR, the placement of a label or sign near a tank car's unloading outlet is not prohibited under the DOT regulations. See the requirements in §§ 172.304(a)(4), 172.401(b), and 172.502(a)(2). A sign or label on a tank car must also comply with the tank car marking requirements in Appendix C of the Association of American Railroads Specifications for Tank Cars, which the HMR incorporates by reference in § 171.7. See § 179.22(a). The purpose of this latter requirement is to ensure that all tank car markings, including those required under the HMR, are placed in a location that is consistent with the markings on other tank cars. This consistency makes it easier for railroad and emergency response personnel to identify a tank car in transport.

Although you submitted the proposed text of the label in your inquiry, this Office assessed the content of the label only to determine whether it would conflict with labeling requirements under the HMR. Thus, our May 16, 2008 letter is in no way an endorsement, ratification, or confirmation of the truth of the statements on your label. Moreover, PHMSA does not have the authority or the expertise to determine whether a material is a cancer-causing agent, and no such determination was intended by our letter.

I hope this satisfies your request.


Hattie L. Mitchell

Chief, Regulatory Review and Reinvention

Office of Hazardous Materials Standards

172.101, 172.502, 179.22(a)

Regulation Sections

Section Subject
172.101 Purpose and use of hazardous materials table
172.330 Tank cars and multi-unit tank car tanks
179.22 Marking