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Interpretation Response #08-0010 ([D.B. Western, Inc. - Texas] [Mr. Phil Johnson])

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

Interpretation Response Details

Response Publish Date:

Company Name: D.B. Western, Inc. - Texas

Individual Name: Mr. Phil Johnson

Location State: TX Country: US

View the Interpretation Document

Response text:

March 5, 2008


Mr. Phil Johnson

D.B. Western, Inc. - Texas

12511 Strang Road

LaPorte, TX 77572

Ref. No. 08-0010

Dear Mr. Johnson:

This is in response to your December 26, 2007 letter to Mr. Don Burger of the Pipeline and Hazardous Materials Safety Administration"s (PHMSA"s) Office of Hazardous Materials Special Permits and Approvals, and January 9, 2008 telephone conversation with a member of my staff concerning the shipment of a flammable liquid in a 286,000-pound rated tank car under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Your letter was forwarded to PHMSA"s Office of Hazardous Materials Standards for reply.

You state your company, a chemical manufacturer, plans to move its plant to a new location and would like to use a 286,000 pound, gross weight limitation (GWL) rated tank car to transport a new product it is developing with a high methanol content that may meet the definition of a flammable liquid. We have paraphrased your questions and answered them in the order posed in your letter.

Q1. If a flammable liquid product is shipped in a 286,000-pound rated tank car, is it correct that the use of a Class DOT-111 tank car must be authorized by PHMSA under the terms of a special permit?

A1. Assuming your product is a Class 3 (flammable liquid), PG II material, § 173.242 of the HMR authorizes the use of Class DOT-103, DOT-104, DOT-105, DOT-109, DOT-111, DOT-112, DOT-114, DOT-115, and DOT-120 tank cars. Of these tank cars, Class DOT-105, DOT-111, and DOT-112 tank cars of the requested weight have been authorized for use under the terms of a PHMSA-issued special permit. Please note that § 179.13 requires that any tank cars built after November 30, 1970, must not exceed 34,500 gallons capacity or 263,000 pounds gross weight on rail. Any deviation from these limitations must be authorized under the terms of a special permit issued by the Associate Administrator for Hazardous Materials Safety, PHMSA.

Q2. What is this permit called and where do we locate the information on how to apply for it and what it costs?

A2. A "special permit" is defined in § 171.8 and its requirements are prescribed in 49 CFR Part 107, Subpart B. The application procedures are prescribed in § 107.105. An applicant must submit an application and supporting documentation, as well as any additional information or materials we request to process the application. This agency does not charge any processing fees for special permits.

Q3. What are the limits for what is considered a flammable liquid and what is not?

A3. The defining criteria for a Class 3 (flammable liquid) material are prescribed in § 173.120(a) and are as follows:

" A liquid having a flashpoint of not more than 60 ºC (140 ºF), or

" Any material in a liquid phase with a flash point at or above 37.8 ºC (100 ºF) that is intentionally heated and offered for transportation at or above its flash point in a bulk packaging.

A combustible liquid is also a Class 3 material. Its defining criteria are prescribed in § 173.120(b) and are as follows:

" Any liquid that does not meet the definition of any other hazard class specified in the HMR and has a flash point above 60 ºC (140 ºF) and below 93 ºC (200 ºF).

" A flammable liquid with a flash point at or above 38 ºC (100 ºF) that does not meet the definition of any other hazard class may be reclassed as a combustible liquid. This provision does not apply to transportation by vessel or aircraft, except where other means of transportation are impractical. An elevated temperature material that meets the definition of a Class 3 material because it is intentionally heated and offered for transportation or transported at or above its flash point may not be reclassed as a combustible liquid.

" A combustible liquid that does not sustain combustion when tested using either test method specified in American Society for Testing and Materials (ASTM) standard D 4206 (see § 171.7), or the procedure in Appendix H of 49 CFR Part 173 when heated under test conditions and exposed to an external flame source, is not subject to the HMR as a combustible liquid.

Additional requirements for classifying or excepting a material as a flammable liquid are prescribed in §§ 173.120 and 173.150, and the requirements for assigning a Packing Group to a flammable liquid are prescribed in § 173.121.

I hope this satisfies your request.


Hattie L. Mitchell, Chief

Regulatory Review and Reinvention

Office of Hazardous Materials Standards

179.13 173.120 173.242

Regulation Sections

Section Subject
173.120 Class 3-Definitions
173.150 Exceptions for Class 3 (flammable and combustible liquids)
179.13 Tank car capacity and gross weight limitation