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Interpretation Response #05-0177 ([AllTranstek LLC] [Mr. James H. Rader])

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

Interpretation Response Details

Response Publish Date:

Company Name: AllTranstek LLC

Individual Name: Mr. James H. Rader

Location State: IL Country: US

View the Interpretation Document

Response text:

Dec 13, 2005


Mr. James H. Rader                        Reference No. 05-0177
Vice President, Technical Support
AllTranstek LLC
1101 31st Street, Suite 200
Downers Grove, IL 605 15-5650

Dear Mr. Rader:

This is in response to your July 12, 2005 letter concerning the applicability of Part 179 of the Hazardous Materials Regulations (HIVIR; 49 CFR Parts 17 1-180) to tank cars. Your questions, and the answers to them, follow:

Q1.      Does § 179.1(a), (b), and (e) limit the applicability of Part 179 to tank cars “marked” only a “DOT specification?

Al.        Before responding directly to this question, several precursor elements must be stated. The “marking” definition in § 171.8 includes a “specification”. . . “required by this subchapter….” This definition in the DOT regulations does not include a requirement that the specification be applied to the car in a particular manner. Applicable language in the Association of American Railroads Tank Car Manual (see Appendix C, 2.0) defines “marking” and “stamping” separately. Both 49 CFR Part 179 and Chapter 3 of the AAR Tank Car Manual require cars to be “marked” per Appendix C of the Manual and “stamped” with the as-built specification and other vital information (See § 179.100-20 and 179.200-24). It is the “stamping” that certifies that the car is built to the specification so indicated. Thus, it is reasonable to conclude, as PHMSA and FRA do, that the marking requirements § 179.1(e), insofar as they relate to the tank specification, and the certification of compliance to that specification, are directed to the stamping of the specification into the head of the tank car and not to the information applied by decal or paint per Appendix C.

Further, the Specifications for AAR Tank Car Tanks set out in Chapter 3 of the Tank Car Manual, state, for instance, that AAR 203W and AAR 211W cars are built in accordance with a referenced DOT specification except as otherwise provided in that chapter. (See Chapter 3, paragraph 3.1.1.) Under § 173.31(a) all tank cars used 1:0 transport a hazardous material must meet the requirements of the specification to which the tank was built. Given the interwoven requirements of the HIVIR, including Part 179, and the AAR Tank Car Manual, it is not possible to say that 179.1(a), (b), and (e) limit Part 179 w only those cars “marked,” i.e., stamped, to a DOT specification. Rather, both the HIVIR and the Tank Car Manual must be read to give the fullest scope and interpretation to each.

Q2.      Given the answer in Question (1) above, do the requirements of Part 179 apply to any tank car constructed and marked to an “AAR” specification, including the limitations on the maximum gross weight on rail at 263,000 pounds?

A2.      As specified in § 179.1(a) Part 179 prescribes the specifications for tanks that …   are to be marked with a DOT specification. As stated in Al, the crucial marking requirement for tank car tanks was the specification stamped into the heads of the tank. Thus, the capacity and gross weight limitations established in § 179.13 (See also § 173.26) apply to tank cars whose tanks are head-stamped with a DOT specification. Conversely, “the weight limitations of § 179.13 do not apply to Class AAR-211W tank cars.” (See paragraph 3.1.1, Chapter 3, AAR Tank Car Manual).

Q3.      Do the requirements of Part 179 apply to tank cars constructed to a “DOT” specification and marked (stenciled) to an “AAR” specification? This is similar to the variable specification plate for highway cargo tanks in § 178.345-1(j) and 178.345-14(e).

A3.      Because the crucial “marking” for the specification of a tank car tank is the head specification and not an alternative specification painted or decaled on the car, a tank car tank stamped with a DOT specification is subject to the requirements of Part 179. There is no railroad tank car analogous to the highway cargo tank “variable specification plate.”

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



Hattie L. Mitchell
Chief, Regulatory Review and Reinvention
Office of Hazardous Materials Standards.

178.345-1, 178.345-14, 179.1

Regulation Sections

Section Subject
178.345-1 General requirements
178.345-14 Marking
179.1 General