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Interpretation Response #06-0278

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

Interpretation Response Details

Response Publish Date: 03-29-2007
Company Name: National Transportation Safety Board    Individual Name: Ed B. Dobranetski, P.E.
Location state: DC    Country: US

View the Interpretation Document

Response text:

Mar 29, 2007

Ed B. Dobranetski, P.E.                 Reference No. 06-0278
Senior Civil Engineer
National Transportation Safety Board
490 L’Enfant Plaza, RPH-10
Washington, DC 20594

Dear Mr. Dobranetski:

This is in response to your recent letter to Dr. Robert M. McGuire, former Associate Administrator for Hazardous Materials Safety, Pipeline and Hazardous Materials Safety Administration. YOU ask us to clarify the train placement requirements prescribed in 174.85 of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) for unit trains consisting of placarded amounts of hazardous materials.

Section 174.85(d) specifies requirements for positioning placarded rail cars in a train. For Placard Group 2 materials, including Class 3 materials such as ethanol, this section requires a placarded car to be no nearer than the sixth car from the engine or occupied caboose when train length permits. This requirement applies so long as there are sufficient non-hazardous materials rail cars within the standing train consist to fulfill the requirement. The regulations do not require railroads to change business or operating decisions concerning the number and types of cars placed in the train.

When train length does not permit placement of a placarded car no nearer than the sixth car from the engine or occupied caboose, the placarded car must be placed near the middle of the train, but not nearer than the second car from the engine or occupied caboose. This ensures that placarded tank cars are placed an equal distance from the occupied locomotive and the occupied caboose, thus providing the same level of safety to all crew members

The “middle of the train” requirement applies so long as the caboose is occupied and there are sufficient non-hazardous materials cars available in the train consist, without the railroad having to gather additional cars that may or may not be available or otherwise deviate from normal business practices. However, the almost universal use of a rear end telemetry device in place of a caboose has, for all intents and purposes, rendered the “middle of the train” requirement obsolete, except in those rare instances where the use of an occupied caboose is necessary or required.

If there are not sufficient non-hazardous cars located within the train consist, a is the case for unit trains of tank cars of Placard Group 2 hazardous materials, the loaded placarded tank cars must never be nearer than the second car from the occupied locomotive or occupied caboose.

This is the only federal requirement mandating the addition of non-hazardous cars that may not have been scheduled for the train, since it is a minimum standard for crew protection.

I hope this information is helpful.



Edward T. Mazzullo
Director, Office of Hazardous
    Materials Standards

174.85 (d)

Regulation Sections

Section Subject
§ 174.85 Position in train of placarded cars, transport vehicles, freight containers, and bulk packagings