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Interpretation Response #11-0036 ([Cusco Fabricators, Inc.] [Mr. Sarathi Chilukuri])

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

Interpretation Response Details

Response Publish Date:

Company Name: Cusco Fabricators, Inc.

Individual Name: Mr. Sarathi Chilukuri

Country: CA

View the Interpretation Document

Response text:

May 25, 2011



Mr. Sarathi Chilukuri

Cusco Fabricators, Inc.

305 Enford Road

Richmond Hill, ON L4C 3E9


Reference No.: 11-0036

Dear Mr. Chilukuri:

This responds to your email concerning the definition of a "Portable Tank" as defined by the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask if the roll-on/roll-off units you describe in your letter can be defined as portable tanks under the HMR.

In your letter you describe your roll-on/roll-off units as tanks that can be moved on and off of a truck chassis or trailer bed using a detachable lifting system. These units you describe are equipped with a hoisting system that utilizes chains and binding straps to move the unit. These units are not permanently attached to any mobile system. Based on the description you provided for your roll-on/roll-off units, these units appear to meet the definition of a portable tank. However, in your letter you also state that it is a widespread industry practice to build and certify these roll-on/roll-off units to DOT 407 and DOT 412 specifications. It should be noted that DOT 407 and DOT 412 are specifications for cargo tanks therefore, if the units you describe are built to these specifications they are considered a cargo tank.

As specified in § 171.8, a portable tank means a bulk packaging (except a cylinder having a water capacity of 1,000 pounds or less) designed primarily to be loaded onto, or on, or temporarily attached to a transport vehicle or ship and equipped with skids, mountings, or accessories to facilitate handling of the tank by mechanical means. It does not include a cargo tank, tank car, multi-unit tank car tank, or trailer carrying 3AX, 3AAX, or 3T cylinders.

The specifications for portable tanks are found in Subpart H of Part 178 of the HMR. Portable tanks not meeting a specification found in Subpart H of Part 178 of the HMR would be considered a non-specification bulk container. In accordance with §173.22(a)(2) it is the shipper"s responsibility to determine that the packaging or container to be used is an authorized packaging, including part 173 requirements, and that it has been manufactured, assembled, and marked in accordance with part 178.

I hope this satisfies your inquiry. Please contact us if we can be of further assistance.


T. Glenn Foster

Chief, Regulatory Review and Reinvention Branch

Standards and Rulemaking Division

178. Subpart H, 173.22, 171.8

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
173.22 Shipper's responsibility