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Interpretation Response #01-0132 ([CONDEA Vista Company] [Mr.Michael K. Adle])

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

Interpretation Response Details

Response Publish Date:

Company Name: CONDEA Vista Company

Individual Name: Mr.Michael K. Adle

Location State: MD Country: US

View the Interpretation Document

Response text:

June 26, 2001


Mr.Michael K. Adle                           Ref.  No. 01-0132
CONDEA Vista Company
3441 Fairfield Road
Baltimore, MD 21226-1592

Dear Mr. Adle:

This is in response to your May 23, 2001 letter, regarding the attendance requirements for unloading tube trailers and cargo tanks under the Hazardous Materials Regulations (HMR- 49 CFR Parts 171-180).  Specifically, you ask whether attendance requirements as specified in § 177.634(i)(2) apply when a cargo tank or tube trailer is unloaded and the motive power has been removed and taken off the consignee's premises.

The answer is no.  Under § 177.834(i)(2)1, a cargo tank unloading operation need not be attended when the cargo tank has been placed on the consignee's premises and the motive power has been removed from the cargo tank and removed from the premises.  Cylinders permanently mounted on a motor vehicle are commonly referred to as a “tube trailer.” A tube trailer is not considered a cargo tank and therefore is not subject to, the provisions of § 177.834(i) and does not require attendance when being unloaded.

I hope this satisfies your request,



Transportation Regulations Specialist
Office of Hazardous Materials Standards


Regulation Sections

Section Subject
177.834 General requirements