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Interpretation Response #98-0581 ([The Chlorine Institute, Inc.] [Mr. John P. Aherne])

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

Interpretation Response Details

Response Publish Date:

Company Name: The Chlorine Institute, Inc.

Individual Name: Mr. John P. Aherne

Location State: DC Country: US

View the Interpretation Document

Response text:

JUN 3, 1998


Mr. John P. Aherne
Director, Storage and Transport
The Chlorine Institute, Inc.
2001 L Street, NW
Washington, DC 20036-4919

Dear Mr. Aherne:

This is in reference to your letter and a conversation with a member of my staff concerning inspection requirements for cargo tank motor vehicles in 49 CFR Part 180.407. Specifically, you ask for clarity pertaining to the frequency of the internal visual inspection for an Me 331 cargo tank in chlorine
service. You read § 180.407(c) to require performance of the internal visual inspection every five years.

Data available to tins office indicate that chlorine is not corrosive to carbon steel. In the case of a specification MC 331 cargo tank in chlorine service, § 180.407(c) requires performance of a pressure test every two years. Because the pressure test procedure (see § 180.407(g)) calls for an internal visual inspection, also, the five-year retest interval specified in § 180.407(c) is not applicable to specification MC 331 cargo tanks in chlorine service.

If you need further assistance, please contact us.



Thomas G. Allan
Senior Transporation Regulation Specialist
Office of Hazardous Materials Standards

Regulation Sections

Section Subject
180.407 Requirements for test and inspection of specification cargo tanks