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U.S. Department of Transportation U.S. Department of Transportation Icon United States Department of Transportation United States Department of Transportation

Interpretation Response #03-0062 ([Breed] [Mr. David Gamlen])

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

Interpretation Response Details

Response Publish Date:

Company Name: Breed

Individual Name: Mr. David Gamlen

Location State: FL Country: US

View the Interpretation Document

Response text:

Mar 19, 2003

Mr. David Gamlen                Reference No. 03-0062
Manager, Packaging Engineering
5300 Allen K. Breed Highway
P.O. Box 33050
Lakeland, FL 33807-3050

Dear Mr. Gamlen:

This is in reference to your February 27, 2003 letter concerning the specification requirements in 49 CFR 178.65 for DOT 39 specification non-reusable cylinders and the exemption requirements in DOT-Ell993.  Specifically, you inquired whether a proof pressure test (without determination of expansion) must be performed on the cylinder that is hydrostatically tested to destruction under § 178.65(f)(2). You expressed concern about interrupting the manufacturing line to vent the cylinder and prepare it for the hydrostatic test.

The answer is yes.  Under § 178.65(f), both pressure tests must be performed.  Paragraph (f)(1) requires that each cylinder must be given a proof pressure test; whereas, paragraph (f)(2) requires that one cylinder taken from each designated lot be tested to destruction.

The cylinder taken from the lot be burst tested may meet the leak test and burst test requirements during the same test.  This can be done if the cylinder meets the requirement of § 178.65(f)(1) by being held at test pressure for at least 30 seconds without leaking, and then continues to be pressurized to destruction in accordance with the requirements of § 178.65(f)(2). For DOT-E 11993, the hold time would be 10 seconds instead of 30 seconds.

Most of the other low-pressure cylinder specifications have different requirements.  As an example, the DOT 4B specification in § 178.50(i) requires that one cylinder taken from each designated lot must be given a hydrostatic test with determination of total and permanent volumetric expansions.  All other cylinders must be given a proof pressure test.

I hope this satisfies you inquiry.  Should you have any further questions, please contact this office.



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


Regulation Sections

Section Subject
178.65 Specification 39 non-reusable (non-refillable) cylinders