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Interpretation Response #09-0148 ([Mr. Peter Collins] [U.S. Department of Justice Federal Bureau of Prisons])

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

Interpretation Response Details

Response Publish Date:

Company Name: Mr. Peter Collins

Individual Name: U.S. Department of Justice Federal Bureau of Prisons

Location State: DC Country: US

View the Interpretation Document

Response text:

August 7, 2009




Mr. Peter Collins

U.S. Department of Justice

Federal Bureau of Prisons

320 First Street, NW

Washington, DC 20534

Reference No. 09-0148

Dear Mr. Collins:

This is in response to your August 19, 2004 letter, postmarked June 17, 2009, and your

June 29, 2009 telephone conversation with Ms. Eileen Edmonson of my staff concerning requalifying cylinders under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask whether a cylinder filled before its requalification date may remain in storage and be transported off-site for use for an indefinite period of time after this date.

The answer is yes. Under the HMR, a cylinder filled (i.e., charged) before its requalification becomes due may remain in service until it is emptied, and may be transported in commerce by highway, rail, aircraft, or vessel provided the cylinder is in sound condition and all applicable HMR requirements are met (see §§ 171.2, 173.301(a)(6), and 180.205). A DOT specification cylinder containing a hazardous material need not be emptied to meet a testing schedule under the HMR but may be required for cylinders used in certain applications by some other Federal agency. A cylinder past its test date may not be filled or topped off with a hazardous material and transported in commerce. After emptying, a cylinder due for retest may not be refilled and offered for transportation unless it has been inspected and retested in accordance with Part 180, Subpart C of the HMR. However, a cylinder with a specified service life may not be refilled and offered for transportation after its authorized service life has expired (see §§ 173.301(a)(7) and 180.205(c)).

You also ask how the wording "remain in service" is defined under the HMR. The HMR do not define this phrase; however, as this phrase is used in the HMR, it means the cylinder may be used to transport the product it contains until the cylinder is emptied, provided the cylinder continues to meet all applicable requirements.

I hope this satisfies your request.


Hattie L. Mitchell

Chief, Regulatory Review and Reinvention

Office of Hazardous Materials Standards

173.301(a)(6), 180.205(a), 171.2



Regulation Sections

Section Subject
171.2 General requirements
173.301 General requirements for shipment of compressed gases and other hazardous materials in cylinders, UN pressure receptacles and spherical pressure vessels