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Interpretation Response #09-0216 ([Ashtead Technology, Inc.] [Mr. Jason Miller])

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

Interpretation Response Details

Response Publish Date:

Company Name: Ashtead Technology, Inc.

Individual Name: Mr. Jason Miller

Location State: TX Country: US

View the Interpretation Document

Response text:

March 31, 2010




Mr. Jason Miller

HSEQ Manager

Ashtead Technology, Inc.

19407 Park Row, STE 170

Houston, Texas 77084

Ref No: 09-0216

Dear Mr. Miller:

This responds to your September 18, 2009 letter regarding the applicability of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to the shipment of compressed hydrogen in non-specification cylinders. Specifically you ask if a material described as "Hydrogen, compressed, 2.1, UN 1049," is excepted from the specification packaging requirements under § 173.306(a)(1) if shipped by highway and cargo aircraft only.

Under § 173.306(a)(1), a compressed gas placed in a non-specification container with a maximum capacity of four fluid ounces (7.22 cubic inches) or less may be described and transported as a limited quantity when it conforms with the provisions of this section. Note that the four fluid ounce (7.22 cubic inches) limit applies to the capacity of the container, not the volume of material contained in the container. This section excepts a limited quantity from labeling, unless offered for transportation by air, and from placarding and specification packaging requirements under the HMR. The HMR permit the shipment of Hydrogen, compressed by highway and cargo aircraft. Under the International Civil Aviation Organization's Technical Instruction for the Safe Transport of Dangerous Goods by Air, compressed hydrogen is authorized for transport aboard cargo aircraft in accordance with packing instruction 200 which permits cylinders other than UN marked and certified cylinders, to be used if the design, construction, testing, approval and markings conform to the requirements of the appropriate national authority in which they are approved and filled.

I hope this satisfies your request.


Hattie L. Mitchell

Chief, Regulatory Review and Reinvention

Office of Hazardous Materials Standards


Regulation Sections

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