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Interpretation Response #10-0210 ([Cryofab, Inc.] [Mr. Greg Grillo])

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

Interpretation Response Details

Response Publish Date:

Company Name: Cryofab, Inc.

Individual Name: Mr. Greg Grillo

Location State: NJ Country: US

View the Interpretation Document

Response text:

December 15, 2010



Mr. Greg Grillo

Cryofab, Inc.

540 N. Michigan Ave.

Kenilworth, NJ 07033

Reference No.: 10-0210

Dear Mr. Grillo:

This is in response to your October 6, 2010 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the transportation of liquid helium by aircraft. Specifically, you ask if cylinders and packagings that are authorized by the HMR under § 173.320 for highway and rail transport are also authorized for air transport by the appropriate national authority, the United States Department of Transportation.

The general requirements for cryogenic liquids in cylinders are found in § 173.316 and require cryogenic liquids to be transported in specification DOT-4L cylinders. In addition to these requirements, packaging exceptions for cryogenic liquids are found in § 173.320 and allow for alternative packaging methods. Section 173.320 specifies that atmospheric gases (e.g., oxygen, nitrogen, carbon dioxide) and helium in Dewar flasks, insulated cylinders, insulated portable tanks, insulated cargo tanks, and insulated tank cars, designed and constructed so that the pressure in such packagings will not exceed 25.3 psig under ambient conditions during transportation are not subject to the requirements of the HMR when transported by motor vehicle or railcar except as specified in paragraphs (a)(1), (a)(2), and (a)(3) of this section.

As stated in § 173.320(c), for transportation aboard aircraft, the HMR requires cryogenic liquids to be packaged in accordance with the International Civil Aviation Organization (ICAO) Technical Instructions, Packing Instruction 202 and the packaging specifications in part 6, chapter 5. The ICAO Technical Instructions section authorized a cryogenic liquid, such as helium, to be transported in packages not in compliance with UN specifications if approved by the appropriate national authority in the countries of transport and use. Therefore, if the requirements in the ICAO Technical Instructions that are referenced in § 173.320(c) cannot be met, an approval would be required to transport atmospheric gases (e.g., oxygen, nitrogen,

carbon dioxide) and helium in Dewar flasks, insulated cylinders, insulated portable tanks, insulated cargo tanks, and insulated tank cars via air in accordance with the HMR. The procedures to apply for an approval are specified in 49 CFR § 107.705.

I hope this satisfies your inquiry. Please contact us if we can be of further assistance.


T. Glenn Foster

Chief, Regulatory Review and Reinvention Branch

Standards and Rulemaking Division

173.320, 173.316

Regulation Sections

Section Subject
173.316 Cryogenic liquids in cylinders
173.320 Cryogenic liquids; exceptions