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Interpretation Response #10-0101 ([Jefferson Lab Thomas Jefferson National Accelerator Facility] [Mr. Thomas Briggs, PE])

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

Interpretation Response Details

Response Publish Date:

Company Name: Jefferson Lab Thomas Jefferson National Accelerator Facility

Individual Name: Mr. Thomas Briggs, PE

Location State: VA Country: US

View the Interpretation Document

Response text:

June 14, 2010




Mr. Thomas Briggs, PE

Property Manager

Jefferson Lab

Thomas Jefferson National

Accelerator Facility

628 Hofstadter Road, Suite #1

Newport News, VA 23606

Ref. No. 10-0101

Dear Mr. Briggs:

This responds to your April 22, 2010, letter regarding the Materials of Trade (MOT) exception in

§ 173.6 of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) as it applies to the transportation of a small quantity of liquid nitrogen in a 10 liter Dewar, for use in science related demonstrations.

According to your letter, the Thomas Jefferson National Accelerator Facility is a contractor operated Department of Energy Laboratory. To encourage interest in science, the Laboratory's teaching staff visits local schools providing science related lectures and demonstrations. Several of the demonstrations require transporting a small quantity of liquid nitrogen in a 10 liter Dewar secured in the back of an open pickup truck. Specifically, you ask whether the MOT's exception in § 173.6 for Division 2.1 or 2.2 materials cover the transport of liquid nitrogen in a small portable Dewar?

Section 173.6 contains provisions for certain hazardous materials meeting the definition of Materials of Trade, as defined in § 171.8. MOTs that are being transported by motor vehicle are not subject to any other requirements of the HMR except those stipulated in § 173.6. The MOT's exception in § 173.6(a)(2) may be used to transport a Division 2.1 (flammable gas) or 2.2 (non-flammable gas) material, such as liquid nitrogen, in a small 10 liter portable Dewar flask.

However, a cryogenic liquid, such as liquid nitrogen in Dewar flasks designed and constructed so that the pressure in such packaging will not exceed 25.3 psig under ambient temperature conditions

is not subject to the requirements of the HMR when transported by motor vehicle or railcar, except as specified in § 173.320 (a)(1), (a)(2), and (a)(3).

I hope this information is helpful. If we can be of further assistance, please contact us.


Charles E. Betts

Chief, Standards Division

Office of Hazardous Materials Standards

173.6, 173.320, 171.8

Regulation Sections

Section Subject
171.8 Definitions and abbreviations
173.320 Cryogenic liquids; exceptions
173.6 Materials of trade exceptions