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Interpretation Response #15-0077 ([Lawrence Livermore National Laboratory] [Mr. Rod Coleman])

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

Interpretation Response Details

Response Publish Date:

Company Name: Lawrence Livermore National Laboratory

Individual Name: Mr. Rod Coleman

Location State: CA Country: US

View the Interpretation Document

Response text:

October 5, 2015

Mr. Rod Coleman
Lawrence Livermore National Laboratory
7000 East Avenue
Livermore, CA   94550

Ref. No. 15-0077

Dear Mr. Coleman:

This responds to your April 21, 2015 email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-185).  Specifically, you ask for clarification on the classification of the small capsules described in your request, which are each filled with .075 curies (Ci) of tritium gas and present a radioactive hazard as well as a flammable gas hazard (hydrogen).  You also request guidance on how to obtain regulatory relief in order to transport this material by air in the non-Department of Transportation (DOT) specification packaging described in your request.

In your request, you indicate that the shipment of the tritium-filled capsules meets the requirements of the HMR for transport as “UN 2910, Radioactive material, excepted package, limited quantity of material, Class 7.”  However, per the requirements of
§ 173.2a, the flammable gas would be the primary hazard class.  Furthermore, given that                     § 173.306 states that “only packages of hazardous materials authorized aboard passenger-carrying aircraft may be transported as a limited quantity” and “UN1049, Hydrogen, compressed” is forbidden aboard passenger-carrying aircraft, your shipment cannot qualify for limited quantity exceptions and as such, the non-DOT specification packaging you wish to use is not authorized for air transport.

Nevertheless, you state that air transport is needed to make your organization’s project successful, and you believe the small amount of tritium gas contained within the capsules would not sustain a flame if an ignition source was present, as the total combustion energy if all the capsules were burned is only 4 joules (J).  Therefore, you believe the flammable gas would not pose a safety risk during transportation, even when transported in the non-DOT specification packaging exhibited in your request.

Based on the information you provided, it is the opinion of this Office that you should apply to PHMSA for permission to use the non-DOT specification packaging described in your request under the terms of a special permit.  To apply, you must submit an application to the Associate Administrator for Hazardous Materials Safety in conformance with the requirements prescribed in 49 CFR Part 107, Subpart B.  In your application, you must provide justification that the packaging design you are considering achieves a level of safety that is equal to or greater than that required under the HMR.  You may obtain information on the special permit application process from our website at, or by calling PHMSA's Approvals and Permits Division at (202) 366-4511.

I hope this answers your inquiry.  If you need additional assistance, please contact this Office at (202) 366-8553.


Dirk Der Kinderen
Acting Chief, Standards Development Branch
Standards and Rulemaking Division

173.2a, 173.306

Regulation Sections

Section Subject
173.2a Classification of a material having more than one hazard
173.306 Limited quantities of compressed gases