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Interpretation Response #24-0029

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

Interpretation Response Details

Response Publish Date:

Company Name: Richard Bonomo

Individual Name: Clandestine Materials Detection Inc.

Location State: WI Country: US

View the Interpretation Document

Response text:

December 4, 2024

Richard Bonomo
Engineer and Laboratory Manager
Clandestine Materials Detection Inc.
2555 Industrial Dr.
Monona, WI  53713

Reference No. 24-0029

Dear Mr. Bonomo:

This letter is in response to your May 16, 2024, email requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to the classification of an explosive detection system utilizing deuterium. Specifically, you state that you are seeking clarification on the classification of a device designed to detect explosives using deuterium (UN1957, Division 2.1 flammable gas) at a pressure of approximately 50 mTorr (0.0000658 atmosphere).

PHMSA regulates the transportation in commerce of materials it determines are hazardous in that "the amount and form [of the material] may pose an unreasonable risk to health and safety or property." 49 U.S.C 5103, as delegated to PHMSA in 49 C.F.R 1.53(b). Based on the information provided in your email, even in the event of a release, the low quantity of deuterium in your device, calculated based on the pressure and size of the container, would not support combustion due to the ratio of air to deuterium. Based on the information you provided the deuterium is not in a quantity and form that pose an unreasonable risk to health, safety or property during transportation and, therefore, are not subject to regulation under the HMR.

I hope this information is helpful. Please contact us if we can be of further assistance.

Sincerely,

Alexander Wolcott
Acting Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

Regulation Sections