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Interpretation Response #21-0087

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

Interpretation Response Details

Response Publish Date:

Company Name: National Institute of Standards and Technology

Individual Name: Mr. Larry Lucas

Location State: MD Country: US

View the Interpretation Document

Response text:

December 8, 2021

Mr. Larry Lucas
National Institute of Standards and Technology
Radiation Physics Division
100 Bureau Drive, Stop 8462
Gaithersburg, MD  20899

Reference No. 21-0087

Dear Mr. Lucas:

This letter is in response to your August 24, 2021, letter requesting clarification of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) applicable to shipping paper requirements for radioactive materials. In your letter, you note that the "Symbol of radionuclide" column of the § 173.435 Table of A1 and A2 values of radionuclides sometimes includes additional information in parenthesis. As an example of this additional information, you cite "U-232 (slow lung absorption)." Specifically, you ask whether the additional information in parenthesis is required to be included on a shipping paper in accordance with § 172.203(d).

The answer is no. As required by § 172.203(d)(1), the description for a shipment of a Class 7 (radioactive) material must include the name of each radionuclide in the Class 7 (radioactive) material that is listed in § 173.435. Based on the example you provided in your letter, it is the opinion of this Office that the additional information in the parenthesis (i.e., slow lung absorption) is not considered part of the radionuclide name (i.e., Uranium or 232U) and therefore, is not required to be indicated on the shipping paper.

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


T. Glenn Foster
Chief, Regulatory Review and Reinvention Branch
Standards and Rulemaking Division

172.203(d), 172.203(d), 173.435

Regulation Sections

Section Subject
172.203 Additional description requirements
173.435 Table of A1 and A2 values for radionuclides