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Interpretation Response #05-0240 ([Triumvirate Environmental] [Mr. Rick Foote])

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

Interpretation Response Details

Response Publish Date:

Company Name: Triumvirate Environmental

Individual Name: Mr. Rick Foote

Location State: MA Country: US

View the Interpretation Document

Response text:

Nov 30, 2005


Mr. Rick Foote                         Reference No. 05-0240
Sr. Environmental Compliance Advisor
Triumvirate Environmental
61 Inner Belt Road
Somerville, MA 02143

Dear Mr. Foote:

This responds to your September 19, 2005 letter requesting clarification on the classification of rubidium (Rb-87) as a radioactive material under the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180). Specifically, you ask for confirmation that your material, rubidium (Rb-87), is not a hazardous material based on the definition and on activity limits in § 173.433 and 173.436.

According to your letter, your material (Rb-87) is contained within an article, specifically within a small envelope that is part of a measuring device used in GPS system. The activity of the Rb-87 is less than 1.7 x 10 (negative) 4 micro curies (approximately 6.29 becquerels).

Your understanding is correct. The item will not be a Class 7 hazardous material if the total activity of Rb-87 in a consignment is less than 10 million becquerels. In almost all cases, this item will not be a Class 7 hazardous material. It could become a Class 7 hazardous material only if a single consignment were to contain over 1,590,000 of these items, and the activity concentration exceeds 10,000 becquerels per gram.



John A. Gale
Chief, Standards Development
Office of Hazardous Materials Standards

173.433, 173.436

Regulation Sections

Section Subject
173.433 Requirements for determining basic radionuclide values, and for the listing of radionuclides on shipping papers and labels
173.436 Exempt material activity concentrations and exempt consignment activity limits for radionuclides