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Interpretation Response #07-0210 ([University of California, Los Angeles] [Ms. Carol S. Marcus])

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

Interpretation Response Details

Response Publish Date:

Company Name: University of California, Los Angeles

Individual Name: Ms. Carol S. Marcus

Location State: CA Country: US

View the Interpretation Document

Response text:

January 30, 2008

Ms. Carol S. Marcus

Professor of Radiation Oncology and of Radiological Sciences, UCLA

1877 Comstock Avenue

Los Angeles, CA 90025-5014

Ref No.: 07-0210

Dear Ms. Marcus:

The Pipeline and Hazardous Materials Safety Administration (PHMSA) is issuing this letter to clarify the applicability of the Hazardous Materials Regulations (HMR; 49 CFR Parts 171-180) to the transportation of check sources used in radiation detection devices. On December 17, 2006 you sent a letter requesting a policy statement from the Transportation Security Administration (TSA) regarding the carriage of radiation detection devices and check sources on commercial aircraft. In that letter you described the check sources as tiny quantities of radioactive material in the form of sealed sources which are used to check that survey meters are working properly. You state that the check sources are so low in activity that they fall under the Nuclear Regulatory Commission (NRC) category of exempt material. On January 22, 2007, TSA issued a letter responding to your request. We are issuing this letter to clarify the applicability of the HMR to the transportation of check sources. The HMR must be considered in addition to TSA restrictions when transporting hazardous materials by aircraft.

Your letter to TSA does not indicate type, quantity, or activity of the radioactive material. However, your check source is not subject to the HMR if: (1) the activity concentration in each device is below the activity concentration limit for exempt material specified in § 173.436 for the radionuclide; or, (2) the total activity of the consignment (all devices being carried) is less than the activity limit for exempt consignment specified in § 173.436 for the radionuclide. If the activity exceeds both of these exempt limits, then the device may be offered for transportation as a "Radioactive material, excepted package-limited quantity of material" or "Radioactive material, excepted package-instrument" (for a check source carried in the survey meter) if it satisfies the conditions in §§ 173.421 or 173.424, and § 173.422. Note that the exception requires training in accordance with Subpart H of Part 172. In addition, the outside of each package must be marked with the UN identification number (UN2910 or UN2911) when transporting radioactive material in accordance with §§ 173.421 or 173.424, and § 173.422.

It should be noted that the International Civil Aviation Organization"s Technical Instructions for the Safe Transport of Dangerous Goods (ICAO TI) specifically prohibits passengers from carrying excepted radioactive materials in the cabin or in checked baggage (see ICAO TI 8; 1.1.1). Many commercial airlines follow the International Air Transport Association"s (IATA) Dangerous Goods Regulations which are based on the ICAO TI. Therefore, even in the U.S., airlines may choose to prohibit the carriage of excepted radioactive materials in the cabin and checked baggage based on these ICAO international regulations or IATA industry standards.

In addition, a U.S. air operator"s ability to carry excepted radioactive materials may also be limited by its operations specifications issued by the Federal Aviation Administration (FAA).

I hope this information is helpful. If you have further questions, please do not hesitate to contact this office.


Edward T. Mazzullo

Director, Office of Hazardous Materials Standards

175.10, 173.436

Regulation Sections

Section Subject
173.436 Exempt material activity concentrations and exempt consignment activity limits for radionuclides
175.10 Exceptions for passengers, crewmembers, and air operators