U.S. Nuclear Regulatory Commission

Licensing of Depleted Uranium Shielding for Use in Possessing of Mo-99 / Tc-9 9m Generator

HPPOS-191 PDR-9111210302

Title: Licensing of Depleted Uranium Shielding for Use in

Possessing of Mo-99 / Tc-99m Generator

See the letter from V. L. Miller to All Medical Licensees

and Commercial Nuclear Pharmacies dated January 9, 1986.

This letter states that depleted uranium associated with

Mo-99 / Tc-99m generators is exempt from licensing

requirements under 10 CFR 40.13 only when it is used as a

shipping container. A specific license from NRC is needed

to possess and use the depleted uranium as a shield.

Many of the addressees of this letter were authorized to

possess and use Mo-99 / Tc-99m generators ranging in activity

from 200 millicuries to 16 curies of Mo-99. Although most

generators are surrounded by lead shielding, some with

Mo-99 activity greater than 4 curies are surrounded by

depleted uranium first used as a shipping container and

then, upon receipt, as shielding.

The NRC regulations covering depleted uranium are found in

10 CFR Part 40 and include revised provisions that became

effective December 24, 1981. The view of NRC is that

depleted uranium associated with Mo-99 / Tc-99m generators is

exempted from licensing requirements [10 CFR 40.13 (c) (6)]

only when it is used as a shipping container (e.g., when

the generator is in transit from the manufacturer). A

specific license or authorization from NRC is needed to

possess and use the depleted uranium as a shield (e.g.,

during the time the Mo-99 / Tc-99m generators are stored or

used by medical licensees or commercial nuclear

pharmacies). Many licensee facilities using high activity

Mo-99 / Tc-99m generators do not have specific authorization

from NRC to possess and use the depleted uranium as a

shield.

The following license condition must be contained in or

added to the license:

"Pursuant to Title 10, Chapter 1, Code of Federal

Regulations, Part 40, 'Domestic Licensing of Source

Material,' the licensee is authorized to possess, use,

transfer, and import up to 999 kilograms of depleted

uranium contained as shielding material in the

molybdenum-99 / technetium-99m generators authorized by this

license."

The absence of this condition on the licensees current

license is not a health and safety problem and will not be

considered an item of noncompliance. The next time the

license is amended, NRC will formally add this condition to

licenses authorizing possession and use of 4 curies or more

of Mo-99 / Tc-99m generators. Amendments to increase

generator possession limits to 4 curies or more will also

include this license condition.

Regulatory references: 10 CFR 40.13

Subject codes: 11.1, 11.6

Applicability: Source Material