Equivalency and Exceptions

DOE-STD-3028-2000

Although disposition of 233U is part of the planned activities for DOE's fissile materials

disposition program, it is recognized that various factors could potentially delay disposition. Fifty

years is selected as a reasonable upper time limit that material might have to be stored because

of such delays.

A.2

EQUIVALENCY AND EXCEPTIONS

The basis for equivalency shall be a technical justification for any departure from specific

provisions of the Standard. This technical justification will be subject to oversight by the

authorizing official.

A.3

APPLICABILITY

No further basis provided.

A.4

REFERENCES

No further basis provided.

A.5

ACRONYMS AND DEFINITIONS

No further basis provided.

A.6

PACKAGING, AND STORAGE CRITERIA

A.6.1

Materials

A.6.1.1

Uranium-233 Metals

1. Potentially pyrophoric metals are not acceptable storage forms because this could

lead to fires and dispersal of the uranium. Uranium metal in massive form presents

little fire hazard, but it will burn if exposed to a severe, prolonged fire. By contrast,

finely divided uranium metal powder is pyrophoric [Bretherick 1986], and can ignite

spontaneously, even if confined in a container without liquid or without air movement.

The presence of moisture in the gas phase over exposed chips increases this

possibility [Totemeier 1995]. The flammability of uranium metal depends almost

entirely on its specific surface area. Finely divided uranium metal ignites

spontaneously upon exposure to air and burns rapidly to form an oxide. For uranium

foils and wires, the experimentally determined ignition temperatures are somewhat

higher than for powders having the same specific surface area. The specific surface