Radiological Safety Training for Uranium Facilities
Module 101 - Properties of Uranium
Uranyl compounds, such as uranyl nitrate, or UO 2(NO3)2, are chemical forms of uranium that are
often found in solution with water. They are generally yellow in color and are used in criticality
Uranium reacts readily with air and water. For example, when uranium is machined, small chips
catch fire from the heat of the machining process. Shavings placed in water react to produce
hydrogen gas. The surfaces quickly oxidize to a hard black coating that is at first protective;
however, under adverse conditions, it corrodes and flakes.
Uranium also reacts with hydrogen or tritium gas to form urani um hydride (UH3). Uranium
"beds" a re commonl y used to s tore tr itium.
Uranium hexafluoride (UF6) reacts in moist air to produce hydrogen fluoride (HF) gas, which is
corrosive and can damage the lungs if breathed. Inhalation of HF has resulted in fatalities
following UF6 releases.
The chemical form of uranium is dependent on its intended use and its stage of production. For
example, UF6 is used during the enrichment process, and UO 2 is used as nuclear fuel. When
handling uranium compounds, the possibility of chemical reactions must not be overlooked.