Test Results Using a Bell Jar to Measure Containment Vessel Pressurization

A bell jar is used to determine containment vessel pressurization due to outgassing of plutonium materials. Fifteen food cans containing plutonium bearing materials, including plutonium packaged in direct contact with plastic and plutonium contaminated enriched uranium oxide have been tested to date. As expected, minimal pressurization occurs and in some cases a slight depressurization has been observed. Linear extrapolation of the greatest pressurization observed in the bell jar to a typical drum shipping container (such as a 9975) has been performed. Pressurization from this particular can packaged for one year in a 9975 container is negligible.