Proposed extension of Raschig ring standard to low enriched uranium fuels

Subcommittee 8 of the Standards Committee of the American Nuclear Society has conducted the prescribed five-year review and update of ANSI N16.4-1971, which provides guidance for the use of borosilicate glass Raschig rings as a neturon absorber in solutions of highly enriched fissile materials. The proposed revision to the Standard extends its application to low enriched 235U fuels based on the 235U concentration in the vessel and to a limited range of alkaline environments. It incorporates standard American Society for Testing and Materials chemical acceptance tests for the glass, a chemical acceptance test for its acceptability in an alkaline environment, and a test that provides information on volume loss due to chemical reaction in addition to that due to settling