The Transition from Radioactive Source-Based Irradiators to Alternative Technologies: How the Cesium Irradiator Replacement Program Was Implemented at the University of Alabama at Birmingham

This paper highlights the University of Alabama at Birmingham’s (UAB) experience intransitioning from radioactive source-based irradiators to non-radioisotopic alternativetechnologies. For many years, radioactive source-based irradiators have proven to be avaluable tool to research and medicine at the UAB. However, possession, use, andespecially security of these sources have, and will continue to, become increasinglychallenging due to the university’s requirement to adhere to the United States NuclearRegulatory Commission’s requirements for the physical protection of category 1 andcategory 2 quantities of radioactive material. Despite an initial commitment to greatlyincrease the security of these sources, the university ultimately identified source disposalas the best course of action. The National Nuclear Security Administration Office ofRadiological Security alleviated concerns about executing disposal and shared the capitalcost of the new technology through the Cesium Irradiator Replacement Project (CIRP), alimited and voluntary initiative offering financial incentives to licensees who choose toreplace cesium-137-based irradiators with alternative, non-radioisotopic technologies.The UAB research community did express concerns regarding whether better resultscould be achieved with gamma irradiation versus x-ray irradiation. These concerns were,primarily, addressed through a series of sensitive and very informative discussionsexplaining the facts that surround both methods of research. In this way, the UAB wasable to ensure its researchers’ ability to continue research with minimal interruption. Thediscussions revealed that additional physical protection regulations, emerging securityrisks and threats, and aging irradiators, could add long-term challenges to performingresearch; and the cost of maintaining such controls is expected to increase over time.These concerns along with the opportunity to take advantage of the approximately$500,000 in overall savings provided by the CIRP made technology replacement themost sensible option. This paper will present changes and adjustments necessary for aneffective transition from gamma to x-ray irradiators and UAB’s experience with the CIRP.