Establishing Consensus with Users of Research Irradiator Devices to Facilitate Source Type Replacement

The ability to irradiate cells, tissues, and other biological materials with high-energy photons has been an essential tool in the discovery of numerous biomedical research advancements. Historically, such irradiation was accomplished using sealed sources of radioactive materials in the form of 137Cs or 60Co. After the tragic events of 11 September 2001, a particular focus was placed on the vulnerability that irradiators represented due to the potential malicious acts that might lead to the creation of a radiological exposure or dispersal device. To mitigate this risk exposure, the United States Department of Energy National Nuclear Security Administration (NNSA) developed programs to both enhance the security associated with these devices and to incentivize the replacement of the units with x-ray-based technology. However, a significant barrier to engagement with the exchange program is the hesitancy on the part of the research community that does not wish to disrupt existing and established research protocols. This hesitancy stems from an inherent desire to adhere to the scientific process with the strict control of variables so that a single aspect can be isolated and then determined to result in an effect. A change from a gamma source to an x-ray source introduces a variable that warrants careful consideration and could have significant scientific and data-related impacts. Described here is the process undertaken by the radiation safety program for a major academic biomedical research institution to successfully transition from the use of gamma irradiators to x-ray devices without disrupting or negatively impacting critical research activities. The key to this successful transition was the establishment of consensus amongst the scientific and administrative communities prior to any formal commitment to the NNSA for the replacement endeavor. Ultimately, the researchers have found success in the transition and use of the x-ray irradiator replacements.