Replacing High-Risk Radioactive Sources and Materials

In considering alternatives to non-isotopic substitutes for high-risk sources, it is important to understand both the uses to which these materials are put and the current technological and economic feasibility of alternative technologies for achieving the same purposes. Making these comparisons can be quite complicated. When judging economic feasibility, for example, overall costs including changes in maintenance, hiring, and training need to be considered, not just the cost of the equipment. Similarly, the more difficult disposal costs and disposal pathways that result from the use of radiological sources must be considered, even if these costs are sometimes currently picked up by national governments. Still, as a rule of thumb, before substituting an alternative non-isotopic device or material for a high-risk radionuclide, the alternative should at least be roughly equivalent in cost and utility for carrying out the intended use as the high-risk radionuclide it would replace. Where equivalence is not possible with an alternative, an evaluation needs to be made as to whether the alternative’s performance is acceptable or if economic or other incentives could shift relative costs and benefits to render the replacement equivalent to the original high-risk source. The paper and presentation describe the most important current uses of hazardous amounts of high-risk materials and considers current challenges to substituting non-isotopic alternatives. A proposal (roadmap) is developed for evaluation and implementation of replacement options.