Two example applications of optimization techniques to radiation protection programmes of United States Department of Energy contractors

Six numerical examples of optimization of radiation protection are provided in the appendices of International Commission on Radiological Protection (ICRP) Publication 37. In each case, the calculations are based on fairly well defined parameters and assumptions that were well understood. In the paper, the authors examine two numerical examples that are based on empirical data and less certain assumptions. These examples may represent typical applications of optimization principles to the evaluation of specific elements of a radiation protection programme. In the first example, the optimum bioassay frequency for tritium workers was found to be once every 95 days, which compared well with the recommendations of ICRP Publication 10. However, this result depended heavily on the assumption that the value of a potential undetected rem was US$1000. The second example showed that the optimum frequency for recalibrating Cutie-Pie-type (CP) ionization chamber survey instruments was once every 102 days, which compared well with the Hanford standard frequency of once every 90 days. This result depended largely on the assumption that an improperly operating CP instrument could lead to a serious overexposure. These examples have led us to conclude that optimization of radiation protection programmes must be a very dynamic process. Examples must be recalculated as empirical data grow and improve and as the uncertainties surrounding assumptions are reduced. (author)