Comparison of dose histories for U.S. nuclear power plant workers, based on records held by a major dosimetry service company and on the NRC REIRS database.
In order to conduct valid epidemiological studies of nuclear power plant workers, good information on the workers' radiation dose histories is essential. Dose records held by a major dosimetry service company and on the Nuclear Regulatory Commission's Radiation Exposure Information and Recording System have been compared for a sample of 99 workers. About half of the workers in the sample had no records on the Radiation Exposure Information and Recording System, since they had not terminated employment at a Nuclear Regulatory Commission-licensed facility; accordingly, their career doses (as recorded by the service company) were generally higher than those for workers on the Radiation Exposure Information and Recording System. For nearly half of the workers with records on both databases, the total dose recorded for terminated employments at nuclear power plants differed by at least a factor of 5 between the databases. In absolute terms, these differences were of the order of 100 mSv or more. An approach that utilized both the Radiation Exposure Information and Recording System and the dosimetry service company's records might be of value in constructing dose histories for a large epidemiological study. However, the comparisons presented here support the initiatives of the Nuclear Regulatory Commission to request licensees to report voluntarily career doses for current employees. These data are essential if a large and valid epidemiological study of nuclear plant workers is to be conducted in the foreseeable future.