Coworker Dosimetry Distributions Used in Dose Reconstructions for the Energy Employees Occupational Illness Compensation Program Act (EEOICPA)
D.W. Hearnsberger1; E.M. Brackett2; S.E. Merwin1; D.L. Cragle3; and J.L. Kenoyer1 (1Dade Moeller and Associates; 2MJW Corporation; 3Oak Ridge Associated Universities)
Coworker exposure profiles for U.S. Department of Energy (DOE) sites and atomic weapons employer (AWE) facilities have been developed by the Oak Ridge Associated Universities (ORAU) Team where available exposure data lend themselves to the creation of viable coworker exposure distributions for both external and internal exposure. The exposure profile for a site is a set of exposure distributions (distributed lognormally) covering each year for which data are available. This presentation describes the approach and processes to be used to develop reasonable exposure profiles based on available dosimetric information for workers at DOE or AWE sites. The exposure profiles have been applied to dose reconstruction for energy employees for whom monitoring data are either inadequate or do not exist and for whom maximizing approaches to dose reconstruction fail to produce a clear decision or produce a probability of causation greater than 50%. These coworker exposure profiles will allow the ORAU Team to apply statistical approaches to assigning exposures to unmonitored and inadequately monitored energy employees, based on external and internal monitoring data that are available for other workers at the same (or a very similar) DOE site or AWE operation. Because the exposure distributions are likely to be lognormal with geometric standard deviations of 3.0 or more, their uncertainties will be included in the dose reconstruction in addition to the uncertainty distributions of the risk coefficients in the Interactive RadioEpidemiological Program (IREP); consequently, this approach will be claimant favorable. Finally, for those energy employees for whom no data are available, but who likely should have been monitored because of a potential for high exposures, the upper bounds of the coworker exposures can be assigned. Work supported by the National Institute for Occupational Safety and Health under Contract No. 200-2002-00593.
