Many nuclear weapons complex workers were required to undergo medical x-ray examinations as a condition of their employment. To ensure that their dose reconstructions are complete, it is necessary to include the contributions from these examinations. X-ray procedures that must be evaluated include: (1) posterior-anterior and lateral radiography, and/or photofluorography, of the chest; (2) anterior-posterior, lateral and oblique lumbar, cervical and thoracic radiography of the spine; and (3) radiography of the pelvis. Each is discussed in the context of conditions that existed during the time the worker was employed. For purposes of dose reconstruction, the x-ray beam size is especially important because the dose conversion factors (DCFs) for each specific body organ depend on whether it was in, or on the periphery of, the primary beam. The approach adopted was to use the DCFs, combined with the entrance kerma, to estimate the organ doses. In cases in which beam output data or information on the primary factors influencing the dose are not available, methods to provide conservative (i.e., claimant-favorable) entrance kerma and dose estimates are adopted. These include specific default values for chest radiography. To account for uncertainties, the estimated doses due to x-ray examinations are increased by 30%.
* Dade Moeller & Associates, 1835 Terminal Drive, Suite 200, Richland, WA 99354; † Washington State University at Tri-Cities, 137 Spring, Richland, WA 99354-1651; ‡ Oak Ridge Associated Universities, Dose Reconstruction Project for NIOSH, 4850 Smith Road, Suite 200, Cincinnati, OH 45212.
For correspondence contact: V. Shockley, Dade Moeller & Associates, 1835 Terminal Drive, Suite 200, Richland, WA 99354, or email at SHOCKLEYX2@aol.com.
(Manuscript accepted 9 September 2007)