. "V. Committee's Findings Related to NTPR Dose Reconstruction Program." A Review of the Dose Reconstruction Program of the Defense Threat Reduction Agency. Washington, DC: The National Academies Press, 2003.
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there was one case of macular degeneration (case #71). In case #64, both skin and eye doses were recorded explicitly, but the file did not indicate the diseases involved. Of the 27 cases, skin or eye dose was recorded explicitly in nine files for which the claim or other indication of skin or eye disease occurred in 1998 or later (cases #9, 12, 25, 39, 40, 64, 66, 96, and 97). The other 18 files—for claims or other indications of skin or eye disease that occurred before 1998—did not provide explicit skin or eye doses. That distribution is consistent with information provided by the NTPR program (Schaeffer, 2002c): skin dose assessments were not performed routinely before 1998. Table V.B.2 summarizes the nine files that state explicit skin or eye doses, and some representative assessments are discussed below.
V.B.6.2Summaries of Selected Skin and Eye Dose Assessments
In case #9, the beta dose calculations appear to have been performed with mathematical software, and the data and calculations were annotated. The beta-to-gamma dose ratio method described in Barss (2000) and Section IV.B.4 was used for the beta dose to the skin and lens of the eye from exposure to contaminated surfaces outside the body. Before the beta-to-gamma dose ratios were applied, the upper bound of each component of the gamma dose was determined by multiplying the estimated gamma dose by an upper-bound factor (ratio of upper bound to central estimate). Upper-bound factors of 1.2–1.6 appear to have been used for gamma doses obtained from film badges and reconstructions. A substantial portion of the beta dose to the upper arms and forearms was ascribed to two 1-min exposures to highly contaminated towlines. The assumed distances were 20 cm for the forearm and 40 cm for the upper arm. No uncertainties were ascribed to the exposure time or the distances. The calculated doses would be very sensitive to errors in the determinations of such small times and distances. Although Barss (2000) includes methods for determining beta dose from standing in descending fallout and from skin contamination, there did not appear to be any consideration of those pathways in this case. That could have been appropriate, but it would have been useful to discuss the reasons for not including them.
In case #64, the file contains no narrative describing the dose assessment or detailed calculations. The gamma dose was determined to be 0.7 rem from ship dose tables, and the neutron dose was determined to be zero on the basis of references. As indicated in Table V.B.2, the upper-bound gamma dose was set to 1.6 rem, but without explanation. There were no beta dose calculations, but the skin and eye doses were also set to 1.6 rem, implying a beta-to-gamma dose ratio of 1. There was no consideration of skin contamination or immersion dose. The veteran performed basic seamanship and watch duties on the USS Allen M. Sumner and the USS Moalem. If he worked outside on contaminated ships, some beta dose would be expected from contaminated surfaces and possibly from skin contamination or descending fallout.