Radiation exposure assessment for Portsmouth Naval Shipyard health studies.
Daniels-RD; Taulbee-TD; Chen-P
Radiat Prot Dosim 2004 Jul; 111(2):139-150
Occupational radiation exposures of 13,475 civilian nuclear shipyard workers were investigated as part of a retrospective mortality study. Estimates of annual, cumulative and collective doses were tabulated for future dose-response analysis. Record sets were assembled and amended through range checks, examination of distributions and inspection. Methods were developed to adjust for administrative overestimates and dose from previous employment. Uncertainties from doses below the recording threshold were estimated. Low-dose protracted radiation exposures from submarine overhaul and repair predominated. Cumulative doses are best approximated by a hybrid log-normal distribution with arithmetic mean and median values of 20.59 and 3.24 mSv, respectively. The distribution is highly skewed with more than half the workers having cumulative doses <10 mSv and >95% having doses <100 mSv. The maximum cumulative dose is estimated at 649.39 mSv from 15 person-years of exposure. The collective dose was 277.42 person-Sv with 96.8% attributed to employment at Portsmouth Naval Shipyard.
Radiation-exposure; Exposure-assessment; Shipyard-industry; Shipyard-workers; Shipyards; Shipbuilding-industry; Nuclear-radiation
Division of Surveillance, Hazard Evaluations, and Field Studies, National Institute for Occupational Safety and Health, 5555 Ridge Avenue, R-44, Cincinnati, OH 45213
Radiation Protection Dosimetry