The primary aim of the epidemiologic study of one million U.S. radiation workers and veterans [the Million Worker Study (MWS)] is to provide scientifically valid information on the level of radiation risk when exposures are received gradually over time, and not within seconds as was the case for Japanese atomic-bomb survivors. The primary outcome of the epidemiologic study is cancer mortality but other causes of death such as cardiovascular disease and cerebrovascular disease will be evaluated. The success of the study is tied to the validity of the dose reconstruction approaches to provide realistic estimates of organ-specific radiation absorbed doses that are as accurate and precise as possible and to properly evaluate their accompanying uncertainties. The dosimetry aspects for the MWS are challenging in that they address diverse exposure scenarios for diverse occupational groups being studied over a period of up to 70 y. The dosimetric issues differ among the varied exposed populations that are considered: atomic veterans, U.S. Department of Energy workers exposed to both penetrating radiation and intakes of radionuclides, nuclear power plant workers, medical radiation workers, and industrial radiographers. While a major source of radiation exposure to the study population comes from external gamma- or x-ray sources, for some of the study groups there is a meaningful component of radionuclide intakes that require internal radiation dosimetry assessments. Scientific Committee 6–9 has been established by the National Council on Radiation Protection and Measurements (NCRP) to produce a report on the comprehensive organ dose assessment (including uncertainty analysis) for the MWS. The NCRP dosimetry report will cover the specifics of practical dose reconstruction for the ongoing epidemiologic studies with uncertainty analysis discussions and will be a specific application of the guidance provided in NCRP Report Nos. 158, 163, 164, and 171. The main role of the Committee is to provide guidelines to the various groups of dosimetrists involved in the MWS to ensure that certain dosimetry criteria are considered: calculation of annual absorbed doses in the organs of interest, separation of low and high linear-energy transfer components, evaluation of uncertainties, and quality assurance and quality control. It is recognized that the MWS and its approaches to dosimetry are a work in progress and that there will be flexibility and changes in direction as new information is obtained, both with regard to dosimetry and with regard to the epidemiologic features of the study components. This manuscript focuses on the description of the various components of the MWS, on the available dosimetry results, and on the challenges that have been encountered. It is expected that the Committee will complete its report in 2016.

No abstract

No abstract

Foreword Foreword ForewordA core value of the U.S. Department of Energy (DOE) is to ensure the health and safety of DOE employees, contractors, and subcontractors. The Office of Health, Safety and Security (HSS) provides the corporate-level leadership and strategic vision necessary to establish clear expectations for, and provide oversight and enforcement regarding health, safety, environment, and security programs. In support of this mission, the HSS Office of Analysis provides for the collection, analysis, and dissemination of data and performance indicators, such as occupational radiation exposure information.A key safety focus for DOE is to maintain worker radiation exposures below administrative control levels (ACL) and DOE radiation dose limits and to further reduce these exposures to levels that are "as low as reasonably achievable (ALARA)." The annual DOE 2011 Occupational Radiation Exposure Report provides an evaluation of DOE-wide performance regarding compliance with Title 10, Code of Federal Regulations, Part 835, Occupational Radiation Protection dose limits and ALARA process requirements and an overview of the status of radiation exposures of the DOE workforce. In addition, this report serves as a risk management tool for managing radiological safety programs and provides useful information to DOE organizations, epidemiologists, researchers, and national and international agencies involved in developing policies to protect individuals from harmful effects of radiation.The Radiation Exposure Monitoring System (REMS) program remains a key component of HSS oversight and analysis to inform management and stakeholders of the continued vigilance and success of the DOE sites in minimizing radiation exposure to workers. One of the objectives of this report is to provide useful, accurate, and complete information to DOE and the public. As part of a continuing improvement process, we would appreciate your response to the User Survey included at the end of this report. iv DOE 2011 Occupational Radiation Exposure ReportThis page intentionally left blank. (ALARA) process requirements. In addition, the report provides data to DOE organizations responsible for developing policies for protection of individuals from the adverse health effects of radiation. The report provides a summary and an analysis of occupational radiation exposure information from the monitoring of individuals involved in DOE activities. The occupational radiation exposure information is analyzed in terms of aggregate data, dose to individuals, and dose by site over the past five years.It should be noted that was revised as of June 2007, with full implementation required by July 2010. All sites have now transitioned, and therefore this report reflects the changes in dose terminology and dose assessment methodology required by the revision to 10 C.F.R. 835.As an indicator of the overall amount of radiation dose received during the conduct of operations at DOE, the report includes information on collective total effective dose (TED). The ...

No abstract