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X-RAY DOSAGE TO PATIENTS UNDERGOING ORAL ROENTGEN-OGRAPHY

Description: This report endeavors to point out the radiation hazards involved with respect to the patient undergoing oral roentgenography. The dose rate can be as high as 280 r/min. Very definite hematological changes have been observed and are being thoroughly investigated. Recommendations have been suggested to eliminate overexposures.
Date: July 16, 1952
Creator: Nolan, W. E.
Partner: UNT Libraries Government Documents Department

RADIATION HAZARDS FROM THE USE OP DENTAL X-RAY UNITS

Description: It is well known that for many years x-rays have been used in the dental profession as a potent diagnostic tool. Deprived of this means of exploration, the dentist and patient alike would be at a great disadvantage. In spite of the necessity of x-rays in the dental field, little has been done, however, to protect the patient and the dentist from unnecessary exposure. X-rays cannot immediately be felt or seen, and therein lies the hazard attending their use. What cannot be sensed is often ignored, and through unconcern and neglect an exposure resulting in biological impairment or damage may result. It was felt therefore, that the potential hazard occurring during oral roentgenography should be investigated and that the results of the investigation would be of interest to the dental profession. Radiation survey results are shown for six dentists' offices in the San Francisco Bay area.
Date: November 26, 1952
Creator: Nolan, W. E. & Patterson, H. W.
Partner: UNT Libraries Government Documents Department

Neutronics issues and inertial fusion energy: a summary of findings

Description: We have analyzed and compared five major inertial fusion energy (IFE) and two representative magnetic fusion energy (MFE) power plant designs for their environment, safety, and health (ES&H) characteristics. Our work has focussed upon the neutronics of each of the designs and the resulting radiological hazard indices. The calculation of a consistent set of hazard indices allows comparisons to be made between the designs. Such comparisons enable identification of trends in fusion ES&H characteristics and may be used to increase the likelihood of fusion achieving its full potential with respect to ES&H characteristics. The present work summarizes our findings and conclusions. This work emphasizes the need for more research in low-activation materials and for the experimental measurement of radionuclide release fractions under accident conditions.
Date: May 29, 1998
Creator: Latkowski, J. F.
Partner: UNT Libraries Government Documents Department

Robotics crosscutting program: Technology summary

Description: The Office of Environmental Management (EM) is responsible for cleaning up the legacy of radioactive and chemically hazardous waste at contaminated sites and facilities throughout the U.S. Department of Energy (DOE) nuclear weapons complex, preventing further environmental contamination, and instituting responsible environmental management. Initial efforts to achieve this mission resulted in the establishment of environmental restoration and waste management programs. However, as EM began to execute its responsibilities, decision makers became aware that the complexity and magnitude of this mission could not be achieved efficiently, affordably, safely, or reasonably with existing technology. Once the need for advanced cleanup technologies became evident, EM established an aggressive, innovative program of applied research and technology development. The Office of Technology Development (OTD) was established in November 1989 to advance new and improved environmental restoration and waste management technologies that would reduce risks to workers, the public, and the environment; reduce cleanup costs; and devise methods to correct cleanup problems that currently have no solutions. In 1996, OTD added two new responsibilities - management of a Congressionally mandated environmental science program and development of risk policy, requirements, and guidance. OTD was renamed the Office of Science and Technology (OST). This documents presents information concerning robotics tank waste retrieval overview, robotic chemical analysis automation, robotics decontamination and dismantlement, and robotics crosscutting and advanced technology.
Date: August 1, 1996
Partner: UNT Libraries Government Documents Department

Effective use of metrics in an ALARA program

Description: ALARA radiological protection programs require metrics to meet their objectives. Sources of metrics include; external dosimetry; internal dosimetry; radiological occurrences from the occurrence reporting and processing system (ORPS); and radiological incident reports (RIR). The sources themselves contain an abundance of specific ``indicators``. To choose the site-specific indicators that will be tracked and trended requires careful review. This required the end users to expend valuable time and effort to locate the data they needed. To address this problem, a central metrics database has been developed so that customers can have all their questions addressed quickly and correctly. The database was developed in the beginning to answer some of the customer`s most frequently asked questions. It is now also a tool to communicate the status of the radiation protection program to facility managers. Finally it also addresses requirements contained in the Rad Con manual and the 10CFR835 implementation guides. The database uses currently available, ``user friendly``, software and contains information from RIR`s, ORPS, and external dosimetry records specific to ALARA performance indicators. The database is expandable to allow new metrics input. Specific reports have been developed to assist customers in their tracking and trending of ALARA metrics.
Date: July 1, 1996
Creator: Bates, B.B. Jr.
Partner: UNT Libraries Government Documents Department

ALARA Center of Technology -- resource guide

Description: The purpose is to provide a source of information that can be used to assist personnel in the planning, training, and execution of radiological work using the principles of ALARA. This document is not intended to replace HNF or WHC Control Manual requirements. The ALARA Tools-List provides detailed information on the use and procurement of engineered controls, mockup training guidelines, and good radiological work practices that have been proven to be ALARA.
Date: February 5, 1998
Creator: Waggoner, L.O.
Partner: UNT Libraries Government Documents Department

Acceptability of risk from radiation: Application to human space flight

Description: This one of NASA`s sponsored activities of the NCRP. In 1983, NASA asked NCRP to examine radiation risks in space and to make recommendations about career radiation limits for astronauts (with cancer considered as the principal risk). In conjunction with that effort, NCRP was asked to convene this symposium; objective is to examine the technical, strategic, and philosophical issues pertaining to acceptable risk and radiation in space. Nine papers are included together with panel discussions and a summary. Selected papers are indexed separately for inclusion in the Energy Science and Technology Database.
Date: April 30, 1997
Partner: UNT Libraries Government Documents Department

EPR dosimetry teeth in past and future accidents: A prospective look at a retrospective method

Description: Accurate assessments of doses received by individuals exposed to radiation from nuclear accidents and incidents such as those at Hiroshima and Nagasaki, the Nevada test site, Cheliabinsk and Mayak are required for epidemiological studies seeking to establish relationships between radiation dose and health effects. One method of retrospective dosimetry which allows for measurement of cumulative gamma ray doses received by exposed individuals is electron paramagnetic resonance spectroscopy (EPR) of tooth enamel. Tooth enamel stores and retains, indefinitely, information on absorbed radiation dose. And teeth are available in every population as a result of dental extraction for medical reasons including periodontal disease and impacted wisdom teeth. In the case of children, deciduous teeth, which are shed between the ages of 7 and 13, can be a very important dosimetric source if documented collection is implemented shortly following an accident.
Date: March 1, 1997
Creator: Haskell, E.; Kenner, G.; Hayes, R.; Chumak, V. & Shalom, S.
Partner: UNT Libraries Government Documents Department

Analysis of long-term impacts of TRU waste remaining at generator/storage sites for No Action Alternative 2

Description: This report is a supplement to the Waste Isolation Pilot Plant Disposal-Phase Final Supplemental Environmental Impact Statement (SEIS-II). Described herein are the underlying information, data, and assumptions used to estimate the long-term human-health impacts from exposure to radionuclides and hazardous chemicals in transuranic (TRU) waste remaining at major generator/storage sites after loss of institutional control under No Action Alternative 2. Under No Action Alternative 2, TRU wastes would not be emplaced at the Waste Isolation Pilot Plant (WIPP) but would remain at generator/storage sites in surface or near-surface storage. Waste generated at smaller sites would be consolidated at the major generator/storage sites. Current TRU waste management practices would continue, but newly generated waste would be treated to meet the WIPP waste acceptance criteria. For this alternative, institutional control was assumed to be lost 100 years after the end of the waste generation period, with exposure to radionuclides and hazardous chemicals in the TRU waste possible from direct intrusion and release to the surrounding environment. The potential human-health impacts from exposure to radionuclides and hazardous chemicals in TRU waste were analyzed for two different types of scenarios. Both analyses estimated site-specific, human-health impacts at seven major generator/storage sites: the Hanford Site (Hanford), Idaho National Engineering and Environmental Laboratory (INEEL), Lawrence Livermore National Laboratory (LLNL), Los Alamos National Laboratory (LANL), Oak Ridge National Laboratory (ORNL), Rocky Flats Environmental Technology Site (RFETS), and Savannah River Site (SRS). The analysis focused on these seven sites because 99 % of the estimated TRU waste volume and inventory would remain there under the assumptions of No Action Alternative 2.
Date: September 1, 1997
Creator: Buck, J.W.; Bagaasen, L.M.; Bergeron, M.P. & Streile, G.P.
Partner: UNT Libraries Government Documents Department

Solar particle events and their radiation threats

Description: Energetic particles from the Sun have only been studied in detail during the last three decades. The modern record is good, although the number of the largest solar particle events are very few. The nuclides made by solar energetic particles in lunar rocks have been used to extend the record of these particles {approximately} 10{sup 7} years. The modern and ancient records are similar. By combining both sets of data, it has been inferred that solar particle events much larger than the largest events observed during the last four solar cycles are very rare.
Date: March 1998
Creator: Reedy, R. C.
Partner: UNT Libraries Government Documents Department

Morphometry for alpha particle hits of critical targets in the lungs. Final technical report

Description: The objective of this study is to provide detailed data on the number, location and type of critical target cells in the airspaces and to use these data in order to make risk assessments of the health effects of radon and radon progeny in the lungs. This will be done by quantitative morphometric study of the distribution of the various cell types and mucous lining layers in the lungs. The results provide anatomically correct models for dosimetry in the rate and human airways which significantly improve the ability to do risk assessment for radon exposures by providing quantitative data for specific cell types and provide a basis for mechanism based comparison between data available in animal exposures and human epidemiology.
Date: November 1, 1998
Creator: Mercer, R.R.
Partner: UNT Libraries Government Documents Department

Tritium retention and removal on TFTR

Description: Tritium retention and removal are critical issues for the success of ITER or any DT fusion reactor. The Tokamak Fusion Test Reactor, TFTR, is the first fusion facility to afford the opportunity to study the tritium retention and removal over an extended period. In TFTR, tritium accumulates on all surfaces with line of sight to the plasma by codeposition of tritium with carbon. Measurements of both deuterium and tritium retention fractions have yielded retention between 0.2 and 0.6 of the injected fuel in the torus. Tritium has been successfully removed from TFTR by glow discharge cleaning and by air purges. The in-vessel inventory was reduced by a factor of 2, facilitating machine maintenance. In TFTR, the amount of dust recovered from the TFTR vacuum vessel has varied from several grams to a few kilograms.
Date: October 1, 1997
Creator: Mueller, D.; Blanchard, W. & Doyle, B.L.
Partner: UNT Libraries Government Documents Department

Proposed risk evaluation guidelines for use by the DOE-AL Nuclear Explosive Safety Division in evaluating proposed shipments of nuclear components

Description: The licensing requirements of 10 CFR 71 (US Code of Federal Regulations) are the primary criteria used to license proposed US Department of Energy (DOE) shipments of nuclear components. However, if a shipment cannot meet 10 CFR 71 requirements, a Transportation System Risk Assessment (TSRA) is prepared to document: (1) the degree of compliance of proposed DOE shipments of nuclear components with applicable federal regulations, and (2) the risk associated with the proposed shipments. The Nuclear Explosive Safety Division (NESD) of the Department of Energy, Albuquerque Area Office (DOE-AL) is responsible for evaluating TSRAs and for preparing Safety Evaluation Reports (SERs) to authorize the off-site transport. Hazards associated with the transport may include the presence of fissile material, chemically and radiologically toxic uranium, and ionizing radiation. The Nuclear Regulatory Commission (NRC) has historically considered only radiological hazards in licensing the transport of radiological material because the US Department of Transportation considers licensing requirements of nonradiological (i.e., chemically toxic) hazards. The requirements of 10 CFR 71 are based primarily on consideration of radiological hazards. For completeness, this report provides information for assessing the effects of chemical toxicity. Evaluating the degree of compliance with the requirements of 10 CFR 71 is relatively straightforward. However, there are few precedents associated with developing TSRA risk assessments for packages that do not comply with all of the requirements of 10 CFR 71. The objective of the task is to develop Risk Evaluation Guidelines for DOE-AL to use when evaluating a TSRA. If the TSRA shows that the Risk Evaluation Guidelines are not exceeded, then from a risk perspective the TSRA should be approved if there is evidence that the ALARA (as low as reasonably achievable) principle has been applied.
Date: October 1, 1997
Creator: Just, R.A. & Love, A.F.
Partner: UNT Libraries Government Documents Department

A history of the working group to address Los Alamos community health concerns - A case study of community involvement and risk communication

Description: In May 1991, at a Department of Energy (DOE) public hearing at Los Alamos, New Mexico, a local artist claimed there had been a recent brain tumor cluster in a small Los Alamos neighborhood. He suggested the cause was radiation from past operations of Los Alamos National Laboratory. Data from the Laboratory's extensive environmental monitoring program gave no reason to believe this charge to be true but also could not prove it false. These allegations, reported in the local and regional media, alarmed the community and revealed an unsuspected lack of trust in the Laboratory. Having no immediate and definitive response, the Laboratory offered to collaborate with the community to address this concern. The Los Alamos community accepted this offer and a joint Community-Laboratory Working Group met for the first time 29 days later. The working group set as its primary goal the search for possible carcinogens in the local environment. Meanwhile, the DOE announced its intention to fund the New Mexico Department of Health to perform a separate and independent epidemiological study of all Los Alamos cancer rates. In early 1994, after commissioning 17 environmental studies and meeting 34 times, the working group decided that the public health concerns had been resolved to the satisfaction of the community and voted to disband. This paper tells the story of the artist and the working group, and how the media covered their story. It summarizes the environmental studies directed by the working group and briefly reviews the main findings of the epidemiology study. An epilogue records the present-day recollections of some of the key players in this environmental drama.
Date: January 1, 2000
Creator: Otway, Harry & Johnson, Jon
Partner: UNT Libraries Government Documents Department

Spallation Neutron Source Radiation Shielding Issues

Description: This paper summarizes results of Spallation Neutron Source calculations to estimate radiation hazards and shielding requirements for activated Mercury, target components, target cooling water, and {sup 7}Be plateout. Dose rates in the accelerator tunnel from activation of magnets and concrete were investigated. The impact of gaps and other streaming paths on the radiation environment inside the test cell during operation and after shutdown were also assessed.
Date: November 14, 1999
Creator: Azmy, Y.Y.; Barnes, J.M.; Drischler, J.D.; Johnston, J.O.; Lillie, R.A.; McNeilly, G.S. et al.
Partner: UNT Libraries Government Documents Department

Simulation of contaminated sediment transport in White Oak Creek basin

Description: This paper presents a systematic approach to management of the contaminated sediments in the White Oak Creek watershed at Oak Ridge National Laboratory near Oak Ridge, Tennessee. The primary contaminant of concern is radioactive cesium-137 ({sup 137}Cs), which binds to soil and sediment particles. The key components in the approach include an intensive sampling and monitoring system for flood events; modeling of hydrological processes, sediment transport, and contaminant flux movement; and a decision framework with a detailed human health risk analysis. Emphasis is placed on modeling of watershed rainfall-runoff and contaminated sediment transport during flooding periods using the Hydrologic Simulation Program- Fortran (HSPF) model. Because a large number of parameters are required in HSPF modeling, the major effort in the modeling process is the calibration of model parameters to make simulation results and measured values agree as closely as possible. An optimization model incorporating the concepts of an expert system was developed to improve calibration results and efficiency. Over a five-year simulation period, the simulated flows match the observed values well. Simulated total amount of sediment loads at various locations during storms match with the observed values within a factor of 1.5. Simulated annual releases of {sup 137}Cs off-site locations match the data within a factor of 2 for the five-year period. The comprehensive modeling approach can provide a valuable tool for decision makers to quantitatively analyze sediment erosion, deposition, and transport; exposure risk related to radionuclides in contaminated sediment; and various management strategies.
Date: December 31, 1995
Creator: Bao, Y.; Clapp, R.B.; Brenkert, A.L.; Moore, T.D. & Fontaine, T.A.
Partner: UNT Libraries Government Documents Department

Environmental assessment for consolidation of certain materials and machines for nuclear criticality experiments and training

Description: In support of its assigned missions and because of the importance of avoiding nuclear criticality accidents, DOE has adopted a policy to reduce identifiable nuclear criticality safety risks and to protect the public, workers, government property and essential operations from the effects of a criticality accident. In support of this policy, the Los Alamos Critical Experiments Facility (LACEF) at the Los Alamos National Laboratory (LANL) Technical Area (TA) 18, provides a program of general purpose critical experiments. This program, the only remaining one of its kind in the United States, seeks to maintain a sound basis of information for criticality control in those physical situations that DOE will encounter in handling and storing fissionable material in the future, and ensuring the presence of a community of individuals competent in practicing this control.
Date: May 21, 1996
Partner: UNT Libraries Government Documents Department

Technical basis for dose reconstruction

Description: The purpose of this paper is to consider two general topics: technical considerations of why dose-reconstruction studies should or should not be performed and methods of dose reconstruction. The first topic is of general and growing interest as the number of dose-reconstruction studies increases, and one asks the question whether it is necessary to perform a dose reconstruction for virtually every site at which, for example, the Department of Energy (DOE) has operated a nuclear-related facility. And there is the broader question of how one might logically draw the line at performing or not performing dose-reconstruction (radiological and chemical) studies for virtually every industrial complex in the entire country. The second question is also of general interest. There is no single correct way to perform a dose-reconstruction study, and it is important not to follow blindly a single method to the point that cheaper, faster, more accurate, and more transparent methods might not be developed and applied.
Date: January 31, 1996
Creator: Anspaugh, L.R.
Partner: UNT Libraries Government Documents Department

Development of a safety assessment approach for decontamination and decommissioning operations at nuclear facilities

Description: The US Department of Energy (DOE) is responsible for nearly 1000 nuclear facilities which will eventually be decommissioned. In order to ensure that the health and safety of the workers, other personnel on site and the public in general is maintained during decontamination and decommissioning (D&D) operations, a methodology specifically for use in evaluating the nuclear safety of the associated activities is being developed within the Department. This methodology represents not so much a departure from that currently fish in the DOE when conducting safety assessments of operations at nuclear facilities but, rather, a formalization of those methods specifically adapted to the D&D activities. As such, it is intended to provide the safety assessment personnel with a framework on which they can base their technical judgement, to assure a consistent approach to safety assessment of D&D operations and to facilitate the systematic collection of data from facilities in the post-operational part of the life cycle.
Date: December 31, 1994
Creator: Worthington, P.R. & Cowgill, M.G.
Partner: UNT Libraries Government Documents Department

Portable Monitor for Tritium in Air

Description: In the handling of tritium associated with heavy water moderator, there is a possibility that some of it, in the form of tritiated hydrogen or water vapor, may become airborne. An instrument is needed which will quantitatively measure tritium in air in order to protect personnel from the radiation hazard associated with tritium. This paper describes a portable air sampler developed to monitor concentrations of tritium in air between 4 x 10-5 and 1600 x 10-5 microcurie per cubic centimeter.
Date: January 16, 2003
Creator: Anthony, J.D.
Partner: UNT Libraries Government Documents Department

A workshop on developing risk assessment methods for medical use of radioactive material. Volume 2: Supporting documents

Description: A workshop was held at the Idaho National Engineering Laboratory, August 16--18, 1994 on the topic of risk assessment on medical devices that use radioactive isotopes. Its purpose was to review past efforts to develop a risk assessment methodology to evaluate these devices, and to develop a program plan and a scoping document for future methodology development. This report contains presentation material and a transcript of the workshop. Participants included experts in the fields of radiation oncology, medical physics, risk assessment, human-error analysis, and human factors. Staff from the US Nuclear Regulatory Commission (NRC) associated with the regulation of medical uses of radioactive materials and with research into risk-assessment methods participated in the workshop. The workshop participants concurred in NRC`s intended use of risk assessment as an important technology in the development of regulations for the medical use of radioactive material and encouraged the NRC to proceed rapidly with a pilot study. Specific recommendations are included in the executive summary and the body of this report.
Date: August 1995
Creator: Tortorelli, J. P.
Partner: UNT Libraries Government Documents Department

A workshop on developing risk assessment methods for medical use of radioactive material. Volume 1: Summary

Description: A workshop was held at the Idaho National Engineering Laboratory, August 16--18, 1994 on the topic of risk assessment on medical devices that use radioactive isotopes. Its purpose was to review past efforts to develop a risk assessment methodology to evaluate these devices, and to develop a program plan and a scoping document for future methodology development. This report contains a summary of that workshop. Participants included experts in the fields of radiation oncology, medical physics, risk assessment, human-error analysis, and human factors. Staff from the US Nuclear Regulatory Commission (NRC) associated with the regulation of medical uses of radioactive materials and with research into risk-assessment methods participated in the workshop. The workshop participants concurred in NRC`s intended use of risk assessment as an important technology in the development of regulations for the medical use of radioactive material and encouraged the NRC to proceed rapidly with a pilot study. Specific recommendations are included in the executive summary and the body of this report. An appendix contains the 8 papers presented at the conference: NRC proposed policy statement on the use of probabilistic risk assessment methods in nuclear regulatory activities; NRC proposed agency-wide implementation plan for probabilistic risk assessment; Risk evaluation of high dose rate remote afterloading brachytherapy at a large research/teaching institution; The pros and cons of using human reliability analysis techniques to analyze misadministration events; Review of medical misadministration event summaries and comparison of human error modeling; Preliminary examples of the development of error influences and effects diagrams to analyze medical misadministration events; Brachytherapy risk assessment program plan; and Principles of brachytherapy quality assurance.
Date: August 1, 1995
Creator: Tortorelli, J.P.
Partner: UNT Libraries Government Documents Department