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Dosimetry experiments at the MEDUSA Facility (Little Mountain).

Description: A series of experiments on the MEDUSA linear accelerator radiation test facility were performed to evaluate the difference in dose measured using different methods. Significant differences in dosimeter-measured radiation dose were observed for the different dosimeter types for the same radiation environments, and the results are compared and discussed in this report.
Date: October 1, 2010
Creator: Harper-Slaboszewicz, Victor Jozef; Shaneyfelt, Marty Ray; Sheridan, Timothy J.; Hartman, E. Frederick & Schwank, James Ralph
Partner: UNT Libraries Government Documents Department

Dependance of TWRS FSAR X/Qs on distance and example doses at Highway 240 with stationary and moving receptors

Description: A discussion of the reasons for the dependance of X/Q on receptor distance and compass sector is presented. In addition, X/Qs are calculated for three receptor scenarios on Highway 240 including a moving receptor. Example radiological doses and toxicological exposures at Highway 240 are calculated for two accidents already analyzed in the TWRS FSAR.
Date: September 23, 1996
Creator: Himes, D.A.
Partner: UNT Libraries Government Documents Department

Taxonomic and developmental aspects of radiosensitivity

Description: Considerable information is available on the effects of radioactivity on adult and early life stages of organisms. The preponderance of data is on mortality after a single irradiation with relatively high doses. Unfortunately, because experiments were carried out under different conditions and for different time periods, the validity of comparing the results from different laxonomic groups is questionable. In general, the conclusions are that there is a relationship (1) between radioresistance to high doses of acute radiation and taxonomy of the organism, primitive forms being more radioresistant than complex vertebrates and (2) between radiosensitivity and developmental stage, early life stages being more sensitive than later stages. The first conclusion may be related to the capability of the organism to repopulate cells and to differentiate and redifferentiate them; the second to the rate of cellular division and to the degree of differentiation. In question, however, is the relevance of the responses from high levels of acute radiation to that of the responses to long-term exposure to low levels of radiation, which are ecologically of more interest. Data from studies of the effects of acute and chronic exposure on development of gametes and zygotes indicate that, for some fishes and invertebrates, responses at the cellular and molecular levels show effect levels comparable to those observed in some mammals. Acute doses between 0,05 and 0.5Cy and dose rates between 0.02 to 0.2mCy/h appear to define critical ranges in which detrimental effects on fertility are first observed in a variety of radiosensitive organisms. To better understand inherent radiosensitivity, we need more information on the ability of cells to repopulate and differentiate and to prevent or repair damage to biological critical molecules, such as DNA, because these factors may alter significantly organisms` responses to radiation.
Date: November 1, 1996
Creator: Harrison, F.L. & Anderson, S.L.
Partner: UNT Libraries Government Documents Department

Dose refinement: ARAC's role

Description: The Atmospheric Release Advisory Capability (ARAC), located at the Lawrence Livermore National Laboratory, since the late 1970�s has been involved in assessing consequences from nuclear and other hazardous material releases into the atmosphere. ARAC�s primary role has been emergency response. However, after the emergency phase, there is still a significant role for dispersion modeling. This work usually involves refining the source term and, hence, the dose to the populations affected as additional information becomes available in the form of source term estimates�release rates, mix of material, and release geometry�and any measurements from passage of the plume and deposition on the ground. Many of the ARAC responses have been documented elsewhere. 1 Some of the more notable radiological releases that ARAC has participated in the post-emergency phase have been the 1979 Three Mile Island nuclear power plant (NPP) accident outside Harrisburg, PA, the 1986 Chernobyl NPP accident in the Ukraine, and the 1996 Japan Tokai nuclear processing plant explosion. ARAC has also done post-emergency phase analyses for the 1978 Russian satellite COSMOS 954 reentry and subsequent partial burn up of its on board nuclear reactor depositing radioactive materials on the ground in Canada, the 1986 uranium hexafluoride spill in Gore, OK, the 1993 Russian Tomsk-7 nuclear waste tank explosion, and lesser releases of mostly tritium. In addition, ARAC has performed a key role in the contingency planning for possible accidental releases during the launch of spacecraft with radioisotope thermoelectric generators (RTGs) on board (i.e. Galileo, Ulysses, Mars-Pathfinder, and Cassini), and routinely exercises with the Federal Radiological Monitoring and Assessment Center (FRMAC) in preparation for offsite consequences of radiological releases from NPPs and nuclear weapon accidents or incidents. Several accident post-emergency phase assessments are discussed in this paper in order to illustrate ARAC�s roll in dose refinement. A brief description of the ...
Date: June 1, 1998
Creator: Baskett, R L; Ellis, J S & Sullivan, T J
Partner: UNT Libraries Government Documents Department

IBM 650 COMPUTER--PROGRAM NUMBER 655 COLLATION OF ROC CODE OUTPUT

Description: Using the output of programs 653 and 654, each card of which contains the dose information for one dose point at one energy, program 655 produces the sum of the dose values of all energies for one dose point. Program details are given including 650 input and output formats, operating instructions, and guides. (auth)
Date: December 19, 1958
Creator: Stueck, C.J.
Partner: UNT Libraries Government Documents Department

PERIODIC RADIATION SURVEY. CORE I, SEED 1. Section 3. Test Results T- 612394

Description: Radiation levels inside the concrete enclosures but outside the reactor plant containers after shutdown were determined. Radiation levels in the 1AC, 1BC boiler chamber enclosures and in the reactor chamber enclosure were on the average higher than in previous tests. The highest reading obtained was 7.5 mr/ hr and the lowest reading was 0.03 mr/hr; the mean level was 3.76 mr/hr as compared to 1.37 mr/hr in previous tests. (W.L.H.)
Date: June 17, 1960
Partner: UNT Libraries Government Documents Department

CHROMOSOMAL ABERRATIONS IN A NATURAL POPULATION OF CHIRONOMUS TENTANS EXPOSED TO CHRONIC LOW-LEVEL ENVIRONMENTAL RADIATION

Description: The salivary gland chromosomes of Chironomus tentans larvae collected from White Oak Creek, an area contaminated by radioactive waste from the Oak Ridge National Laboratory, and from six uncontaminated areas were examined for chromosomal aberrations. White Oak Creek populations were exposed to absorbed doses as high as 230 rads per year or about 1000 times background. Chromosomal maps were constructed to make a general comparison of the banding pattern of the salivary chromosomes of the C. tentans in the East Tennessee area with those of Canada and Europe. These maps were used as a reference in scoring aberrations. Fifteen different chromosomal aberrations were found in 365 larvae taken from the irradiated population as compared with five different aberrations observed in 356 larvae from six control populations, but the mean number of aberrations per larva did not differ in any of the populations. The quantitative amount of heterozygosity was essentially the same in the irradiated and the control population, but there were three times the variety of chromosomal aberrations found in the irradiated area. From this evidence it was concluded that chronic low-level irradiation from radioactive waste was increasing the variability of chromosomal aberrations without significantly increasing the frequency. It was also concluded that chromosomal polymorphism can be maintained in a natural population without superiority of the heterozygous individuals. (C.H.)
Date: January 29, 1964
Creator: Blaylock, B G; Auerbach, S I & Nelson, D J
Partner: UNT Libraries Government Documents Department

Travel for the 2004 American Statistical Association Biannual Radiation Meeting: "Radiation in Realistic Environments: Interactions Between Radiation and Other Factors

Description: The 16th ASA Conference on Radiation and Health, held June 27-30, 2004 in Beaver Creek, CO, offered a unique forum for discussing research related to the effects of radiation exposures on human health in a multidisciplinary setting. The Conference furnishes investigators in health related disciplines the opportunity to learn about new quantitative approaches to their problems and furnishes statisticians the opportunity to learn about new applications for their discipline. The Conference was attended by about 60 scientists including statisticians, epidemiologists, biologists and physicists interested in radiation research. For the first time, ten recipients of Young Investigator Awards participated in the conference. The Conference began with a debate on the question: “Do radiation doses below 1 cGy increase cancer risks?” The keynote speaker was Dr. Martin Lavin, who gave a banquet presentation on the timely topic “How important is ATM?” The focus of the 2004 Conference on Radiation and Health was Radiation in Realistic Environments: Interactions Between Radiation and Other Risk Modifiers. The sessions of the conference included: Radiation, Smoking, and Lung Cancer Interactions of Radiation with Genetic Factors: ATM Radiation, Genetics, and Epigenetics Radiotherapeutic Interactions The Conference on Radiation and Health is held bi-annually, and participants are looking forward to the 17th conference to be held in 2006.
Date: July 21, 2009
Creator: Brenner, David J.
Partner: UNT Libraries Government Documents Department

GASPAR II: Technical reference and user guide

Description: This report describes the computer program GASPAR II used by the staff of the US Nuclear Regulatory Commission to perform environmental dose analyses for releases of radioactive effluents from nuclear power plants into the atmosphere. The analyses estimate radiation dose to individuals and population groups from inhalation, ingestion (terrestrial foods), and external-exposure (ground and plume) pathways. The calculated doses provide information for National Environmental Policy Act (NEPA) evaluations and for determining compliance with Appendix I of 10 CFR 50 (the ''ALARA'' philosophy). The report also instructs the user in preparing input to the program, describes the mathematical models that are used, and supplies detailed information on program structure and parameters used to modify the program. 20 refs., 11 figs., 77 tabs.
Date: March 1, 1987
Creator: Strenge, D.L.; Bander, T.J. & Soldat, J.K.
Partner: UNT Libraries Government Documents Department

Calorimetry

Description: The techniques and equipment currently employed for calorimetric dosimetry have been briefly surveyed and the status of some recent measurements presented. The problems which remain to be investigated are: the thermal defect, the suitability of A-150 plastic as a material for heavy charged particle calorimetry and calorimeter designs that are appropriate for specific radiation situations, including cryogenic calorimeters.
Date: January 1, 1978
Creator: McDonald, J. C.
Partner: UNT Libraries Government Documents Department

Occupational dose reduction at Department of Energy contractor facilities: Bibliography of selected readings in radiation protection and ALARA

Description: This bibliography contains abstracts relating to various aspects of ALARA program implementation and dose reduction activities, with a focus on DOE facilities. Abstracts included in this bibliography were selected from proceedings of technical meetings, journals, research reports, searches of the DOE Energy, Science and Technology Database (in general, the citation and abstract information is presented as obtained from this database), and reprints of published articles provided by the authors. Facility types and activities covered in the scope of this report include: radioactive waste, uranium enrichment, fuel fabrication, spent fuel storage and reprocessing, facility decommissioning, hot laboratories, tritium production, research, test and production reactors, weapons fabrication and testing, fusion, uranium and plutonium processing, radiography, and aocelerators. Information on improved shielding design, decontamination, containments, robotics, source prevention and control, job planning, improved operational and design techniques, as well as on other topics, has been included. In addition, DOE/EH reports not included in previous volumes of the bibliography are in this volume (abstracts 611 to 684). This volume (Volume 5 of the series) contains 217 abstracts. An author index and a subject index are provided to facilitate use. Both indices contain the abstract numbers from previous volumes, as well as the current volume. Information that the reader feels might be included in the next volume of this bibliography should be submitted to the BNL ALARA Center.
Date: December 1, 1993
Creator: Dionne, B.J.; Sullivan, S.G. & Baum, J.W.
Partner: UNT Libraries Government Documents Department

Field characterization and personal dosimetry at a high energy ion accelerator

Description: The response of a variety of dosimeters was evaluated in the radiation field outside the shielding of the Lawrence Berkeley Laboratory Bevalac Biomedical Facility. The primary beam was 580 MeV/center dot/A neon ions, incident upon a 30.5-cm polyethylene cube. The field was characterized by a neutron spectrometer consisting of Bonner spheres and other detectors and by estimates of charged particle fluences in NTA film and in the Berklet spectrometer. The responses of American Acrylics CR-39 track-etch plastic detectors and AECL (Canada) type BD-100 Bubble Detectors were compared to those of NTA film, Andersson-Braun remmeter and recombination-chamber results as well as to reference dose equivalents based upon the unfolded neutron spectrum. Evaluations of these dosimeters are discussed. 7 refs., 4 figs.
Date: March 1, 1988
Creator: Greenhouse, N.A.; Busick, D.D.; de Castro, T.M.; Elwyn, A.J.; Hankins, D.E.; Ipe, N.E et al.
Partner: UNT Libraries Government Documents Department

Energy imparted, energy transferred, and net energy transferred

Description: The ICRU-defined non-stochastic quantity absorbed dose is related to the stochastic quantity energy imparted. In the present paper the corresponding stochastic quantities energy transferred and net energy transferred are defined as precursors for kerma and collision kerma, respectively. This forms a rational fundamental framework for radiation dosimetry which facilitates its teaching and understanding. For neutrons collision kerma coincides with kerma, because the heavy secondaries do not lose significant energy by radiative processes (e.g., bremsstrahlung).
Date: January 1, 1983
Creator: Attix, F.H.
Partner: UNT Libraries Government Documents Department

Impact of risk considerations on dosimetry of radiopharmaceuticals

Description: Estimates of the absorbed dose from clinical procedures involving the administration of radiopharmaceuticals are used primarily to determine the presumed risk of various procedures so that, in-so-far as possible, the selection of a given procedure can be based on a comparison of risk. Although this has been the basic objective, risk evaluation has generally been separated from the dosimetry considerations. In the recent revision of its radiation protection guidance, the International Commission on Radiological Protection (ICRP) has embodied risk considerations in its recommendations and risk concepts have become an integral part of the dosimetric framework. The impact of these considerations on the dosimetric assessments of radiopharmaceuticals and the resulting need for additional information is discussed.
Date: January 1, 1981
Creator: Eckerman, K.F.
Partner: UNT Libraries Government Documents Department

Guide to radiological accident considerations for siting and design of DOE nonreactor nuclear facilities

Description: This guide was prepared to provide the experienced safety analyst with accident analysis guidance in greater detail than is possible in Department of Energy (DOE) Orders. The guide addresses analysis of postulated serious accidents considered in the siting and selection of major design features of DOE nuclear facilities. Its scope has been limited to radiological accidents at nonreactor nuclear facilities. The analysis steps addressed in the guide lead to evaluation of radiological dose to exposed persons for comparison with siting guideline doses. Other possible consequences considered are environmental contamination, population dose, and public health effects. Choices of models and parameters leading to estimation of source terms, release fractions, reduction and removal factors, dispersion and dose factors are discussed. Although requirements for risk analysis have not been established, risk estimates are finding increased use in siting of major nuclear facilities, and are discussed in the guide. 3 figs., 9 tabs.
Date: January 1, 1986
Creator: Elder, J.C.; Graf, J.M.; Dewart, J.M.; Buhl, T.E.; Wenzel, W.J.; Walker, L.J. et al.
Partner: UNT Libraries Government Documents Department