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Hanford External Dosimetry Technical Basis Manual PNL-MA-842

Description: The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at the U.S. Department of Energy (DOE) Hanford site. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with requirements of 10 CFR 835, the DOE Laboratory Accreditation Program, the DOE Richland Operations Office, DOE Office of River Protection, DOE Pacific Northwest Office of Science, and Hanford’s DOE contractors. The dosimetry system is operated by the Pacific Northwest National Laboratory (PNNL) Hanford External Dosimetry Program which provides dosimetry services to PNNL and all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since its inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving significant changes to all chapters in the document. Revision numbers that include a decimal fraction reflect minor revisions, usually restricted to ...
Date: April 1, 2010
Creator: Rathbone, Bruce A.
Partner: UNT Libraries Government Documents Department

Hanford External Dosimetry Technical Basis Manual PNL-MA-842

Description: The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program (HEDP) which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee (HPDAC) which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving changes to all chapters in the document. Revision numbers that include a decimal fraction reflect minor revisions, usually restricted to selected chapters or selected pages in the document.
Date: August 28, 2009
Creator: Rathbone, Bruce A.
Partner: UNT Libraries Government Documents Department

Hanford External Dosimetry Technical Basis Manual PNL-MA-842

Description: The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. Rev. 0 marks the first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database.
Date: February 25, 2005
Creator: Rathbone, Bruce A.
Partner: UNT Libraries Government Documents Department

Final Report: Scintillator Materials for Medical Applications, December 1, 1997 - November 30, 1999

Description: From the very beginning of our program we regarded the understanding of the scintillation mechanism as our primary mission. If in addition this understanding could lead to the discovery of a new material, so much the better. When we began this work some nine years ago, the theoretical basis for the scintillation phenomenon was in disarray. The initial and final steps were reasonably well characterized, but there was no consensus on the crucial intermediate, the transfer of energy from the lattice to the emitting center. In the over 40 publications that resulted from this program, we demonstrated that despite the highly insulating nature of the hosts and the great magnitude of the band gap, the primary means of transport is through mobile charge carriers and their sequential capture by the emitting center. Although radical at the time, this picture is now generally accepted throughout the field. Subsequently, we also recognized the critical role that trapping centers localized at lattice defects can play in the process, not merely as passive sources of loss but as active participants in the kinetics. In this sense shallow traps can wreak more havoc than deep ones, impeding the rate by which carriers can reach the emitting centers and seriously slowing the resulting decay. And we established low-temperature thermoluminescence as a comprehensive tool for quantizing these effects. As for new and better materials, our work also had an impact. We were among the first to recognize the potential of LuAlO{sub 3} (lutetium aluminum perovskite, or LuAP) as a detector for PET applications. Although this material has not supplanted LuSiO{sub 5} (lutetium oxysilicate, or LSO) in terms of light output or absence of afterglow, LuAP still exhibits by far the highest figure of merit (light output divided by decay time) of any scintillator material currently known. Our ...
Date: May 1, 2000
Creator: Lempicki, A.; Brecher, C.; Wojtowicz, A.J. & Szupryczynski, P.
Partner: UNT Libraries Government Documents Department

Recent developments in thermoluminescence kinetics: applications to other thermally stimulated processes

Description: Recent thermoluminescence (TL) studies indicate that many kinetic properties are not in accord with the well known 1st and 2nd order TL kinetic equations. For example, the usual equations do not describe: (1) the shape of certain single glow peaks. (2) The shape of glow peaks in many glow curves containing more than one glow peak. (3) The dependence of the peak temperature, the FWHM, the shape, and other properties on the pre-measurement dose. However, the properties of some single glow peaks are precisely described, or closely approximated by, the more general basic equation from which the usual 1st and 2nd order equations are obtained as special cases. Furthermore, glow curves containing more than one glow peak are described by a system of equations that includes interactions between different types of traps and is a straightforward extension of the general one peak equation. This system - called Interactive Kinetics - accounts for most properties, and explains many anomalies, associated with glow curves containing more than one glow peak. It is particularly convenient for computerized analysis procedures. Lastly, it is suggested that other thermally stimulated processes depend on analogous interactions and are describable by similar sets of kinetic equations that are convenient for computer analysis. 11 refs., 2 figs.
Date: August 7, 1985
Creator: Levy, P.W.
Partner: UNT Libraries Government Documents Department

Thermoluminescence systems with two or more glow peaks described by anomalous kinetic parameters

Description: The usual first and second order TL kinetic expressions are based on a number of assumptions, including the usually unstated assumption that charges released from one type of trap, giving rise to one glow peak, are not retrapped on other types of traps, associated with other glow peaks. Equations have been developed describing TL systems in which charges released from one type of trap may be retrapped in other types of traps. Called interactive kinetic equations, they are quite simple but have been studied by numerical methods. In particular, glow curves computed from the interactive kinetic equations have been regarded as data and analyzed by fitting them to the usual first and second order kinetic expressions. All of the anomalous features described above are reproduced. For example, usually the computed glow peaks are well fitted by the first and second order expressions over their upper 60 to 80% but not in the wings. This explains why the usual analysis methods, especially those utilizing peak temperature, full width, etc. appear to describe such peaks. Often unrealistic kinetic parameters are often obtained. Furthermore, the computed glow curves often reproduce the observed dependence on dose.
Date: January 1, 1983
Creator: Levy, P.W.
Partner: UNT Libraries Government Documents Department

Validity of repeated initial rise thermoluminescence kinetic parameter determinations

Description: The validity of thermoluminescence (TL) analysis by repeated initial rise measurements has been studied by computer simulation. Thermoluminescence described by 1st Order, 2nd Order, General One Trap and Interactive TL Kinetics was investigated. In the simulation each of the repeated temperature increase and decrease cycles contains a linear temperature increase followed by a decrease appropriate for radiative cooling, i.e. the latter is approximated by a decreasing exponential. The activation energies computed from the simulated emission are readily compared with those used to compute the TL emission. In all cases studied, the repeated initial rise technique provides reliable results only for single peak glow curves or for glow curves containing peaks that do not overlap and, if sufficiently separated, the lowest temperature peak in multipeak curves. Also the temperatures, or temperature cycles corresponding to correct activation energies occur on the low temperature side of the normal glow curve, often well below the peak temperature. A variety of misleading and/or incorrect results an be obtained when the repeated initial rise technique is applied to TL systems that produce overlapping peaks in the usual glow curve. 6 refs., 10 figs.
Date: January 1, 1990
Creator: Kierstead, J.A. & Levy, P.W.
Partner: UNT Libraries Government Documents Department

Protocols for Thermoluninescence and Optically Stimulated Luminescence Research at DOSAR

Description: The Life Sciences Division (LSD) of Oak Ridge National Laboratory (ORNL) has a long record of radiation dosimetry research at the Dosimetry Applications Research (DOSAR) facility complex. These facilities have been used by a broad segment of the research community to perform a variety of experiments in areas including, but not limited to, radiobiology, radiation dosimeter and instrumentation development and calibration, and materials testing in a variety of radiation environments. Collaborations with the University of Tennessee-Knoxville (UTK) have also led to important contributions in the area of archaeometry, particularly as it relates to the use of radiation dosimetry to date archaeological artifacts. This manual is to serve as the primary instruction and operation manual for dosimetric and archaeometric research at DOSAR involving thermoluminescence (TL) and optically stimulated luminescence (OSL). Its purpose is to (1) provide protocols for common practices associated with the research, (2) outline the relevant organizational structure, (3) identify the Quality Assurance plan, and (4) describe all the procedures, operations, and responsibilities for safe and proper operation of associated equipment. Each person who performs research at DOSAR using TL/OSL equipment is required to read the latest revision of this manual and be familiar with its contents, and to sign and date the manual's master copy indicating that the manual has been read and understood. The TL/OSL Experimenter is also required to sign the manual after each revision to signify that the changes are understood. Each individual is responsible for completely understanding the proper operation of the TL/OSL equipment used and for following the guidance contained within this manual. The instructions, protocols, and operating procedures in this manual do not replace, supersede, or alter the hazard mitigation controls identified in the Research Safety Summary (''Thermoluminescence/Optically Stimulated Luminescence Dosimetry'') for this research, ORNL's Standards-Based Management System or any other official ...
Date: October 11, 2004
Creator: Bernal, SM
Partner: UNT Libraries Government Documents Department

Use of Optically Stimulated Luminescence Imaging Plates and Reader for Arms Control Applications

Description: Optically Stimulated Luminescence (OSL) technology has been pioneered at the Pacific Northwest National Laboratory (PNNL) for applications in personnel radiation dosimetry and commercially has become highly successful in replacing older technologies such as Thermoluminescence Dosimeters (TLDs) and film. OSL phosphors are used to measure radiation exposure by illuminating them with light after ionizing radiation exposure and measuring the amount of light emitted by the OSL phosphor. By using a two-dimensional plate of OSL material and raster scanning a light beam across the OSL plate a radiation pattern or image can be measured. The Arms Control community requires an electrons-free medium to measure the attributes of extent and symmetry on Pu pits in storage containers. OSL technology, used in the two-dimensional imaging mode, provides a means to measure these attributes with exposure times on the order of an hour. A special OSL reader has been built by PNNL to measure OSL imaging plates with a size of 20 cm by 30 cm. The reader uses 10 light emitting diode clusters with 10 corresponding photomultiplier tubes to measure an OSL imaging plate in less than 5 minutes. The resolution of each of the 10 measurement assemblies is 1 square-centimeter. A collimator assembly employing a Venetian-blind type collimator is used in conjunction with the OSL film to image the Pu pit within the storage container. The output of the OSL reader is a two dimensional array of intensities that will be used with the appropriate information barriers to measure extent and symmetry. This device also clearly distinguishes the difference between a point source and a distributed source. Details of the OSL technology, OSL reader system, collimator design, and system performance will be presented.
Date: July 5, 2001
Creator: Miller, Steven D.; Tomeraasen, Paul L.; Burghard, Brion J. & Traub, Richard J.
Partner: UNT Libraries Government Documents Department