WAM-D - Special Session: Military Health Physics North 226ABC 08:00 - 11:55
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| Business Meeting 11:10-12:00 PST |
BREAK
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WAM-D.
United States Air Force Dosimetry Program Conversion from TLD to OSL: Programmatic Aspects JR Cezeaux*, U.S. Air Force
; SG Duncan, U.S. Air Force; DL Pugh, U.S. Air Force; JJ Wang, U.S. Air Force
Abstract: In 2018, the United States Air Force Radiation Dosimetry Laboratory began a whole body dosimetry transition from thermoluminescent dosimeters (TLDs) to optically stimulated luminescence (OSL) dosimeters. They fielded the new badges to users in January 2020, reporting their first OSL-detected doses in February 2020. This presentation will address the required policy changes, business practices, quality system impacts, and advances in online program management and reporting that were part of the wholesale conversion from legacy systems.
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WAM-D.1
08:00 Assessing and Remediating Fallout of Operational Equipment GR Fairchild*, U.S. Navy
; WA Durosseau, U.S. Navy; DE Farrand, U.S. Navy
Abstract: Following exposure to radiological fallout, gross decontamination efforts such as scrubbing with detergents and rinsing with water can be used to remove loose contamination from external surfaces of operational equipment and platforms. Internal to the equipment though are many components that involve or rely on air movement, which may result in concentration of fallout contamination that can adhere to internal surfaces. Maintenance, repair, or replacement of the affected systems or components can liberate the material, potentially posing a risk to personnel or the environment. Assessment and remediation of all equipment may take several years to complete depending on operational deployments and availability of uncontaminated parts. Military health physicists must integrate with system engineers, maintenance personnel, and program managers to apply protective health physics practices and regulatory requirements. Depending on the scope of impact, a formal program for tracking affected components may be required. The process of returning equipment to the fleet and establishing an effective service-wide fallout remediation program will be discussed.
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WAM-D.2
08:25 A Mechanistic Mathematical Model for Wound Healing After Radiation Combined Injury and the Effects of Pathological Inflammation RL Jennings*, Applied Research Associates, Inc.
; AR Creel, Applied Research Associates, Inc.; CA Romanowski, Applied Research Associates, Inc.; KK Sewsankar, Applied Research Associates, Inc.
Abstract: Following a nuclear detonation event, which is characterized by three primary insult environments (blast, radiation, and thermal fluence), historical evidence demonstrates majority of casualties will exhibit radiation combined injury (RCI)- radiation exposure in conjunction with another trauma. Understanding the collective effects of RCI is fundamental for gauging injury severity and predicting outcomes. Common features, such as tissue damage, allow for a reductionist approach to studying RCI and eventually modeling its effect on the human immune system. To repair tissue damage, an overlapping, coordinated sequence of phases (hemostasis, inflammation, proliferation, and remodeling) occurs. Pathological inflammation during this process impairs wound healing, increasing the likelihood of adverse individual outcomes for RCI which are already complicated by varying magnitudes of radiation exposure and injury severity. Here, we introduce an immunophysiological model of local dermal wound healing following radiation and thermal burn injury. The model consists of a system of nonlinear ordinary differential equations that describe dynamics between various immune cells, such as neutrophils, macrophages, and lymphocytes, and fibroblasts. We utilize the model to first explore the effect of different inflammatory profiles in promoting timely tissue healing and preventing secondary infection for thermal burn injury. Radiation exposure is then incorporated, allowing us to numerically investigate different pathophysiological processes that reproduce the observed synergistic effects of RCI on delayed healing.
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WAM-D.3
08:50 Impact Analysis of Different ENDF Libraries and Estimating the Fallout Environment JT Dant*, Applied Research Associates
; JJ Molgaard, DTRA
Abstract: Surface detonation of a nuclear bomb will cause catastrophic damage and generate large amounts of fallout that can be transported tens to hundreds of kilometers. The Defense Threat Reduction Agency (DTRA) maintains the Hazard Prediction and Assessment Capability (HPAC), a software application used to model the hazardous environments generated by a nuclear detonation. The primary radioactive component of this environment, the fission products generated from the nuclear detonation, depends on the fission neutron energy and fuel. A recent review of the fission product inventories used as source terms in HPAC has highlighted the need to examine this data and quantify the impact of improved decay libraries on initial source terms and ultimately casualty estimates. The Evaluated Nuclear Data File (ENDF) is the decay library typically used to generate the fission product inventories that populate the HPAC activity vectors, which were generated in 2009 using the Standardized Computer Analyses for Licensing Evaluation version 5.1 (SCALE 5.1) that also implements ENDF/B-VI.8 (released in 2001). SCALE 6.1 and newer versions utilize ENDF/B-VII.1 (released in 2011). Pairing SCALE with the limited distribution Fallout Analysis Tool (FAT) facilitates the automated generation of problem specific activity vectors formatted for HPAC. FAT was recently employed to investigate the impact of changes from B-VI to B-VII. The analysis shows updated activity vectors produce measurable and potentially significant differences that may impact anticipated dose rates and casualty estimates generated by the Health Effects from Nuclear and Radiological Environments (HENRE) module within HPAC. For example, the 99Mo activity is observed to change by more than 80%. Accurate estimation of the source term is essential for minimizing dose and implementing appropriate life-saving actions to mitigate both acute effects of radiation and long-term risks.
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WAM-D.4
09:15 United States Air Force Dosimetry Program Conversion from TLD to OSL: Technical Aspects DL Pugh*, U.S. Air Force
; JJ Wang, U.S. Air Force; JR Cezeaux, U.S. Air Force; SG Duncan, U.S. Air Force
Abstract: In 2018, the United States Air Force Radiation Dosimetry Laboratory began a whole body dosimetry transition from thermoluminescent dosimeters (TLDs) to optically stimulated luminescence (OSL) dosimeters. They fielded the new badges to users in January 2020, reporting their first OSL-detected doses in February 2020. This presentation will address the resultant changes in process intensity, time required, minimum detectable dose, average customer doses, and other technical aspects of the implementation.
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09:40 BREAK
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WAM-D.5
10:10 Defense Health Agency Integrated Radiation Safety Program RA Reyes*, U.S. Army
; MW Bower, Defense Health Agency; NG Keeney, Defense Health Agency; S Shivji, Defense Health Agency; RN Wagner, Defense Health Agency; KO Ely, Defense Health Agency
Abstract: The Defense Health Agency (DHA) assumed responsibility of medical Radiation Health functions at military treatment facilities (MTFs) based on the National Defense Authorization Act (NDAA) for Fiscal Year (FY) 2017, Section 702. The DHA must integrate military Services radiation safety programs to provide effective oversight and accountability for radiation protection. The integration plan includes standardizing metrics and reporting, revising policies, and implementing standardized procedures to prevent harm and meet statutory requirements.
Historically, military Services conducted medical radiation health independently. The Services have different reporting and oversight structures and policies, which introduce complexities that challenge DHA’s current oversight of individual radiation protection programs. The DHA has a Radiation Safety Program that manages the safe use of radioactive materials under its medical NRC License, covering 30 medical activities. These activities include 29 MTFs (15 Army, 9 Navy, 5 Air Force) and the Medical Education and Training Campus (METC). Each individual program under the DHA Radiation Safety umbrella has an authorization and a local Radiation Safety Committee.
The safe use of ionizing- and non-ionizing radiation equipment at all medical activities under the DHA (all MTFs, the METC, Dental, Veterinary, and outlying clinics) remains under the oversight of the Services. This discussion delineates the necessary steps and conditions to move towards a DHA integrated Radiation Safety program, inclusive of both radioactive material and radiation-producing devices. It highlights the challenges posed by the transition and outlines three lines of effort: (1) the improvement of programmatic oversight for NRC-regulated activities; (2) the standardization of ionizing/non-ionizing radiation metrics and reporting requirements; and (3) the revision of the Department of Defense and DHA Radiation Safety policies, procedures, and regulations.
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WAM-D.6
10:30 Radar for Tracking Postdetonation Debris—Preliminary Findings DA Hooper*, Oak Ridge National Laboratory
; ED Kabela, Oak Ridge National Laboratory; CD Cooke, Oak Ridge National Laboratory; MR Brown, Oak Ridge National Laboratory
Abstract: Following an explosion from an unknown or suspected device (e.g., an artillery shell, a radiological dispersion device, or a nuclear weapon), local downwind responses may vary based on the suspected nature of the debris. Is it radioactive? Are chemical agents suspected? Where is the debris heading? For consequence management, debris characterization from radar data may help inform the best use of assets during the early response phase. On a battlefield, rapid answers to these questions could aid warfighters in critical decision making, such as whether to shelter, move, or ignore the debris. These decisions must be made nearly instantly and may have significant impacts on warfighter health and mission success. In this research, we employed a mobile X-band weather radar to scan debris plumes from various artillery shells at Dugway Proving Ground. The objective was to determine if there were signatures in the radar data to consider development of discriminatory algorithms and if the radar data could be used to sufficiently model the wind field to predict the future location of the debris. Despite some technical difficulties that limited data collection, sufficient evidence was generated to suggest that discrimination and prediction were indeed possible and that rapid algorithms may be able to provide nearly instant information for early response to potential explosive debris threats.
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WAM-D.7
10:50 Estimating Operational Internal Dose from Predicted Localized Fallout JJ Frey*, Air Force Institute of Technology
Abstract: The internal dose rate hazard from early fallout generated by a near-surface nuclear detonation has been estimated using ICRP 119 inhalation dose coefficients and the DELFIC fallout modeling code as incorporated into two ORNL-maintained nuclear forensic mission planning tools. The Apple II test shot, conducted in 1955 at the Nevada Test Site during Operation Teapot, was used as the basis for the simulation nuclear event and historical weather parameters. Incorporating internal dose contributions from a full intersection of isotopes present in both ICRP 119 and DELFIC’s modeled isotopic inventory, the potential ratio of simulated internal to external dose rate contributions was on the order of 10-3 or less within the time and spatial domain of forensic interest, in agreement with the conclusions of previous researchers of this topic. The results indicate that the internal dose hazard can be reasonably ignored as an operational planning factor during post-detonation nuclear forensic ground collection missions, even when employing conservative assumptions regarding resuspension and inhalation efficiency across the modeled particle size distribution.
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