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Discover an exceptional range of special sessions explicitly tailored for CHPs. We feature diverse sessions covering the latest topics and trends in the field, presented by leading experts and professionals across varying industries.
2023 Special Session
The HPS Annual Meeting was hosted July 2023, in Nation Harbor MD including the presentation of the AAHP Special Sessions. CHPs are encouraged to review these sessions, both for your personal enrichment and to support the AAHP.Learn More About HPS
The topic of this year’s session was Radiological Dispersion: Risk and Consequences. This will consist of some hard science topics including experimental work, modeling, and analysis after a general introduction to the subject area. Presenters represent national laboratories and include research conducted at universities.
Presenters and topics include:
- Gus Potter, Sandia National Laboratories, Introduction to Radiation Dispersal and Consequences
- Shraddha Rane, Sandia National Laboratories, RDD Risk—A Holistic Model for Radiological Facilities (work performed at Purdue University)
- Heather Pennington, Sandia National Laboratories, Radiological Dispersal Parameters
- Charles Weber, Oak Ridge National Laboratory, Chemical Analysis of Cesium Chloride Sealed Sources
- Stephen Musolino, Brookhaven National Laboratory, Evaluation of the Radioactive Material Release in the Harborview Research and Training Building and Implications for Emergency Response
- Andrew Glen, Sandia National Laboratories, A Study of Suspension and Resuspension of Americium Surrogate Aerosol
- Mathew Snow, Idaho National Laboratory, Evaluating Hazards Associated with Dispersed AmBe and Cs Source Materials
- Larry Trost and Vanessa Vargas, Sandia National Laboratories, The Economic Impact of Radiological Dispersal Device Effects
View Past Sessions
Choose a card below to view a list of presentations for each year:
Potential Health Effects of Low Dose Radiation and The Role of Radiation Protection Professionals
Boice JD (NCRP, Vanderbilt)
Radiation epidemiology is the study of human disease following radiation exposure to populations. Radiation epidemiology has been around for well over 100 years, starting with the radium dial painters in the 1920s and most recently with the studies of large-scale radiation worker populations. Radiation epidemiology is so sophisticated that it is used for the setting of radiation protection standards as well as to compensate nuclear weapons workers, nuclear weapons test participants, and other occupationally exposed workers.
It is known with high assurance that radiation effects at levels above 100-150 mGy can be detected as evidenced in multiple populations conducted around the world. The challenge for radiation epidemiology is evaluating the effects at very low doses, below about 100 mGy, and then assessing the risks following low-dose-rate exposures over several years. The challenge for epidemiology is that the small signal, excess numbers of cancers associated with low-dose radiation exposure is so tiny that it cannot be seen against the very high natural occurrence of cancer in our society; i.e., reaching approximately 40% of the population. Thus, extrapolation models have been used for the management of risk at low doses, none of which are entirely satisfactory.
An overview of recently conducted radiation epidemiologic studies that provide estimates of risk following radiation exposures will be presented. Then suggested approaches will be touched upon on how to improve the estimates of radiation risk considering, for example, biologically-based models that will be the focus of subsequent presentations in this symposium.
Favret DJ, Metting NF, Dillard JR, Al-Nabulsi I, Wallo A (US Department of Energy)
The Department of Energy (DOE) is responsible for establishing radiation protection standards, limits, and program requirements for the protection of workers, the public, and the environment, from the conduct of DOE activities (pursuant to the Atomic Energy Act of 1954, as amended). Integrating both national and international consensus where applicable, DOE has developed and implemented radiation protection standards that use the Linear-No-Threshold (LNT) Model. Radiation scientists within DOE support the continued need for experimental research, such as the Low Dose Radiation Research Program, to provide a better understanding of radiation effects on biological systems and the possible impact of exposures on subsequent health risk. This paper will explore DOEâ€™s experience in promulgating radiation protection standards and will also explore DOEâ€™s experience in conducting research to inform the development of future national radiation risk policy for the workplace and the public.
Boyd MA (U.S. EPA)
The U.S. Environmental Protection Agency (EPA) establishes dose – and risk-based standards for control of radioactivity in the environment. Through its federal guidance authority, EPA also advises the President on health related radiation matters, including guidance to all federal agencies for setting radiation standards. In carrying out this authority, the Atomic Energy Act of 1954, as amended, instructs EPA to consult scientists and experts including the National Academy of Sciences (NAS), the National Committee [sic] on Radiation Protection and Measurements (NCRP), and qualified experts in biology, medicine and health physics (AEA Section 274(h)). The NAS Biological Effects of Ionizing Radiation (BEIR) reports and reports of the NCRP have relied on major radiation epidemiology studies to estimate dose response relationships, particularly for estimating the risk of radiation-induced cancer. Current federal radiation regulations and guidance are largely based on these reports and related peer reviewed scientific studies. Federal statutes and legal interpretations of those statutes often demand that radiation regulations be set at risk levels below where effects are observed and unquestionable. There is considerable evidence that at cumulative doses of 100 mSv or more above natural background, the dose response curve is more or less linear in the range of interest for environmental exposures. While epidemiology can confirm that there are age – and sex-related differences in radiosensitivity at these dose levels, it cannot tell us the degree of variability in radiosensitivity among otherwise similar members of a population. Relaxing or strengthening current radiation regulations must then await a better understanding of the biological mechanisms and signatures of radiogenic cancer. For these reasons, EPA is interested in following closely the national and international low dose research efforts that are ongoing or planned.
Jones CG (US Nuclear Regulatory Commission)
For nearly 50 y, the U.S. Nuclear Regulatory Commission has been a leader in the development of radiation protection regulations and guidance for protecting workers, the public and the environment. In 1971, NRCâ€™s predecessor, the Atomic Energy Commission, incorporated the concept of â€œas low as reasonably achievableâ€ or ALARA into its radiation protection policies in response to the expanding use of nuclear power. While the NRC acknowledges that the basis for ALARA (i.e., that the stochastic effects of radiation do not have a lower dose threshold) is not accepted by all persons, it continues to serves as the basis of its regulatory approach and is consistent with the views of national and international expert recommendations.
Over the years, NRC and other Federal agencies have been petitioned to revise the basis for their radiation protection policy. This presentation will explore opportunities for moving forward to strike the right balance between the potential risks and benefits of radiation in establishing radiation protection policy.
Mitchell B (INPO)
INPO and nuclear power industry approach to maintaining worker dose low starts with radiological protection standards of excellence.
This provides a foundation for industry guidelines, an ability to evaluate and monitor performance, and establishment of the use of operating experience. These foundations established collective radiation exposure goals that shaped and influenced and methods to reduce source term, minimize the risk to workers, and result in a steady reduction in worker dose.
Irwin WE (Vermont Department of Health)
Every day in every state, human exposures to chemicals and radioactive materials are being managed by government agencies for a variety of scenarios. The typical risk management perspective practiced in some states is to manage risk from exposures to those agents that result in deterministic effects at the exposure threshold for the most sensitive effects identified in the scientific literature. For many carcinogens, no threshold level of exposure is recognized, and exposures are managed so that an exposed ndividual will incur an incremental lifetime carcinogenic risk of no more than one-in-one million. The author will present this approach for chemicals and describe how it compares to approaches to manage risk to the public from exposures to ionizing radiation.
Ansari A (Centers for Disease Control and Prevention)
Radiation protection, also known as health physics, is the discipline responsible for the protection of humans and their environment from the harmful effects of ionizing radiation while providing for its beneficial uses. (http://hps.org/students/faq.html). Health physicists are actively engaged in the practice of radiation protection in the nuclear industry; academia; medical and public health systems; local, state and federal government; the military;and other areas. As can be expected, the specific roles and responsibilities of health physicists vary widely across these arenas and occupational disciplines. A common thread that can bind radiation protection professionals together is the professional Society that has served as their professional home for more than six decades. The Health Physics Society (HPS) remains the largest radiation protection society in the world. The mission of HPS, as stated in its 2017 Strategic Plan, is excellence in the science and practice of radiation safety. The core services of the Society are to a) advocate for radiation safety and scientifically sound information, b) provide radiation safety information to the public and government, c) support academic programs and students, d) provide continuing education for radiation safety professionals, and e) collaborate with international radiation safety organizations. In many ways, radiation protection professionals, on an individual level, strive to perform the same functions as part of their duties and practice of their profession. One of the most fundamental functions of radiation protection professionals is the evaluation health and risk information. This communication is often with co-workers and managers, sometimes with students, and most importantly with members of the public. Communication with members of the public may be through an intermediary (e.g., the media), or it can be direct for those health physicists who are on the front lines of the practice with direct contact with the public. As the foundation of our radiation protection practice is based on sound scientific principles, the health and risk messages we communicate also need to be based on the best scientific information available. The credibility of our profession depends on it.
What Every CHP Should Know About ....
Wahl, L.(HPS Web Ops)
Everyone can write, yes? And everyone believes that they are better-than-average communicators. But do we write as clearly, gracefully, and effectively as we could? Well, maybe not always. This presentation summarizes what the author has learned after 30 y of writing and editing scientific and technical documents, first as a degreed technical writer/editor, later as a certified health physicist at national laboratories, and now full circle as a technical writer/editor for Health Physics Society (HPS) Web Operations. This presentation draws on style guides both classic and modern, emphasizing particularly the HPS Web Operations’ preferred style. Discussion topics include techniques used by the best science writers, what constitutes plagiarism and how to avoid it, overcoming the curse of knowledge, grammar ‘rules’ that are meant to be broken, writing for the public (as in HPS’s “Ask the Experts” feature), and much more. Principles of good technical writing are illustrated with concrete examples and put into practice with challenging exercises. Participants are invited to bring their own experiences with particularly tricky writing problems so we can discuss and possibly resolve them.
Jenkins, P.(Bowser-Morner, Inc.)
Because radon (222Rn) and its short-lived progeny emit three types of radiation (alpha and beta particles and gamma rays), it is possible to measure radon in air by a number of different methods and devices. These devices are broken into two major categories; ‘passive,’ meaning that no line power or batteries are used; and ‘active,’ meaning that a source of power is required. The ‘passive’ devices are further broken into three categories. The first is based on the use of activated carbon to adsorb radon from the air. These devices are further broken into two categories depending on the technique used for analysis; gamma-ray spectroscopy or liquid scintillation spectroscopy. With gamma-ray spectroscopy, the gamma-rays emitted by two of the short-lived progeny of radon, 214Pb and 214Bi, are detected typically using a NaI detector. With liquid scintillation spectroscopy, the alpha particles emitted by radon, 218Po and 214Po are detected and possibly also beta particles emitted by 214Pb and 214Bi. The quantity of adsorbed radon is a measure of the average radon concentration in the surrounding air during the exposure period. Charcoal devices are used for measurements of 2 to 7 d duration. The second ‘passive’ category is alpha-track devices. A plastic material, usually allyl diglycol carbonate, is mounted inside a filtered chamber made of a conducting material. An alpha particle emitted by radon, 218Po or 214Po, passing through the plastic produces a damaged volume which, when etched in a caustic solution, forms a track large enough to be visualized using a microscope. The observed net track density divided by the exposure duration is a measure of the average radon concentration over the exposure period. Alpha-track devices are typically used for long-term measurements of a few weeks to one year. The third category of ‘passive’ devices is electret ion chambers. A positively charged electret is mounted onto or inside a filtered chamber made of a conducting material. Radon that diffuses into the chamber emits alpha particles, as do two of its progeny, 218Po and 214Po. The alpha particles produce ionization in the air in the chamber, and the resulting free electrons are attracted to the surface of the electret and cause it to discharge. A measure of the decrease in surface potential of the electret and the exposure duration are used to calculate the average concentration of radon in the surrounding air during the exposure time. Beta particles and gamma rays are minor contributors to the total ionization. A correction for ambient gamma background is included in the calculation. Depending on the design of the chamber and the electret, this type of device can be used for an exposure period of between 2 d and 1 y. All ‘passive’ devices must be analyzed subsequent to the exposure. The ‘active’ devices are known as Continuous Radon Monitors (CRMs). These devices are also broken into three categories depending on the type of detector used. The first category uses a scintillation cell. The interior of the cell is coated with ZnS, which scintillates when an alpha particle from radon, 218Po or 214Po strikes it. Depending on the design, radon may passively diffuse into the cell, or the surrounding air may be pumped through the cell. The cell is coupled to a photomultiplier tube. An electronic circuit converts the light pulses to counts. The observed net count rate is a measure of the concentration of radon in the cell. The second category of ‘active’ devices uses ion chambers. A potential is applied between the surface of the chamber and a center electrode. Alpha particles emitted by radon, 218Po and 214Po produce ionization in the chamber. The free electrons are collected on one electrode and the positively charged ions collected on the other. The electronics sense a pulse, which is shaped and counted. The net count rate is a measure of the concentration of radon in the chamber. Beta particles and gamma rays also create ionization in the chambers of this category of CRM, but they produce small pulses that are discriminated by the electronics. The third category uses solid-state detectors. The detector is mounted inside a chamber. Typically, an electrical potential between the surface of the chamber and the detector is used to attract radon progeny to the surface of the detector. When alpha particles are emitted by 218Po and 214Po, a large portion of them strike the surface of the detector, creating pulses that are detected, shaped and counted by the electronics. The net count rate is a measure of the concentration of radon in the chamber. With some detectors, only gross alpha counting is possible. With more sophisticated detectors, it is possible to perform alpha spectroscopy and thus identify and quantify the various progeny of radon and thoron (220Rn). CRMs typically store hourly average measurements, although some models allow other periods. They are typically used for measurements of 2 to 5 d duration, but some models can be used for longer periods of time. Details of these devices, including the calibration and advantages and disadvantages of each, are discussed in this presentation.
Price, S.(Spruce Environmental Technologies, Inc.)
The U.S. Environmental Protection Agency estimates that 1 in 15 homes in the U.S. have radon concentrations above their Action Level of 4 pCi L-1. While mitigation is described as simple and affordable, proper site characterization, system design and adherence to ANSI standards during installation is necessary to ensure long-term occupant safety and energy efficiency. This presentation discusses common radon entry dynamics, pressure field diagnostics, and system requirements. When using active soil depressurization (ASD) as the primary mitigation method, proper fan sizing ensures that system pressures will effectively prevent radon entry while minimizing air loss from conditioned spaces inside the building. Although ASD is the most common mitigation technique, alternate approaches may be necessary depending on the source of radon and diagnostic testing. Radon prevention should begin during the construction of new buildings, and these techniques will also be discussed. Since the goal of mitigation is to permanently lower the indoor radon concentrations, operation, maintenance, and monitoring (OM&M) plans are essential to long-term system quality. When properly designed, radon mitigation systems can reliably reduce radon concentrations in the structure to less than half of the EPA Action Level (2 pCi L-1) with a budget similar to replacing a major household appliance.
Austin, S.(Plexus Scientific Corporation)
In the early 1950s, the Interstate Commerce Commission (ICC) first established radioactive material regulations limiting the radiation levels that emanate from packages to protect radiation-sensitive cargo; e.g., photographic film, which might be transported with radioactive material packages. By protecting such radiation-sensitive cargo, protection was also provided to the drivers and passengers. In 1961, the International Atomic Energy Agency (IAEA) adopted radioactive material transportation regulations (standards) based largely on those of the ICC. Since then, regulations have changed to account for the transportation of “large sources,” improvement in radionuclide classification, and new packaging design and approval. The packaging and transportation of radioactive material depends on several factors that are fundamentalto many radiation protection activities. It is necessary to have information on the type of radioactive material and activity or concentration present. One needs to know the form (solid, liquid, gas, sealed) of the material and its distribution in the material or item to be shipped. Choice of packaging depends on this information. Once the packaging is chosen, surveys are performed to determine the hazards posed outside the package. Understanding requirements for hazard communication is necessary to assure those handling the packages take appropriate precautions to assure the safety of workers and members of the public. Use of standard radiation protection practices such as containment, contamination control, shielding, distance and emergency response are inherent in developing and implementing a program for the transportation of radioactive material.
After a brief overview of the structure of the two chambers of the U.S. Congress (the Senate and the House of Representatives), a description of their relationship with the President and the Executive Agencies, more attention will be paid to the two types of legislation that the Congress passes. Turning to the Federal Agencies, a brief description of the regulatory process with rule making and its effect will take place. Continuing, an attempt to try to describe the ‘rhythm’ of the Federal Government will be made to include the third branch of government, the Judiciary. Finally, remarks will be made about the potential for citizen participation in the workings of the Federal Government and the potential influence Certified Health Physicists can have on Federal Policy-making on a variety of issues.
A radiological/nuclear incident will result in serious traumatic injuries and large, acute doses to the immediate population. The greatest lifesaving opportunities will be seen in those residing in the moderate damage zone (0.5-1 mile from the epicenter). Damage to infrastructure may limit access for victims and suppliers to acute care facilities, creating a need to locate operational facilities and coordinate transportation. Drastic changes in the daily operations of health care facilities will create confusion, as mass casualties will require triage and definitive medical care. ‘New’ hospital leadership will be quickly established, as an incident command system is implemented. Hospitals will assume new responsibilities, including distribution of medical care across multiple facilities, protection of providers from contamination, provision of ‘expert’ advice to government officials and assumption of a greater role in community support. Health care providers will search for just-in-time information on how to assess and manage radiation contamination and related injuries. A brief overview of the medical management of acute radiation syndrome will be provided. Providers will look to CHPs for guidance on risk (not dose). CHPs must understand the concept of risk, the factors that impact the perception of risk, and the difference between estimated risk and inferred risk. Although their expertise is in dose assessment, including the use of clinical decision guides and derived reference levels, they must be prepared to discuss the risks of contamination of staff, acute injury from radiation and future cancer in virtually all of their communications with providers. Communications with the general public may include optimal timing of sheltering and evacuation, appropriateness of KI, and safety of the food and water supplies. Effective communication with the public can mitigate mass confusion and prevent complete failure of leadership. CHPs will play a critical role in informing our leaders in health care and the government about the risks of radiation released during an acute, large dose incident.
Rhodes, W.(Sandia National Laboratories)
The purpose of this presentation is to introduce the overall risk of malevolent use radioactive sources and the reasons for securing large radioactive sources. Risk concepts will be used to describe the threat, vulnerability and consequences of malicious uses of radioactive material. The technical processes used to select the most important radionuclides to secure and the thresholds of source activity will be briefly described. The presentation will include a discussion on the physical security approaches and techniques that every Health Physicist should know when working on source security issues.
Certified Health Physicists may be called upon from time to time to assist in litigation. They may be asked to serve as consulting experts or testifying experts. In either role, the CHP needs to understand the basic steps in the litigation process and how they can provide valuable assistance in their areas of specialization relevant to the issues in the case. This presentation will describe the types of litigation that may need the services of a CHP, the steps in the litigation process, the CHP’s role in each step of the litigation process, and the pitfalls to avoid. The presentation will include several examples of cases where CHP consultation and/or testimony has been provided. The overall role of the CHP is “teacher:” teaching counsel for whom he/she is working, teaching experts in other disciplines who are also working on the case, teaching the Court (judge, magistrate, hearing officer, etc.), and teaching jurors. The presentation will describe how the role of “teacher” in litigation compares with the usual teaching roles of CHPs.
Note about presentations:
All presentations are UNCLASSIFIED.
Two of the presentations (AM-2, 168 MB and AM-3, 273 MB) have embedded graphics and videos that are very large.
AM-2 uses videos in the Quicktime format.
Walker, S. (Sandia National Laboratories)
This presentation will discuss the basic operation of gun and implosion type nuclear weapons using nondescript weapon designs. The discussion will begin with a review of the basic nuclear properties and mechanisms that support the overall weapon operation. Energy takes various forms in nature, and the presentation will demonstrate how these forms are harnessed for weapon operation. We will review the energy density of important weapon types used throughout human history and compare these against fission and fusion processes. Along the way, we will also discuss important differences between reactors and nuclear weapons. A discussion of weapon effects will be reserved for a separate lecture that is part of this special session.
Potter, C. (Sandia National Laboratories)
When a nuclear weapon is detonated, there are four general categories that occur: prompt radiation, thermal radiation, blast, and delayed radiation or fallout. Each of these effects follows its own timeline and causes damage from its own characteristics. Prompt radiation includes gamma rays and neutrons emitted during the fission process itself. The emission of thermal radiation is a somewhat complicated process. Blast is the shockwave emanated from the explosion. Fallout is the result of activated material and fission products lofted into the atmosphere and subsequently settling out onto the ground. The range of these affects is determined by the nuclear yield and is such that some effects can be overcome by others (e.g., prompt radiation by thermal). This presentation will describe prompt radiation, thermal radiation, and blast with fallout being left to a subsequent presentation.
Buddemier, B. (Lawrence Livermore National Laboratory)
In support of the Department of Homeland Security, Lawrence Livermore National Laboratory has provided detailed consequence modeling to support federal risk assessments and community reparedness activities. In the event of a low-yield nuclear detonation in an urban area, one of most important response tasks will be to minimize the exposure to fallout radiation. Detailed analysis of radionuclide composition and atmospheric dispersion of fallout have recently helped inform federal and national guidance on appropriate response actions. Fallout exposure represents the greatest preventable injury after a nuclear detonation and an understanding of the dynamic spatial and temporal nature of the event, along with the protective value of shelter-in-place options, can result in a significant reduction of casualties.
Stricklin, D.*, Wentz, J., Millage, K., Dant, T., Kramer, K., Blake, P. (ARA, DTRA)
Nuclear weapon detonation scenarios have the potential to impact large numbers of people and result in a wide spectrum of complex injuries. Modeling of nuclear detonation scenarios in modern urban cities has indicated that a large number of combined injuries with survivable exposures involving prompt gamma, neutron, and protracted fallout exposures are likely. This assessment is supported by historical data from Hiroshima that indicates 65-70% of injured persons are expected to have acute injuries that involve trauma and/or burn with significant radiation exposure (Geiger 1964).
However, the types and numbers of injuries anticipated are highly dependent the specific details of the scenario and urban features. The health impacts of radiation-combined injuries are associated with faster onset of symptoms, exacerbated symptoms, synergistic increases in mortality, and impaired wound healing (Messerschmidt 1965). The impact of combined injury, protracted fallout exposures, inhomogeneous and partial body exposures, and potential cutaneous doses will complicate assessment and treatment of patients. A detailed overview of potential injuries from nuclear weapon detonation scenarios is provided; this overview was developed using insights from historical case studies, along with modeling analysis involving modern urban environments. The implications of these injuries on diagnostic, treatment, and medical response needs will also be discussed.
Brooks, A.*, Church , B. (Washington State University, BWC Enterprises Inc)
As down-winders from the St. George, Utah, area, the authors have been very concerned about the potential health effects from Nevada Test Site fallout. We invested our early education in the field of Radiation Ecology and were actively involved in following the fallout radionuclides from the nuclear weapons tests through the food chain into man. This early experience triggered a concern about the health impact of fallout in which we have invested our lives. This presentation will review the radiation ecology of fallout in Utah, dose, and target organs for the important radionuclides 90Sr, 137Cs, 131I and 239Pu. Next, we will review the research linking the fallout data to biological changes, including the induction of chromosome aberrations and cancer from these same radioactive isotopes. The very large amount of activity required to induce biological changes will be compared to activity detected in fallout. Finally, the basis for government payment for those who lived in the ï¿½fallout areaï¿½ and developed cancer will be reviewed. Using data from the fallout patterns at the time of the bomb tests, the total activity will be determined and reviewed. From this information the activity and dose received in these high fallout areas will be compared to the areas where people are compensated by the government. The serious disconnects between exposure/dose, risk, and compensation will be provided to show that reimbursement is based strictly on politics and not science.
Brackett, E.*, Smith, M. (MJW Corporation, Dade Moeller)
Personnel monitoring has evolved since the early days of the weapons complex. Procedures, instrumentation, and regulations were being developed as work was progressing. This presentation will review some of the monitoring methods and practices for detecting and assessing internal and external exposures during the first 20 y of the complex. Emphasis will be on the types and frequency of monitoring that was performed at various sites.
Kotsch, J. (U.S. Department of Labor)
The Energy Employees Occupational Illness Compensation Program Act (EEOICPA) was enacted by Congress in October 2000. Part B of the EEOICPA, effective on 31 July 2001, compensates current or former employees (or their survivors) of the Department of Energy (DOE), its predecessor agencies, and certain of its vendors, contractors and subcontractors, who were diagnosed with a radiogenic cancer, chronic beryllium disease, beryllium sensitivity, or chronic silicosis, as a result of exposure to radiation, beryllium, or silica while employed at covered facilities. The EEOICPA also provides compensation to individuals (or their eligible survivors) awarded benefits by the Department of Justice under Section 5 of the Radiation Exposure Compensation Act (RECA).
Part E of the EEOICPA (enacted 28 October 2004) compensates DOE contractor and subcontractor employees, eligible survivors of such employees, and uranium miners, millers, and ore transporters as defined by RECA Section 5, for any occupational illnesses that are causally linked to toxic exposures in the DOE or mining work environment.
Implementation of the EEOICPA involves the coordinated efforts of four federal agencies: the Department of Labor (DOL), Department of Energy, Department of Justice, and the National Institute for Occupational Safety and Health of the Department of Health and Human Services. DOL has primary responsibility for administering the EEOICPA, including adjudication of claims for compensation and payment of benefits for conditions covered by Parts B and E.
Professional Ethics and Health Physics
New Frontiers in Radiation Risk Communication
Petcovic, L. (3rd Order Communications LLC)
The new frontiers of social neuroscience and social psychology suggest a different social context for communicating radiation risk. Traditional risk communication techniques are based on technical expertise and dependent on trust and credibility of both the expert presenter and the presenting institution. A behavioral description would describe traditional communications as Telling and Selling until the audience gets the right answer (as defined by the expert). Yet our Social Brain challenges presentations by experts and reluctantly places trust in institutions.
Our Social Brain is first and foremost relational centric and seeks to identify with other social brains that demonstrate trust in the judgment of the audience, not in the answer. Designed for the Social Brain, three social risk communication techniques will be provided to the PDS audience as
new frontier techniques that first seek to build a relationship, reinforce personal trust, and trust in the Social Brain of audiences.
Brent, R. (Alfred I. duPont Hospital for Children)
Some physicians and other health professionals misinform their patients regarding the magnitude of the risk of environmental toxicant exposure during pregnancy (Brent, 2009; Ratnapalan et al. 2004). Ratnapalan et al. surveyed a large number of general physicians and obstetricians regarding the risk of an abdominal CT scan to a pregnant woman during the sixth week of gestation. Experienced counselors understand that their primary task is to educate the pregnant women or family members concerning the risk of an environmental exposure. The counselor should advise them on the options available, but not on which option to select. On the contrary, in one survey, up to 6% of all physicians would recommend medical termination of pregnancy for women who had undergone a single CT at six weeks gestation, and 27% of all physicians surveyed were uncertain if they would recommend a medical termination of pregnancy (Ratnapalan et al., 2004). In case of a toxicological exposure, the counselor should attempt to establish a good understanding of the exposure in question and its timing. A list of information required to provide high quality counseling to those exposed is listed in the presentation. The pervasive problem is that many physicians and counselors tell the patient or family what to do. In many instances the counselor, 1) has no expertise concerning the risks of an exposure, or 2) the counselor knows the risks; however, he/she does not take the time to educate the patient about the risks.
Toohey, R. (M. H. Chew & Assoc.)
meme was developed by the evolutionary biologist Richard Dawkins to designate a unit of cultural evolution; i.e., an action that spread from an originator to others, such as toolmaking. The concept was later expanded to include ideas that spread from one brain to another (their environment) and compete for success (retention and further transmission) under Darwinian rules; i.e., the memes best suited to their environment will survive and propagate, eventually driving out memes less well-suited.
The resulting science, developed by Brodie, Lynch, Blackmore, and others, is known as memetics, and deals with the propagation of ideas among humans. Given that the human brain is hard-wired for survival by incorporating automatic analyses of sensory inputs for threats and responds accordingly without higher-level conscious processing, memes that convey a threat will naturally survive and prosper in such an environment. This alone explains why the phrase
deadly radiation, has become commonplace in media coverage of radiological issues. Some memes relevant to radiation risk communication include contagion, dread, autonomy, vulnerability, confirmation bias, justice, and others, all of which thrive in human brains much better than do most of the memes of science.
Locke, P. (Johns Hopkins Bloomberg School of Public Health)
The concept of nuclear safety culture came into widespread use in the mid-1980s after the Chernobyl accident. It has been adopted and implemented worldwide. In the United States, the Nuclear Regulatory Commission (USNRC) published a formal safety culture statement in 2011. This policy was adopted after extensive consultation with stakeholders and is intended to apply to all USNRC licensees. Adoption of this policy is voluntary; it is not a regulation and is not enforceable.
Nevertheless, it has been embraced by the nuclear power industry and the Institute of Nuclear Power Operations. According to the USNRC, nuclear safety culture is defined as
… the core values and behaviors resulting from a collective commitment by leaders and individuals to emphasize safety over competing goals to ensure protection of people and the environment. USNRC defines nine traits of a positive safety culture, which include leadership, safety values and actions, personal accountability, respectful work environment, and effective safety communication. This presentation will explain the interdependent relationship between implementation of a positive nuclear safety culture and risk communication. USNRC’s safety culture statement and explanation – as well as almost every other definition of safety culture – makes transparency and openness key attributes. One successful way to foster openness and transparency is through dialogue and the risk communication process. In addition, risk communication can be used to explain the idea of nuclear safety culture and the reasons why the nuclear safety culture’s core values must be adopted and nurtured by all entities that use nuclear materials. Beyond that, however, risk communication is the most direct way to engage members of the public and the regulated community in discussions about how to build a strong and proactive nuclear safety culture.
Becker, S. (Old Dominion University)
In the three years that have passed since the accident at the Fukushima Daiichi nuclear generating station in Japan, many important lessons have been learned. Among the most important have been lessons related to public information and radiation emergency risk communication. In this AAHP presentation, some of the most significant communication lessons from Fukushima Daiichi are highlighted. This includes key communication needs in affected areas, communication and information needs outside of affected areas, and critical communication and information needs among special populations and audiences. After identifying the lessons learned, the presentation traces out their broader implications for radiation emergency preparedness and response.
Bromet, E. (Stony Brook University)
Research following the atomic bombs and the Three Mile Island, Chernobyl, and Fukushima nuclear power plant disasters has found increased and persistent distress, depression, anxiety, post-traumatic stress, and medically unexplained somatic symptoms among affected populations compared to non-exposed controls. In spite of obvious differences among the events, preand post-disaster management, and cultures where they occurred, the emotional responses are remarkably consistent. The highest risk groups have been clean-up workers, evacuees, pregnant women, and mothers of young children. This talk presents (1) descriptive data on the mental health and health risk perceptions of high risk groups, (2) the negative impact of health risk perceptions on mental and physical health, and (3) the iatrogenic effects of physician disaster-linked diagnoses on risk perceptions, health evaluations, and their associations.
Johnson, R.(Radiation Safety Counseling Institute)
Health physicists have long been puzzled and often frustrated about how people can make instant decisions regarding radiation with little or no actual data. Studies in psychology show that our ability to make instant decisions for safety is a part of how our brains are wired for our protection. We are programmed to fear first and think second. We have survived by this innate ability to foresee dangers and take protective actions accordingly.
Instant prediction of danger is not something we do consciously by evaluation of facts or circumstances. For example, if we took the time to analyze whether a nearby snake looks angry and whether it is close enough or fast enough to strike us, it may be too late. Instead our subconscious has automatically responded with an order to our body that says jump back. In fact, we have probably jumped back before we are even consciously aware of the snake at our feet. Our subconscious functions as a superfast computer processing all incoming signals by associations with images and experiences in our memories. Thus we are programmed for instant response without any conscious thought. While this instinct for safety is important for our survival, it is also prone to substantial errors for some dangers, such as radiation. In the process of making decisions for radiation safety, there are at least 15 or more ways that our subconscious is prone to errors relative to the actual circumstances. My studies are showing that even professionals with technical understanding are also prone to errors. This can be demonstrated by the question,
Are your sources of radiation safe? An instant answer to this question can only come from the subconscious because a conscious evaluation of data takes time to process. Also, when asked,
How do you know? the answers invariably come down to beliefs in what we have heard or read about radiation safety. Our subconscious mind is prone to running ahead of the facts to draw coherent conclusions from a few scraps of evidence. Subconscious impressions then become the basis for instant decisions.
Emery, R. (Univ of Texas Houston)
Looking ahead, individuals will most certainly continue to experience apprehensions about possible exposures to radiation both in the workplace and in the environment. These apprehensions can be exacerbated by previously held beliefs, intensive media coverage, and uncontrolled postings on the internet. In the absence of counterbalancing factual information presented in ways individuals can readily comprehend, poor decision making and the wasting of precious public health resources can ensue. So what should health physicists be doing to address situations where incorrect or misinformation abounds? This presentation will discuss the current evidence-based information on risk communications and the techniques that can be employed to possibly counteract misinformation.
Medical Physics and Medical Health Physics - Roles and Responsibilities
S. King, Milton S. Hershey Medical Center
Increasing use of new diagnostic radiology instrumentation and procedures leads to great emphasis on radiation protection of medical personnel. Additionally, optimization of infomation gained from diagnostic procedures in concert with patient dose management is becoming a greater responsibility of diagnostic radiology personnel. Medical physicists and health physicists perform essential functions in radiation protection of medical personnel and patient exposure management. Specific responsibilities of these two professions are separate and distinct in some facilities, but responsibilities may overlap at other facilities.
The roles and responsibilities of medical physicists and health physicists in diagnostic radiology departments will be compared and contrasted. Overall qualifications (education, experience, and certification) of medical physicists and health physicists for specific responsibilities in diagnostic radiology departments will be discussed. Identification of potential problems in diagnostic radiology, assessment of likely consequences, and development of plans to prevent those problems are a part of routine operations of a medical facility. Specific examples of solutions to problems encountered in diagnostic radiology departments will be presented.
R. Vetter, Mayo Clinic
Academic programs in health physics address a myriad of topics associated with the field of radiation science and protection. Prerequisites for entry into academic programs offering degrees in health physics vary from one institution to another. Curricula at institutions awarding degrees in health physics vary and are not standardized. Academic programs in health physics often reside in larger departments, such as physics, nuclear engineering, or radiation biology. Degrees offered by those institutions vary but may include bachelor of science, master of science, and doctor of philosophy.
This presentation will present a comparison of current academic programs in health physics. Requirements for entry into academic programs in health physics will be described. Curricula at academic institutions offering degrees in health physics will be presented and compared. Academic programs that offer specialization in medical health physics will also be described. Specific courses and requirements for completion of medical health physics degrees will be discussed.
D. Hintenlang, University of Florida
Academic programs in medical physics exist at several institutions in the U.S. and Canada. These programs are often associated with multiple colleges in a university setting, thereby bringing together faculty and facilities from multiple academic disciplines. The curriculum for medical physics programs includes specific courses required by CAMPEP, the accreditation program for medical physics academic programs. The medical physics programs currently certified by CAMPEP will be described, including a summary of the current number of students in M.S. and Ph.D. programs. The purpose, duration, and scope of residencies for completio of medical physics dgrees will also be discussed. New academic requirements for medical physics academic degrees to be recognized by the American Board of Radiology (ABR) will be presented, and the impacts of those requirements will be discussed. The creation, purpose, and goals of the newly formed Society of Directors of Academic Medical Physics Programs (SDAMPP) wilil be presented.
M. Miller, Veterans Administration
This presentation will describe certification programs for medical physicists. The term “Qualified Medical Physicist” as defined by the American Association of Physicists in Medicine (AAPM), will be described and discussed. The specific subfields of medical physics for which certification is recognized will be described and discussed. Specific certifying organization for therapeutic medical physics, diagnostic medical physics, nuclear medical physics, and medical health physics will be described. The certification requirements for each of these organizations will be discussed. The history and current status of each certifying organization will be compared. Additional requirements for CHPs to be recognized as certified in the subfield of Medical Health Physics will be described and discussed. Current statistics of active certified medical physicists (in each subfield) will be presented. Qualifications required to be eligible to take the respective certification examinations and the costs of those examinations will also be presented
C. Potter, Sandia National Laboratory
Certification in the field of health physics is awarded by the American Board of Health Physics (ABHP) following successful completion of specific requirements, including minimum professional experience and passing a two-part comprehensive written examinationn. The ABHP currently awards Comprehensive Certification in Health Physics and does not award certifiation in subfields of health physics.
This presentation will describe the current ABHP certification program, including the specific requirements of professional experience and the areas covered by the written examination. Details of each discipline that is addressed in ABHP certification exams will be described. A discussion of examination areas pertaining to medical health physics will be presented. Examples of specific questions included in ABHP certification examinations from prior years will be presented and discussed. The presentation will conclude with a summary of statistics of candidate performance on recent ABHP examinations.
Radiation Protection: How did we get here?; Where should we have gone?
R. Johnson, Dade Moeller Radiation Safety Academy
Where would our profession be if people were not afraid of radiation? Fears have made our profession what it is today. The primary motivation for developments in technology and regulations has been fears of radiation. Fears are the basis of antinuclear sentiments and aversion to nuclear power, nuclear wastes, and especially nuclear bombs. Fears of radiation have moved our profession to very conservative practices in the name of radiation safety. And yet, psychologists know that fear is a good thing as a natural response of our brains for our protection. We have survived as a species by knowing when to be afraid and when to react for safety. Psychologists define fear as an emotional response to a specific stimulus, such as pain or immediate threat of danger. Since radiation does not produce any sensation in our bodies, then our fears of radiation have to be based on imagination. Thus, fear of radiation is not a true fear based on something happening right now, but a manufactured fear based in images of terrible consequences. Our imaginations drive worries and anxieties.
The primary delivery vehicle for radiation fears is the news media. As the wealthiest nation in the world, we also have the luxury of being afraid of virtually everything. Although, it’s hard not to worry when fear is sprayed at us like tear gas from our TV 24/7. The media thrives on telling us of calamities and dangers everywhere in the world, and seems to especially like stories of “deadly radiation.” In fact those words have been used to portray radiation for so long (at least 60 y) that now subconsciously people automatically react to the word “radiation” with aversion. Unfortunately, much of what the media reports is based on radiation mythology (common beliefs which are not technically true). For example, most public concerns are fueled by misconceptions of the LNT model.
Regulators are also driven by fears (what if they are not seen as responsive to scared constituents, what if they do not provide for adequate safety regulations, what if people are harmed from their negligence, etc.?). Health physicists may be driven by fears as well, such as fear of criticism for not doing their jobs well, irresponsibility, carelessness, or neglect. Thus our profession is built around fears. Even the words that describe our work as “radiation safety” imply that there is something to be afraid of, something to be avoided, something for which caution is needed, or something that threatens us.
R. Toohey, ORAU
The International Radiation Protection Association (IRPA) was formed in 1965, as an association of associations. Largely under the impetus of the HPS and Dr. K. Z. Morgan, there were 11 charter associate societies, representing radiation protection (RP) professionals in 16 countries. Since that time, IRPA has grown to 43 associate societies, representing 49 countries, with a total membership of over 17,000.
The goals of IRPA are to promote excellence in the practice of RP and serve as the international voice of the RP profession. IRPA accomplishes these goals by providing mechanisms for those engaged in RP to communicate with each other in order to advance RP throughout the world. IRPA organizes international and regional congresses, encourages the formation of RP professional societies, and encourages international publications, research and education, and the establishment of universally acceptable RP standards.
Recent IRPA initiatives have included the development of a code of ethics for RP professionals, the definition of a radiation protection expert (accepted by the International Labor Organization), and a set of guidelines for stakeholder engagement (adopted as a position of the HPS). IRPA is currently engaged in an international effort to benchmark and promulgate a RP culture that will ensure the transfer of knowledge from those nearing the end of their careers to those just entering the profession, thereby assuring continued excellence in RP.
R. Vetter, Health Physics Society
Shortly after formation of the Health Physics Society (HPS), leaders and members expressed strong interest in responding to a call to influence public policy, including legislation and regulation. This paper describes evolution of the HPS government relations program that was designed with a major objective of assuring that public policy dealing with radiation use and exposure would be based on sound science and good radiation safety practice. Early efforts were conducted by HPS volunteers, but eventually the effort required paid positions. Several examples of government relations work by HPS illuminate how HPS has successfully influenced public policy through the last several decades.
Radiation Protection: How Did We Get Here;
Where Should We Have Gone
Rick Whitman, IUPUI and Purdue
A Historical Perspective is offered regarding Radiation Protection at the US Customs and Border Protection Agency.
M. Boyd, US Environmental Protection Agency
The U.S. Environmental Protection Agency’s (EPA) radiation protection program traces its origins at least as far back as the Atomic Energy Act of 1954 (AEA) and to the Executive Order establishing the cabinet-level Federal Radiation Council (FRC) in 1959. When EPA was formed in 1970 under Reorganization Plan No. 3, the duties of the FRC to “advise the President with respect to radiation matters, directly or indirectly affecting health, including guidance for all Federal agencies in the formulation of radiation standardsï¿½” was transferred to the EPA Administrator.
At this time, the AEA authority to set “generally applicable environmental standards for the protection of the general environment from radioactive materialï¿½” was transferred to EPA from the Atomic Energy Commission (AEC). The AEC retained – and the Nuclear Regulatory Commission (NRC) retains – authority “inside the fence.” The FRC authority is for providing nonbinding guidance, albeit in the form of Presidential Recommendations, and the AEC authority is for setting standards that are to be enforced by NRC and their Agreement States. With the passage of major environmental legislation such as the Clean Air Act, the Safe Drinking Water Act, and the Comprehensive Environmental Response, Compensation, and Liability Act, EPA gained additional standard-setting and enforcement authority over radionuclides in air, drinking water, and soil. Before EPA, the Atomic Energy Commission held authorities now divided among EPA, NRC, the Department of Energy and others.
Understanding this history provides insight into some of the challenges that still arise from these occasionally overlapping authorities.
R. Jones, Retired
Due to the original mission at the Department of Energy (DOE) facilities, the DOE is self-regulated in the area of worker health and safety. Because of its unique authority, DOE has been responsible to develop and establish its own worker health and safety policy and programs, which are then implemented by DOE contractors. Based upon direct management responsibility and technical experience in these programs, the presenter will provide a historical perspective on the influence of politics and science in the shift of the DOE worker radiation protection policy and programs from the DOE Orders system (DOE Order 5480.11), to the development of the DOE RadCon Manual, and eventually DOE rulemaking (10 CFR Part 835). The presentation will also include a historical perspective on the influence of politics and science in the development of the Energy Employees Occupational Illness Compensation Program Act (EEOICPA 2000). Lastly, the expanding role and the influence of politics on the international community’s recommendations for radiation protection policies will be mentioned.
T. Wellock (USNRC) and C. Jones (AFRRI)
It is popular among social scientists to portray America’s science policy as a victim of political and bureaucratic calculation, leading to decisions based on interests rather than evidence. As one political scientist put it, scientific uncertainty and vague regulations allow bureaucrats the wiggle room they need to “justify whatever direction they want to set” when formulating policy. In this interpretation, legitimate science is just a bit player on the policy stage. In reality, the power of science over policy has grown stronger since World War II, as has been the case for the Nuclear Regulatory Commission. Its history of regulating for radiation protection and nuclear power plant safety has been characterized by growing predictability, technical certainty, and public trust in its judgments. This presentation will discuss the historic conditions that have, for the most part, allowed science and technical research to dominate the agency’s regulatory decisions, as well as what its history might indicate for other government agencies.
Radiation Dose Reconstruction for Epidemiology
Gilbert, E.S., National Cancer Institute
The field of radiation epidemiology is distinguished by the large number of studies, and by the extensive efforts that have been made to estimate dose. The availability of estimates of a biologically relevant quantity (dose) makes it possible to quantify dose-response relationships, to evaluate risks in populations that have not been studied, and to compare risk estimates (at a given dose) across subgroups and studies. For example, estimates based on persons exposed at low dose rates (e.g. nuclear workers) are compared with estimates based on persons exposed at high dose rates (e.g. Japanese A-bomb survivors), and estimates based on persons exposed in childhood are compared with estimates based on persons exposed in adulthood. Clearly, it is important that dose estimates be comparable across different exposed groups with organ dose being the usual exposure measure of choice. In addition, potential differential bias in doses of persons who develop diseases of interest (e.g. cancer) compared to persons who do not need to be minimized.
Radiation dose estimates used in epidemiological studies are typically subject to many sources of uncertainty. The impact of dose uncertainties on epidemiologic dose-response analyses and methods to correct for these uncertainties depend on the magnitude and type of error. Thus, understanding the error structure and quantifying uncertainties is an important aspect of the dose estimation process. Adequately addressing dosimetry uncertainties will usually require close collaboration between the dosimetrist and the statistician who performs epidemiologic dose-response analyses.
Ethel Gilbert earned B.A. in mathematics from Oberlin College and a M.P.H. and Ph.D. in Biostatistics from the University of Michigan. She is a biostatistician in the Radiation Epidemiology Branch of the National Cancer Institute. Her current research includes studies of workers at the Mayak nuclear plant in Russia, studies of second cancers after radio- and chemotherapy, and radiation risk assessment. She was a member of both BEIR VI Committee on Health Effects from Exposure to Radon and the BEIR VII Committee on Health Risks from Exposure to Low Levels of Ionizing Radiation.
Napier, B.A., Pacific Northwest National Laboratory
NCRP has prepared a new report, No. 163, on radiation dose reconstruction – which is defined to be the retrospective assessment of dose to identifiable or representative individuals or populations by any means. In the report, the scope of dose reconstruction includes estimates of absorbed dose to individual organs or tissues for specified exposure situations in support of epidemiological studies or compensation programs, to guide interventions in accidental or malevolent exposures, or for individual or public information. The report views dose reconstruction as a process that begins with a defined purpose and objectives, such as determining compensation for past exposures, input to radiation health studies, or testimony in litigation. Dose reconstruction is carried out in a logical and orderly manner. The dose reconstruction process has several basic elements. These elements can be divided into the five essential steps in the dose reconstruction process, and the two foundation elements of the entire dose reconstruction process that are integral to performing each step: 1) definition of exposure scenarios, 2) identification of exposure pathways, 3) development and implementation of methods of estimating dose, 4) evaluation of uncertainties in estimates of dose, and 5) presentation and interpretation of analyses and results. The foundation elements of the dose reconstruction process are data and other information, and quality management. Each element is discussed and the process is illustrated by numerous detailed examples taken from major recent or ongoing dose reconstruction projects.
Bruce Napier has worked in environmental health physics at Pacific Northwest National Laboratory for over 33 years. Bruce was the Chief Scientist for the Hanford Environmental Dose Reconstruction Project, and has been associated with the Department of Energy’s JCCRER Russian projects for over 15 years. Bruce is a member of the National Council on Radiation Protection and Measurements and was Chair of Committee 6-4 on Principles of Dose Reconstruction – the result of which is the topic of his presentation.
Strom, D.J., Pacific Northwest National Laboratory
Classical (measurement) and Berkson (grouping) errors lead to uncertainties in doses that are reconstructed for epidemiology. Management of these uncertainties for radiation epidemiology differs from that for radiation protection dosimetry or for dose reconstruction done in support of compensation decisions. This presentation provides details of computational algorithms for “multiple dose history realizations” for occupational external dosimetry and medical x-ray dosimetry for the Mayak Worker Dosimetry System (MWDS) for use in radiation epidemiology studies. A companion paper by Dr. Alan Birchall and coworkers discusses uncertainties for internal doses. The algorithms include quantitative uncertainty analysis of radiation dosimetry results for gamma, beta, high- and low-LET (linear energy transfer) neutrons and for medical x rays. The algorithm uses a two-stage Monte Carlo approach to manage shared, unshared, and mixed shared-unshared uncertainties. It manages classical and Berkson uncertainties, as well as providing innovative approaches to autocorrelation over time of uncertainty within individual dose histories. The Monte Carlo approach builds on earlier work by Hoffman, Hofer, Napier, Simon, and many others. This approach has not yet solved the problem of creating distributions of “possibly true” doses from which variance due to experimental measurement (classical) uncertainty has been removed, but some progress has been made in this area.
Dan Strom earned bachelor’s and Masters’ degrees in physics from the University of Connecticut, and a Ph.D. in radiological hygiene from the University of North Carolina at Chapel Hill. After beginning his career in operational radiation safety, he was on the faculty at the University of Pittsburgh for 8 years, and moved on to the Pacific Northwest National Laboratory in 1991. His research interests are in applied statistical inference, uncertainties, and dose reconstruction.
Toohey, R.E. Oak Ridge Associated Universities
In the follow-up studies of workers in the luminizing industry, only bone cancers and soft-tissue cancers of the sinuses and mastoids were unequivocally related to the ingestion of radium. In the 1920’s through the early 1950ï¿½s the measured body burden of radium was used as a surrogate for the skeletal dose. In the mid-1950’s to 1960’s, measured body burdens were converted to ï¿½intakesï¿½ with the Norris retention function, a power function equation based on measurements of injection cases from Elgin State Hospital. The published dose-response curves should more properly be called ï¿½uptake responseï¿½ curves, because the parameter used was the initial systemic intake (more properly called the uptake) of Ra-226 plus 2.5 times that of Ra-228, to allow for the greater alpha energy deposited in tissue from the decay chain of the latter. Because there was some question about the number of radium injections some of the Elgin cases actually received, uptakes were recalculated based on the ICRP-20 alkaline earth model in the 1970’s. In 1982 Schlenker modified the ICRP-20 model to allow for exchange with soft tissues, and Rowland modified it further in 1993. The differences are not that great, as at 50 years post intake, the Norris function predicts 0.35% retention, the ICRP-20 model 0.2% retention, and the Modified ICRP-20 model 0.1%. When skeletal doses were calculated, they were usually mean skeletal doses in Gy, i.e., the total alpha energy deposited divided by 7 kg, the total mass of the skeleton. Marshall and Lloyd developed a parameter for endosteal dose, i.e, the dose to the 10-micron-thick layer of cells on endosteal surfaces, equal to 45% of the mean skeletal dose. This roughly corresponds to what ICRP now calls dose to bone surfaces. In fact, the two doses are not very far apart; derivation of a dose coefficient from published systemic uptakes (assuming a gastrointestinal uptake fraction of 0.2) and mean skeletal doses for radium cases yields a value for endosteal dose of 7.5 x 10-6 Sv Bq-1, while the published ICRP 67 dose coefficient for bone surfaces is 1.3 x 10-5 Sv Bq-1. Obviously there are many opportunities to improve the bone surface dose estimates for radium workers and derive risk coefficients comparable to those derived from other studies.
Dick Toohey is the Associate Director of the Independent Environmental Assessment and Verification program at ORAU. He the Past-President of HPS for one more day, and also the Treasurer of IRPA. Before joining ORAU, Dick spent 22 years at Argonne National Lab in both the Center for Human Radiobiology and the ES&H Division.
Alan Birchall (UK Health Protection Agency) speaking for James, A.C., WSU/USTUR
This presentation outlines developments in lung dosimetry for radon daughter progeny since the National Research Council’s 1999 report on “Health Effects of Exposure to Radon: BEIR VI,” including recent progress in ICRP circles towards reconciling the so-called “epidemiological approach” to risk estimation for radon progeny exposure with the otherwise universally applied “dosimetric approach” based on standard biokinetic and dosimetric models. Bringing radon progeny dosimetry (and risk estimation) into congruence with lung dosimetry for all other radionuclides, including the uranium ore aerosol also present in uranium mines and other inhaled actinide materials, would enable the theoretical risks from all of these modes of occupational and population exposure to be compared with on the same metric scales, i.e., absorbed target-tissue dose and dose-rate. This is an old “holy grail” – but maybe it is now nearing “capture.” The presenter gives his own view of what still needs to be done, i.e., “what are the residual uncertainties”?
Dr. Alan Birchall has been working on internal dosimetry for over 2 decades. He is currently Leader of the Biomathematics Group at the U.K. Health Protection Agency, a Fellow of the Institute of Physics, and Adjunct Professor at Washington State University, supporting the U.S. Transuranium and Uranium Registries. Alan has been working on radon since ICRP Publication 32, recognizing the discrepancy between dosimetry and epidemiology. He worked on the ICRP-65 and on the ICRP-66 the respiratory tract model, radon dosimetry for NCRP Report 160, and along with James Marsh is currently calculating radon dose coefficients for ICRP. Dr. Birchall is filling in for Dr. Tony James, whose duties as Director of the USTUR prevented him from attending.
Cullings, H.M., Radiation Effects Research Foundation, Hiroshima, Japan
The main cohort followed by the Radiation Effects Research Foundation (RERF), the Life Span Study (LSS), has 120,321 survivors of whom 93,741 were in the cities at the times of the bombings and the rest are an unexposed control group. Dose reconstruction to date has used a succession of dosimetry systems devised by scientific working groups to estimate doses received directly from neutrons and gamma rays produced by the bombs and debris in the fireballs during the first minute of the explosions. For 86,671 survivors who were incity during the bombings, RERF has calculated doses using the DS02 dosimetry system or extensions of it, e.g., a spline regression for survivors at long distances and estimated transmission factors for survivors who lack full shielding data. DS02 calculates absorbed dose to fifteen organs, separately for neutrons and gamma rays, using a combination of discrete ordinates transport and Monte Carlo methods, along with models of structural and terrain shielding and anthropometric models. In the 1950s and early 1960s interviewers collected detailed data on location and shielding for 22,787 persons (~75% of the cohort at < 1.6 km in Hiroshima and 80% at < 2 km in Nagasaki); less detailed information was collected for others in various surveys. Classical error due mainly to survivor recall of location and shielding is a major component of error, generally considered to have a coefficient of variation ~ 35% to 40%. Several current research projects seek to use information such as sub-cohort biodosimetry to improve understanding of these errors. There are various Berkson errors due to grouping aspects of the shielding calculations, varying considerably among subsets of survivors classified by available shielding data and to a lesser extent precision of location data. Finally, there are systematic errors in the computational methods of the dosimetry system and its general inputs such as estimated hypocenter locations, heights of the explosions, atmospheric humidity, interaction cross sections, etc. The effect of systematic errors on precision of risk estimates has received rather limited attention to date. Efforts are underway at RERF to characterize doses from residual sources, i.e., potential doses to a small portion of survivors from local radioactive fallout or soil activation near the hypocenters.
Harry Cullings has a M.S. in medical physics and a Ph.D. in biostatistics from the University of Colorado, and worked as a health physicist for about 20 years. He was introduced to RERF and its dosimetry through a post-doctoral fellowship at the University of Pittsburgh, through which he worked for the National Research Council’s Committee on Dosimetry for the RERF and went on to employment at RERF and the Dosimetry System DS02 working group. He has worked in the Statistics Department at RERF for about ten years and recently became the Chief of the department.
Thierry-Chef, I., Marshall, M., Fix, J.J., Cardis, E., Bermann, F., Gilbert, E., Hacker, C., Heinmiller, B., Moser, M., Pearce, M.S.; IARC, Consultant, Dade Moeller & Associates, CREAL, NCI, AECL, Bundesamt fï¿½r Gesundheit, University of Newcastle
A large-scale epidemiological study of nuclear industry workers from 15 countries was conducted to provide direct estimates of cancer risk following low-dose protracted exposure to ionizing photon radiation. As part of this study, the study of errors in dosimetry was set up to identify and quantify biases and uncertainties in historical recorded doses. The identification of errors in doses was based on a review of dosimetric practices and technologies in participating facilities. The main sources of errors on doses from “higher energy” photons (100-3000 keV) were identified as the response of dosimeters in workplace exposure conditions, and historical calibration practices.
Exposure conditions in the working environments were evaluated from measurement and expert assessment. The energy and geometry response of dosimeters used historically was obtained from a series of experiments, and biases due to different calibration practices were estimated. Period- and facility-specific estimates of bias and uncertainties in recorded doses were obtained and conversion coefficients from recorded doses to organ doses have been derived taking into account exposure conditions, dosimeter response and calibration factors. A parametric, log-normal error structure model was developed to describe errors in doses as a function of facility and time period. Doses from neutrons and non-tritium internal contamination could not be adequately reconstructed in the framework of the 15-Country study.
Dr. Isabelle Thierry-Chef got her PhD in 2000 for the work she did, at IARC, on the Study of Errors in Dosimetry conducted within the International collaborative Study of Cancer risk among Radiation Workers in the Nuclear Industry. She then worked for the IRSN in France and for NCI, where she was involved in assessment of doses from medical exposures. She came back to the International Agency for Research on Cancer in 2006 and she is now involved in reconstruction of doses on nuclear workers and on patients.
Simon, S.L., National Cancer Institute
This presentation summarizes methods and strategies for historical reconstruction of occupational radiation absorbed doses to organs and tissues to a large cohort of U.S. radiologic technologists who worked throughout the 20th century. The unique cohort is 73% female and received chronic exposure throughout their career. The dose reconstruction supports an epidemiological study of cancer risk underway at the National Cancer Institute. The methods described here estimate annual and cumulative occupational film badge readings to about 110,000 technologists for each year worked during the period 1916 to 2006 and absorbed doses to twelve organs and tissues (red bone-marrow, ovary, colon, brain, lung, heart, female breast, skin of trunk, skin of head and neck and arms, testes, thyroid, and lens of the eye). Film badge estimates are based on more than 1.2 million archival personnel monitoring measurements supplemented by well-researched literature on measurements, methods, and assumptions. Each individual technologist’s annual badge dose reading is estimated as a probability density function and is used to produce multiple realizations of each cohort memberï¿½s annual and lifetime dose using extensive individual survey work history data and taking into account numerous sources of shared and unshared uncertainties. Each film badge estimate is converted to air kerma and then to organ dose using dose conversion coefficients derived for this study to account for temporal changes in key parameters including peak kilovoltage and filtration. We derived organ dose conversion coefficients based on air-kerma weighting of photon fluences from published x-ray spectra. In addition, we derived energy-dependent transmission factors for protective aprons of different thicknesses and used those to modify organ dose estimates according to individual survey responses about the use of protective aprons. We tailor bone marrow dose estimates to individual cohort members by using an individual-specific body mass index correction factor. The models and reconstructed doses presented here represent, to our knowledge, the most comprehensive dose reconstruction undertaken for a cohort of medical radiation workers.
Dr. Steve Simon received a doctorate in Radiological Health Sciences from Colorado State University. Over the years, he has served on the faculty of the University of Utah and of the University of North Carolina-Chapel Hill and directed the Nationwide Radiological Study of the Marshall Islands. Since 2000, Steve has conducted retrospective dose estimation in support of epidemiologic investigations at the National Cancer Institute, NIH. He has been an Associate Editor of Health Physics for 17 years and a member of the NCRP for 6 years.
Bouville, A., Drozdovitch, V., Luckyanov, N., Voillequï¿½, P.G. ; National Cancer Institute, National Institutes of Health, MJP Risk Assessment
The explosions at the Chornobyl nuclear power plant in Ukraine early in the morning of April 26, 1986 led to a considerable release of radioiodines during 10 days. As the major health effect of the accident is an elevated thyroid cancer incidence in children and adolescents, much attention has been paid to the thyroid doses resulting from intakes of 131I, which were delivered within two months following the accident. The thyroid doses received by the inhabitants of the contaminated areas of Belarus, Russia, and Ukraine varied in a wide range, mainly according to age, level of ground contamination, milk consumption rate, and origin of the milk that was consumed.
The National Cancer Institute is involved in two epidemiological studies of thyroid diseases among populations who were affected by fallout from the accident and who were children at the time of the accident. In these studies, which are conducted in parallel in Ukraine and in Belarus, the estimation of individual doses and of their uncertainties is required. In order to keep the uncertainties at a relatively low level, all cohort subjects – about 13,000 in Ukraine and 12,000 in Belarus – were selected among the children whose thyroids had been monitored for gamma radiation within a few weeks after the accident. These measurements provide the basis for estimates of the amounts of 131I present at the times of measurements. Those results, together with models of environmental transfer and metabolism and answers to personal interviews on residence history and dietary habits, lead to the estimation of the thyroid doses. Evaluation and analysis of the uncertainties in thyroid dose estimates are described in the presentation.
André Bouville is a Senior Radiation Physicist at the National Cancer Institute. Born and educated in France, he came to the U.S. about 25 years ago to estimate the thyroid doses received by the American people from iodine-131 released by the nuclear weapons tests that were conducted at the Nevada Test Site. Later on, he became involved in a number of dosimetry studies related to the Chernobyl accident, notably the epidemiologic studies conducted by the National Cancer Institute in cooperation with the governments of Ukraine and of Belarus. André Bouville is a Council Member of NCRP, and was for many years consultant to UNSCEAR and member of Committee 2 of the ICRP.
Why Society Needs Health Physics: Biological Effects and Challenges
Radiological Accidents and Incidents - Lessons Learned?
Steve Rademacher, Ken Groves, John Taschner
Steve Rademacher, Ken Groves, John Taschner
Health Physics Education: Status of Academic Programs, Student Recruitment, Funding and Accreditation
K. Nelson (HPS President-elect)
As our society ages, so does our workforce. The National Science Board in 2003 estimated that 50% of federal science and engineering workers are expected to retire over the next 10 years. Nationally, especially in science and technology fields, there is concern expressed regarding the number and adequacy of trained replacements for those that retire. The Health Physics Society is also concerned about the human capital crisis and commissioned a task force in 2001 to study this trend and the impact it will have on radiation protection professionals across broad employment categories. In this overview, the 4 R’s of a human capital crisis: recruitment, resources, retention and retirement are discussed. Results and recommendations from the Health Physics Society (HPS) Human Capital Crisis Task Force report are also presented. To follow-up on the recommendations outlined in the HPS Human Capital Crisis Task Force report, the HPS-2020 ad hoc committee was created. Results of the ad hoc committee are discussed. Finally, concerns and future opportunities are presented.
W. Bolch (University of Florida)
For several years now, the HPS Academic Education Committee has maintained a survey of U.S. Academic Programs in Health Physics through its Health Phyiscs Education Reference Book. In this presentation, we will review the current status of U.S. health physics academic programs in terms of student enrollment and graduation numbers, faculty and research areas, research funding support, and program areas of focus. Finally, resources for student fellowship and scholarship support will be summarized.
W. Miller, D. Jonassen, M. Schmidt, M. Easter, G. Ionas, R. Marra, R. Etter, and B. Meffert (University of Missouri, Columbia)
In January 2006, the U.S. Department of Labor Education and Training Administration awarded an HJGTI grant to the University of Missouri-Columbia (MU) in response to the urgent need for radiation protection technicians (RPTs) in support of the nuclear energy industry. This RPT curriculum initiative involves input and collaboration among MU’s nuclear engineering and science education programs, with community colleges, nuclear power plants, professional organizations, and other nuclear industry stakeholders. During the initial phase of the project, we analyzed INPO and DOE training objectives. Our analysis showed that, of all learning objectives, 60% focused on memorization, 18% on comprehension of ideas, 18% on application, 3% on analysis, and less then 1% on evaluation of knowledge – with a predominant emphasis on recall of concepts. As part of our needs analysis, we also observed RPTs in work settings in order to determine what tasks RPTs perform and the skills needed to perform them. Given the complexity of the tasks that RPTs regularly perform, our needs analysis and observations indicated that memorization of facts and concepts is an insufficient learning strategy for developing necessary skills. Based on these findings and discussions with industry stakeholders, we designed a six-course, predominately web-based sequence that will be initially implemented at five community colleges around the country who have partnering with regional nuclear power plants to provide authentic internship experiences for the students. The courses, which are benchmarked against ACAD and DOE criteria, are Radiation Fundamentals, Radiological Monitoring, Radiation Dosimetry, Radioactive Materials Handling, Radiological Safety and Response, Radiation Protection (a capstone experience) and the Internship. The resulting new curriculum will help to meet the demand for qualified, skilled workers in nuclear facilities throughout the country.
D. Simpson (Bloomsburg University)
In 1986, as a result of a technology initiative from the Commonwealth of Pennsylvania; Bloomsburg University located in rural Bloomsburg PA, began development of an undergraduate program in Health Physics. The first Health Physics degrees were awarded in 1990 and to date approximately fifty students have graduated from the program. The BU HP program is multi-disciplinary and is administered by the Department of Physics and Engineering Technology within the College of Science and Technology. It includes a strong foundation of science courses in biology, chemistry, and physics; while still providing its students with a broad liberal arts education. Two faculty members whose combined experience includes work at government research labs, Universities and Nuclear Power Plants, serve as instructors. Facilities include two dedicated laboratories containing state of the art equipment including two HPGe systems, a TLD counter, a Liquid Scintillation Counter and numerous other lab and portable equipment. Bloomsburg University HP graduates are employed at local and regional hospitals, universities, power plants, and other related sites throughout the country. The program also cooperates in local activities such as the annual PPL Nuclear Energy Seminar for Teachers program and the Columbia County radiological emergency response team. Last year, the program’s efforts were recognized when it received accreditation in Health Physics by ABET. The goal of the program is to continue to serve eastern PA, as well as the rest of the country, by providing well-educated students in the field of Health Physics who can pursue their careers upon graduation or continue on to further education at the M.S. and Ph.D. level in Health Physics.
D. Peterson and P. Fulmer (Francis Marion University)
The Health Physics major at Francis Marion University was initiated in 1984 by the late Dr. Lynn D. Hendrick and Dr. David Peterson. One initial impetus was that South Carolina generates over 50% of its electrical energy from 7 nuclear reactors. In addition a survey of all the facilities holding radioactivity licenses showed a need for an in-state Health Physics program. Recruiting students to the program is aided by scholarships specifically for Health Physics majors. These scholarships have been made possible by the generous support of the North Carolina and South Carolina Chapters of the Health Physics Society. The Department holds a residential recruiting weekend to which potential high school seniors are invited.
*(Student travel to scientific meetings is also supported by the Department and the University.)
J. Poston, Sr. (Texas A&M University)
Texas A&M University has a full complement of programs in health physics leading to the B.S., the M.S. and Ph.D. degrees in health physics. The undergraduate degree in Radiological Health Engineering (RHEN) features a strong engineering foundation on which courses in health physics are laid. Although other health physics programs are accredited through the Health Physics Society, this program is the only one accredited by the Accreditation BOard for Engineering and Technology (ABET). The M.S. and Ph.D. degree programs follow a more traditional path toward the degrees. These programs feature classes in radiation physics, radiation dosimetry, radiation detection, radiation biology, radiation carcinogenesis, and microdosimetry, to name only a few. Research is a key for the graduate program and, because of our large faculty, it spans a number of areas including aerosol physics, microdosimetry, radiation biology, environmental impacts, internal dosimetry, and radiological terrorism.
K. Higley, S. Binney, S. Reese, and J. Reyes (Oregon State University)
Health Physics education began at Oregon State University in 1963. The program has transitioned from an x-ray technology program to a modern health physics program. Originally housed in the College of Science, the program was moved piecemeal to the College of Engineering and merged with the long standing Nuclear Engineering (NE) program (established in 1957). In 2001 the name of the Department was changed to Nuclear Engineering and Radiation Health Physics (NE/RHP) to better represent the academic programs contained in the department and to bring greater visibility to the research and academic programs in Radiation Health Physics (RHP). OSU is currently one of only eight institutions in the United States that offers degree programs in both nuclear engineering and health physics. Only four of those institutions offer the complete suite of undergraduate and graduate degree opportunities (B.S. M.S. and Ph.D.) in both fields. OSU’s program was accredited in 2003 by the Accreditation Board for Engineering and Technology (ABET) under ABET’s Applied Science Accreditation Commission. OSU’s RHP major offers courses in radiation physics, radiation detectors and instrumentation, radiation safety, nuclear regulations, radiation biology, radiochemistry radioecology, and radiation dosimetry. Many nuclear courses are shared between NE and RHP. There are 163 students in the NE/RHP program, 41% in RHP. Of these, 29 are RHP undergraduates, and 38 are RHP graduate students (60% enrolled as distance students). Recruitment into the undergraduate program utilizes regional contacts as well as “enticing” students from other programs on-campus. Graduate students come to the program due to a variety of factors: word of mouth, regional employers, and, simply, reputation. Graduates from all degrees of the program are heavily sought by employers and have chosen work in the Federal Sector (e.g., US NRC, military, National Laboratories), State government, private industry (e.g., nuclear power plants), and health care.
L. Miller (The University of Tennessee)
The Health Physics Program offered by the University of Tennessee Nuclear Engineering Department (UTNE) was implemented in 1988 through collaborative efforts among UTNE, Oak Ridge National Laboratory, and Oak Ridge Associated Universities (ORAU). The decision was made to first offer courses in the following areas: 1) Radiation Protection, 2) Radiological Assessment, and 3) Nuclear Instrumentation. Courses in Radiation Biology and Radiation Risk were later added to the academic program, and courses on Internal Dosimetry, Uncertainty Analysis, and MARSSIM have been taught on several occasions as special topics. Students who have graduated from The University of Tennessee program are actively involved in medical physics, health physics, management, criticality safety, radiation safety programs, basic research, and a variety of other areas. From the inception of the Health Physics program in 1988, through the mid 1990s, about twenty new students enrolled in the program each year, and all of the courses were taught at ORAU through The University of Tennessee Evening School Program. Enrollments then declined and stabilized at about ten new students each year. The courses on Radiation Protection and Radiological Assessment are offered each year to local students, and they are offered every other year with simultaneous presentations to local and distance students. The Health Physics graduate Nuclear Instrumentation course is offered in conjunction with a Nuclear Engineering undergraduate course on Nuclear Instrumentation with some additional requirements. Radiation Biology is taught every other year, and it is planned to begin offering it as distance course beginning in the fall of 2007. Since the beginning of the UTNE Health Physics Program, 77 Master of Science (MS) degrees and 19 Doctor of Philosophy (PhD) degrees have been granted. During the past several years the rate of graduation is roughly the average established over the past eighteen years. It appears that the enrollment and graduation rates are stabilized and that this level will continue for at least the next several years.
C.S. French, M.A. Tries, and D.C. Medich (University of Massachusetts Lowell)
This presentation is a review the health physics degree programs offered at the University of Massachusetts Lowell. For over thirty years, this program has been one of the national leaders in enrollment and degrees granted. Since 1973, the program has awarded 237 B.S. degrees in Physics with a Radiological Health Physics option, 282 M.S. degrees in Radiological Sciences and Protection (since 1975), 37 Ph.D. degrees in Physics with a Radiological Sciences option (since 1984), and one Ph.D. degree in Biomedical Engineering and Biotechnology with a Medical Physics/Radiological Sciences option (since 2006). The current enrollment is 11 undergraduate students, 25 master degree students, and 22 doctoral students. This review includes a short history of the program, the status of the current degree offerings, the strategies that have been employed to maintain the program and increase enrollment, and program prospects.
Radiation Measurement Instrumentation for HPs – Looking Back at the Past and Looking Forward to the Future
NOTE – the speaker’s visual aids were designed to accompany an oral presentation, and will not convey the same or a complete meaning when read.
These presentations are property of the Author, and may not be copied without their permission. The contact e-mail for each author is given in the following Abstract section. Contact Frazier Bronson for the password, after permission.
Ronald L. Kathren, CHP | email@example.com
Washington State University at Tri-Cities, Richland, WA
The birth and evolution of health physics instruments used in the field is traced with emphasis on portable survey meters and early developments along with a look into the future. The more or less exponential growth and advancement has been fueled by a number of activities and technical advancement and discoveries, including changes in the definition of radiological quantities, units, permissible dose levels and regulations over the years; programs such as the Manhattan District, Civil Defense and the development of consensus standards both by ANSI and international bodies; technological advances such as discovery of the transistor and development of solid state electronics, improved methods of digital display and the computer revolution; and most recently (and especially in the United States) international terrorism. Most interesting perhaps is to compare contemporary field instruments with their ancestral predecessors; while clearly their external appearance has by and large not changed radically, but what is inside has and the modern electronics permit a wide range of highly sophisticated measurements. On the other hand, the detectors, albeit somewhat improved, are by and large the same ones have been used for the past 60 years.
Steve Rima, CHP | firstname.lastname@example.org
The progression from past gamma dose/exposure rate measuring instruments to the current state of the art, and what the future might hold for new instruments, is discussed. Examples of the current state of the art are presented, including key features and how they arrived at where they are. Are the currently-available instruments serving all of the needs of the operational health physicist, or can we go farther and make them even more useful? We’ll gaze into the crystal ball to see where they may be headed, including the ideas, needs, wants and dreams of operational health physicists. What features would the “dream instrument” of the future have if price was not a roadblock and technology could provide us with everything we wanted? What might such an instrument look like? Does the technology exist to manufacture such a “dream instrument,”, and if so, how soon might we be able to see one available for our use?
Vaclav Vylet, CHP | email@example.com
Neutron detection depends on a number of interactions that produce charge particles, e.g. elastic scattering, fission and an number of specific endo- and exo-energetic reactions. Comparing the current crop of neutron instruments with those developed decades ago, it is clear that the underlying detection processes remain the same. However, progress is constantly made in novel applications of traditional detection schemes, miniaturization of electronics and increasingly more sophisticated on-board signal processing.
In the first part of this talk we will provide a quick overview of neutron detection methods, routine and specialized field measurement techniques, and discuss specific challenges in these areas. We will then feature a few selected instruments illustrating the progress and status quo of neutron instrumentation. The last section will contain a wish list of features that could be easily achieved in the near future, e.g. smarter counting algorithms or detector self-check without use of radioactive sources or natural background.
Joseph. J. Shonka, PhD | firstname.lastname@example.org
Shonka Research Associates, Inc.
Contamination measurements form the core of operational health physics measurements at operating nuclear facilities and remain integral for decommissioning of nuclear facilities. Instruments to meet these needs have evolved from the first “Zeus” device (air ionization chamber used for alpha, beta, and gamma) developed during the Manhattan Project era to the microprocessor controlled devices used today. Over the last 60 years, electronics used for these instruments have steadily improved. However, the basic physics of the radiation detectors remains, to a remarkable degree, unchanging (with the exception of solid state devices). A review of available instrumentation and its application is made for both surface and volumetric contamination as a function of radiation type. Performance of a survey requires five elements: a sensor with electronics appropriate for the radiation type, a means for measuring location, a means for displaying and recording data, a platform that supports the equipment and moves it in the area of interest, and a means for analyzing and reporting the data. The developments in all five of those areas are highlighted. The trends in each of those areas are highlighted in order to show the current and future evolution of the state of the art.
Ron Smith, CHP | email@example.com
Westinghouse Savanna River Site
Currently portable gamma spectroscopy equipment utilizes solid detectors that can be categorized in two major classes based on the temperature at which the detector is operated. Generally the detection systems operate at ambient temperatures or are cooled either by a liquefied gas (usually nitrogen) or an electro/mechanical cooler. Packaging of the detectors that operate at ambient temperatures such as sodium iodide (NaI) are usually thought of as hand held instruments weighing only a few pounds making them truly portable. Cooled detectors used in portable spectroscopy systems are mostly high purity germanium (HPGe) detectors. The HPGe systems will include both detector with cooling medium and associated electronics that comprise an operational system. This combination of hardware will easily weigh over twenty pounds. When contrasting these two classes of spectroscopy systems you must understand that nuclide identification is the primary purpose of the equipment. What is the key attribute of a detector that plays a major role in accurate nuclide identification for complex spectra? That question can be answered with a single word, resolution. It’s a well known fact that cooled (HPGe) detectors have superior resolution to that of detectors operated at ambient temperatures. Along with the hardware associated with these spectroscopy systems there is typically a host of software/firmware provided for the user interface. This software is used for system configuration, calibration, spectral acquisition, system diagnostics, and spectral analyses. One of the must useful additions to the software capabilities is the ability to quantify radionuclides via mathematically calculated efficiencies for complex geometries. Considerable software engineering has been focused in this area over the last few years which has resulted in a more intuitive interface for the users as well as being more portable across many computer operating systems. Looking to the future, anticipating what the next generation of portable spectroscopy equipment will encompass is certainly not clear. Many factors are currently influencing the development of spectroscopy systems which focus on the needs of the United States to minimize the possibility of a terrorist attack using radioactive materials. Portable spectroscopy equipment plays a fundamental role in the security of our homeland against this threat. For the most part portable equipment is used by personnel that respond to initial alerts based on intelligences or actual detection alarms. In this role, future ambient temperature detectors need to be developed so they have spectral resolution comparable to or approaching the current HPGe detector resolution. Another possibility is the future development of a light weight compact electro/mechanical cooling system for HPGe detection systems so these systems become more like the current hand held spectroscopy systems. In general, high resolution hand held spectroscopy systems are likely to be developed to enhance our Nations readiness. All of the future spectroscopy systems will be software driven requiring software development. Enhanced or smart software systems will have to be developed with capabilities to identify radionuclides with greater reliability, locate the radiation emission point, image the area about the emission point, reconstruct an unattenuated spectrum from the acquired spectrum, and auto efficiency calibrate in order to quantify the identified radionuclides.
A. C. Lucas, CHP | firstname.lastname@example.org
Nextep Technologies, Inc
Concern for the exposure of workers to radiation followed slowly upon the growth of the professions involved with the utilization of radioactivity and radiation producing machines. Photographic film dosimeters were one of the first to be widely deployed starting in the early 1930’s. The transition to solids in the postwar era was convolved with widespread differences in opinion and influences by national interests. The path to the present, almost uniform, methodology is traced emphasizing some of the most critical forks in the decision tree. The place of photographic film, thermoluminescence, radioluminescence, and optically stimulated luminescence is discussed both from the viewpoint of their evolution and emplacement in today’s monitoring programs. A short list of “also rans” is presented along with critical minor players. Possible future directions in both programs and material science is discussed with the aim of meeting developing requirements for ensuring accurate, sensitive and economical monitoring in an expanding use of radiation in industry, medicine, and energy supply. The possibility of ensuring overall accuracy in predicting risk discussed as a major shortcoming of the present methodologies. The characteristics of a possible rate and dose determining system are discussed with the intent of characterizing repair function in the event of acute exposure.
Sergio Lopez, MGP Instruments (Presenter) | email@example.com
Frederick P. Straccia, CHP, RSCS, Inc.
This presentation focuses on current state-of-the-art electronic dosimetry devices, including detection characteristics and data processing capabilities and applications. Potential improvements to existing technologies, plus new technologies for electronic dosimeters are discussed.
Technical details are presented on electronic dosimetry applications, including advantages and shortcomings, to detect and measure dose and dose rate for external gamma, beta and neutron radiations. Considerations for ‘dose-of-record’ devices are presented, including applications of the Direct Ion Storage (DIS) dosimeter. The presentation also describes some of the difficulties normally found during implementation of an electronic dosimetry program to be considered by new users. Finally, the presentation contains data on use of telemetry systems. Advantages for maintaining exposures ALARA, as well as common problems with telemetry system applications are discussed.
WF Blakely PhD | firstname.lastname@example.org, Armed Forces Radiobiology Research Institute
PGS Prasanna PhD, Armed Forces Radiobiology Research Institute (Presenting author)
RE Goans PhD, MJW Corporation
The current accepted generic multiparameter approach for biological dosimetry includes (a) radioactivity measurements and monitoring of the exposed individual; (b) observation and recording of prodromal signs and symptoms; (c) obtaining complete blood counts (CBCs) with white blood cell differential; (d) blood sampling for the chromosome-aberration cytogenetic bioassay, using the “gold standard” dicentric assay or alternatively the fluorescence in situ hybridization (FISH) translocation assay in cases of prior exposures for dose assessment; (e) bioassay sampling, if appropriate, to determine radioactivity contamination; and (f) use of other available dosimetry approaches. The Biological Assessment Tool (BAT), a radiation casualty management software application available at the AFRRI website (www.afrri.usuhs.mil), was developed to facilitate medical recording and bioassay dose prediction features of this function. Future developments in biological dosimetry are addressing national needs to provide suitable dose assessment and medical triage and diagnoses in the event of a large-scale radiological casualty incident. Use of automated instruments to accomplish sample preparation for the conventional cytogenetic-based bioassays is being developed along with the establishment of reference cytogenetic biodosimetry laboratories and network. Radiation-responsive molecular biomarkers (i.e., gene expression, protein) are being validated and optimized for rapid radiation exposure assessment applications. Use of electron spin resonance (ESR), ultrasound, and optically stimulated luminescence (OSK) technologies are being investigated to provide early-response indicators of radiation exposure. We are currently developing a First-responder Radiological Assessment Triage (FRAT) software application for use on hand-held personal digital assistant devices to analyze clinical signs and symptoms, lymphocyte counts, physical dosimetry, radioactivity, and location-based dose estimates. [Acknowledgement: AFRRI and the National Institutes for National Institute of Allergy and Infectious Diseases, National Institutes of Health (Bethesda, MD) supported this research under work units BD-02, BD-03, BD-06, and BD-10 and research agreement Y1-AI-3823-01 respectively.]
J. Philipson | email@example.com
Bruce Power, Radiation Protection Programs
Personnel Contamination Monitors are an integral component of most Radiation Protection Programs. Such equipment is crucial in ensuring that both workers and members of the public are protected from low levels of radioactive material.
Existing technologies utilize some of the more common forms of radiation detection, including gas filled detectors and scintillators. The use of personnel contamination monitors is widespread and the technology has undergone considerable change over the years in terms of human factors engineering and data manipulation.
Increasing regulatory scrutiny along with a heightened public awareness for ‘radiation’ in general, leaves health physicists with little room for error in terms of hazard control and identification. Today’s health physicists are in need of equipment that not only performs reliably in terms of detection capabilities, but can operate with high capacity factors and are amenable to incorporating modern technologies.
In this talk, we will examine some of the current designs, including their performance, and will take the liberty of speculating on what tomorrow’s designs may look like. In particular, what advances in detection technology and cost saving measures can be integrated into these devices.
James Ely, Ph.D. | James.Ely@pnl.gov
Pacific Northwest National Laboratory
Radiation detection equipment has been deployed at the U. S. borders to prevent the smuggling of a nuclear weapon, material for a nuclear weapon, or a radiological dispersion device. This equipment, along with other radiation detection equipment deployed outside the United States, is helping to prevent nuclear terrorism. There are different types of detectors used in this effort ranging from radiation portal monitors for screening moving vehicles to handheld detectors, personal radiation detectors, and xray imaging systems. The current installed equipment used on the U. S. borders will be reviewed with the advantages and limitations outlined. Next generation detectors with advanced technical capabilities including passive and active interrogation will be discussed as well as some possible entry process modifications to further increase the security of this nation.
Frazier Bronson, CHP | firstname.lastname@example.org
Health Physicists take instruments with them for field measurements of the environment, but they also take samples of the environment back to the laboratory for more detailed analysis. These laboratory instruments that HPs use today mostly all had their start at one of the Manhattan Engineering District and subsequent Atomic Energy Commission facilities or their contract facilities in the ‘40s and early ‘50s. The same instruments were needed both for weapons design and for radiation protection measurements. Alpha/beta proportional counters came from Argonne, which also gave us the liquid scintillation counter, the Multi-Channel Analyzer, and whole body counting. Oak Ridge created the earliest MCAs and most of the analog signal processing electronics. Los Alamos created practical applications of liquid scintillation counting. Princeton developed NaI detectors and Berkeley created the first Germanium detectors. Because of the importance of this instrumentation to the MED/AEC there was a very rapid influx of innovations to these devices throughout the ‘50s and ‘60s, due to the large amount of government funding for such development. During that time, there was also a rapid growth in the number of nuclear instrument manufacturers. Since that time both the amount of government investment into instrument development and the number of nuclear instrument companies has declined substantially. So has the rate of additional innovation. Today, the fundamental technologies used in laboratory instrumentation are not much different than they were in the ‘60s and early ‘70s. To be sure, today’s instruments are faster, smaller, lighter, more reliable, and after correction for inflation considerably less expensive than those of several decades earlier. That is the contribution of commercialization. This presentation will examine the evolution of these common laboratory instruments that HPs use and set the stage for the following speakers to discuss the present capabilities and to muse and perhaps amuse us about what the future might bring.
Radoslav P. Radev, CHP | email@example.com
Lawrence Livermore National Laboratory
An overview of the available today commercial alpha-beta laboratory counting instrumentation as well as continuous air monitors (CAM) for operational health physics is given. Some of the key features of the current “state-of-the-art” alpha-beta counters presented and data processing and analysis are informative as to where the future might be. The health physicists’s instrument needs, the desired technological advancement and the fundamental detection physics constrains are discussed.
* This work was performed under the auspices of the U.S. Department of Energy by University of California, Lawrence Livermore National Laboratory under Contract W-7405-Eng-48.
C. J. Passo, Jr. | firstname.lastname@example.org
PerkinElmer Life and Analytical Sciences
The liquid scintillation analysis technique dates back to the late 1940s. The first commercial instrument became available in the early 1950s. Through the years, the technique has been refined with major advances in the areas of cocktail formulations and instrument versatility and sensitivity. Most notably, advances in cocktail formulations simplified sample preparation since many different sample matrices can now be measured with minimal preparation and increased counting reliability. In addition, the instrument performance has improved with much higher signal to noise response that allows liquid scintillation counters to be used for environmental radionuclide measurements. Routine environmental measurements are now possible because instrument background levels are now in the several counts per minute range. Today, the term liquid scintillation counter is often replaced by the term liquid scintillation analyzer since systems boast such features as a multi-channel analyzer(s), electronic background reduction techniques, and alpha/beta discrimination. Instruments have either a built in or external dedicated modern computer that allows for extensive data storage, networking and enhanced security. Today, there are a relatively few manufacturers. Current product offerings and the features/benefits of the each is discussed here with a look at the possible enhancements or instrument modifications that are likely in the future.
LaCl3 and LaBr3, newly available Ce doped scintillators from Saint-Gobain Crystals (SGC), have unique and exciting properties making them ideal scintillators for general applications at this time. They are denser and faster than NaI(Tl) which has been the workhorse and standard scintillator for many applications. LaCl3 crystals have a relative density of 3.79 and light output of 29 photons/keV. Detector assemblies with PHRs (pulse height resolutions) below 4% are routinely available. LaBr3 has a relative density of 5.29 and a light output of 63 photons/keV. Detector assemblies with PHRs below 3% are available. Both scintillators are about an order of magnitude faster than NaI(Tl) with decay constants of 28 and 16 nanoseconds for LaCl3 and LaBr3 respectively. Counting at extremely high rates is possible with minimal dead time corrections needed even at 1Mcps. Additionally, time resolutions equal to and surpassing that of BaF2 are possible with coincidence resolving times below 300 picoseconds. Another nice feature of both scintillators is the retention of high light output at high temperature. LaBr3 has double the light output of NaI(Tl) at 175ºC and LaCl3 matches and exceeds the light output of NaI(Tl) above 120ºC. One negative: The natural presence of La-138 limits use in ultra-low background applications. These new crystals are available in increasing sizes as growth development continues, currently 3” dia. x 3” long and larger. They are being sold under the trade names BrilLanCe®350 and BrilLanCe®380 for the chloride and bromide, respectively.
Kanai Shah, PhD | email@example.com
Radiation Monitoring Devices
Solid state detectors are an important class of detectors for X-rays, gamma-rays, charged particles and neutrons. A number of detector materials starting from silicon and germanium to wider bandgap compound semiconductors such as cadmium telluride, cadmium zinc telluride and mercuric iodide have been investigated in past and are available commercially. Along with review of these detector materials, various schemes to enhance their performance (particularly, of compound semiconductors) will also be discussed. This includes various electron-only collection schemes that enhance the spectral resolution of compound semiconductors that have poor hole transport. Newer materials such as thallium bromide for gamma-detection will also be covered. Various solid state detector concepts for neutron detection will be covered. Finally, avalanche photodiodes and advances in this area will also be addressed. Implementation of position sensitive designs for silicon avalanche photodiodes will be discussed. In addition to bulk crystal form of detectors, thick films of solid state materials on crystalline or amorphous silicon read-out devices for large area imaging applications will be covered.
Valentin T. Jordanov, PhD | firstname.lastname@example.org
This work presents an overview of the multichannel analyzers based on digital signal processing methods and algorithms. A comparison between the traditional multichannel analyzers and the digital multichannel analyzers is presented. This comparison shows the advantages of the digital signal processing algorithms in improving the throughput rate and enhancing the spectral resolution. Fast pulse-shape sampling and the use of real time digital algorithms allow pulse-shape analysis that was not possible with traditional analog electronics. Examples are shown illustrating the digital pulse-shape discrimination technique. The separation of neutron interactions from gamma interactions in liquid scintillators allows measurement of the dose due to neutrons only as well as the dose due to the gammas only. The application of the digital multichannel analyzers for environmental radiation monitoring is also discussed.
Timothy Lynch, CHP | email@example.com
Pacific Northwest National Laboratory
The current generation of in vivo monitoring instrumentation for radiation protection purposes utilizes solid state detectors with high-purity germanium crystals and scintillation detectors with thallium-activated sodium iodide phosphors for most applications. Single detectors and arrays of detectors are used for the measurements depending on the radionuclides being measured and what part of the body is being monitored. A myriad of instrument configurations are used depending upon the application, funding level, available space and other facility specific issues. For routine monitoring applications the design is intended to optimize placement of the units in close proximity to the body. To illustrate some of the different designs, descriptions are provided of contemporary instrument systems in operation at different facilities around the world. This includes arrays of planar germanium detectors for measurement of low energy photons and coaxial germanium and sodium iodide detectors for measurement of high energy photons. A brief treatment is afforded other types of instruments including phoswich, room temperature diodes, and proportional counters. The salient features of the instruments and systems are highlighted as they pertain to the accurate detection and quantification of radioactive material in the body. After reviewing examples of the current instrumentation, some of the possibilities for what the future of in vivo measurement instrumentation might hold are discussed. Will technology allow even larger germanium crystals to be grown and further increase detection efficiency? Likewise, can room temperature diodes be manufactured with sufficient size and adequate performance characteristics? Can an array of small detectors be worn as a jacket to monitor lung activity and still be stylish? Are organshaped crystals viable? Will segmented detectors help improve detection capability for low energy photons? Or are there other modalities that may become available to help improve the sensitivity and accuracy of in vivo monitoring? Only time will answer these questions definitively but for now we can boldly prognosticate.
Ken M. Kasper, CIH, CHP | firstname.lastname@example.org
Envirocare of Utah, LLC
Radiation detection technologies have changed little over the decades since radiationliberated ions were first detected. The platforms to which the detection systems report have evolved. Today’s microprocessor has been integrated into and has expanded the capabilities of instrumentation. Vast amounts of radiological data can be collected, stored, and then transferred to your desktop computer. Accompanying information can include what, when, how, where, and even the why of the measurements – should you so desire. Communication links like Bluetooth and cellular technologies have also expanded capabilities. Fountains of data can now stream into a computer from points afar. This data can be sorted, filtered, and analyzed faster than a pair of health physicists can agree on a method for calculating a detection limit. The ground rules that shape instrumentation needs have evolved. For example, prior to the License Termination Rule, which provides a uniform and reasonable approach to determining acceptable levels of residual radioactivity, sensitivity was exceedingly important. If there were three radioactive atoms in a sample, we wanted to know. The Bulk Survey for Release process (a.k.a. “green is clean”), which uses in situ gamma spectroscopy, can’t reliably see the three atoms in a container of waste material. The survey process is, however, robust enough to meet the needs of the process and overarching regulations. Technology innovations outside of those related to specific detection methods, and the needs of our industry will likely continue to form the foundation of the next generations of instrumentation.