Staff

is a Professional Engineer and the principal of Sublight Engineering. Trained in electrical engineering, he has 30 y experience, primarily in radio frequency (RF), electrical, and computer engineering. His RF work includes human exposure assessment, wireless network design, and interference assessment and mitigation.

Sublight Engineering specializes in measuring, modeling, providing guidance on, and developing standards for human exposure to RF. Since 2000, Mr. Butcher has been working with industry, government, workers, and members of the public on how to better communicate RF risks and benefits and to update and clarify standards related to RF exposure.

As a Senior Member of the Institute of Electrical and Electronics Engineers (IEEE) and the International Committee on Electromagnetic Safety, Mr. Butcher has helped develop the standards for the safe use of electromagnetic energy in the range of 0 Hz to 300 GHz. He is the co-chair of subcommittee 1 on Techniques, Procedures, and Instrumentation, responsible for C95.3 - IEEE Recommended Practice for Measurements and Computations of Radio Frequency Electromagnetic Fields With Respect to Human Exposure to Such Fields. Under his leadership, both groups have made substantial progress updating these documents.

He also serves on the U.S. National Committee of the International Electrotechnical Commission for TC106: Methods For The Assessment Of Electric, Magnetic, And Electromagnetic Fields Associated With Human Exposure. He is on the board of the Association of Federal Communications Consulting Engineers and is licensed in 12 states.

is the Program Director and an Assistant Professor for the University of Alabama at Birmingham’s Masters in Health Physics program. She also serves as a scientific consultant to Risk Assessment Corporation. In addition to her consulting and academic roles, she is the Editor in Chief of the Health Physics Society’s (HPS) “Ask The Experts,” the society’s most successful public information and outreach endeavor. Dr. Caffrey also serves on the HPS Program Committee, which develops and manages the technical program of the society’s meetings. She has a BS in Nuclear Engineering and a PhD in Radiation Health Physics and Statistics from Oregon State University (OSU). She is also a Certified Health Physicist. Her areas of expertise include dosimetry, statistics, data management and interpretation, and public communication. She is a recipient of the HPS Elda E. Anderson Award for outstanding early career health physicists. In 2019 she was selected as one of 10 recipients of Oregon State’s Council of Outstanding Early Career Engineers. This award is reserved for Oregon State Alumni who have distinguished themselves through professional practice, service to OSU, the profession, or society at large.

is an epidemiologist and biostatistician with EpidStat Institute and a consultant to the NCRP with over 15 y of experience in the design and conduct of epidemiological studies. Dr. Cohen’s areas of expertise include cancer epidemiology, obesity, pharmacoepidemiology, occupational health, and radiation health effects. She has spent nearly 15 y collaborating on epidemiologic studies of worker health in relation to radiation exposure including cohort assembly and tracing as well as statistical modeling. In addition, Dr. Cohen is currently Adjunct Assistant Research Professor of Medicine in the Division of Epidemiology within the Department of Medicine at the Vanderbilt University School of Medicine.

is President of Cascade Scientific, Inc., an environmental consulting firm. Dr. Grogan received her PhD from Imperial College of Science and Technology at the University of London in 1984 and has more than 25 y of experience in radioecology, environmental dose reconstruction, and the assessment of radioactive and nonradioactive hazardous wastes. She first worked at the Paul Scherrer Institute in Switzerland on the performance assessment of radioactive waste disposal for the Swiss National Cooperative for the Disposal of Radioactive Waste (Nagra). Dr. Grogan was actively involved in the early international cooperative efforts to test models designed to quantify the transfer and accumulation of radionuclides and other trace substances in the environment.

Validation of computer models developed to predict the fate and transport of radionuclides in the environment remains a key interest of hers. In 1989 Dr. Grogan returned to the United Kingdom as a senior consultant to Intera Information Technologies before moving to the United States a few years later, where she has worked closely with Risk Assessment Corporation managing the technical aspects of a wide variety of projects that tend to focus on public health risk from environmental exposure to chemicals and radionuclides. Dr. Grogan has served on committees for the National Academy of Sciences, the International Atomic Energy Agency, the U.S. Environment Protection Agency, and NCRP. She co-edited the text book Radiological Risk Assessment and Environmental Analysis published by Oxford University Press in July 2008, and authored the chapter on Model Validation.

is a consultant, currently concentrating on the preparation of scientific reports produced by NCRP in all subject areas. From 1982 to 1995, he was Director, Office of Health Physics at the Center for Devices and Radiological Health, U.S. Food and Drug Administration. He also served in a number of scientific and management positions related to radiation protection during his 33 y career as a Commissioned Officer in the U.S. Public Health Service, from 1962 to 1995. He received a BS in Chemical Engineering (University of Maryland, 1961), an MS in Environmental Engineering (Rensselaer Polytechnic Institute, 1966) and a PhD in Nuclear Engineering (University of Maryland, 1971). His technical work has concentrated on radiation dosimetry, particularly with regard to x rays used for medical diagnosis, epidemiological studies of exposed populations, and public radiation emergencies.

He is a Distinguished Emeritus Member of NCRP (after serving as a Council member for 18 y), and an Emeritus member of Committee 3 (Protection in Medicine) of the International Commission on Radiological Protection [after serving on Committee 3 for 28 y (1985 to 2013)]. He was also a member of the International Commission on Radiation Units and Measurements report committee that produced Report 74, Patient Dosimetry for X Rays Used in Medical Imaging.

holds a higher doctorate (DSc) in Radiation Epidemiology and PhD, MSc and BSc in Physics from the University of Manchester, United Kingdom. Her past work has included involvement with the World Health Organization expert group for assessing the radiation cancer risk in Japan after the 2011 nuclear accident at the Fukushima plant. Some highlights of Dr. Walsh’s research have included papers on analyses of: data from the Life Span Study cohort of Japanese survivors of the World War II atomic-bomb attacks; the development of epidemiological models for thyroid cancer risk in areas affected by the 1986 Chernobyl accident; and the mortality follow-up of German “Wismut” uranium miners. She is an Honorary Visiting Research Fellow in the Medical Physics Group at the University of Zurich, Switzerland and a freelance consultant based in Germany. She is currently involved as a partner, through the University of Zurich, in the European Union EU-CONFIDENCE (Coping with Uncertainty for Improved Modelling and Decision Making in Nuclear Emergencies) project, is a member of the International Commission on Radiological Protection Task Group 91, a member of the German Radiation Protection Commission Wismut steering committee, and a consultant to the European Space Agency.