Meghan Dieffenthaller is a health physicist who grew up right outside of Oak Ridge, Tennessee, so she naturally was drawn to the nuclear sciences. She earned her bachelor’s degree in biology at the University of Dallas (UD) in Irving, Texas, and master’s degree in radiological health with a health physics specialization at Colorado State University (CSU) in Fort Collins, Colorado. While working on her bachelor’s degree, she had three summer internships at Oak Ridge National Laboratory, where she was first introduced to the field of health physics. While at CSU, she worked as a technical researcher and writer for a TENORM and hazardous waste management company in Englewood, Colorado, and had a summer internship at Idaho National Laboratory. She worked as a health physicist for the Dose Reconstruction Program conducted by the National Institute for Occupational Safety and Health (NIOSH) starting in July 2021, in which she would analyze bioassay records and use the Integrated Modules for Bioassay Analysis (IMBA) program to calculate radiation doses to DOE employees. Meghan has been a health physicist with the Radiation Emergency Assistance Center/Training Site (REAC/TS) since January 2023, training emergency responders, healthcare providers, and health physicists in medical radiation response, both domestically and abroad, as well as providing dose analysis capabilities for radiation emergencies. She has also been on the Health Physics Society Program Committee since 2023. She earned her National Registry of Radiation Protection Technologists (NRRPT) certification in February 2025.

Carol Iddins, M.D., serves as director of the Radiation Emergency Assistance Center/Training Site (REAC/TS). As director, she ensures support to multiple governmental and nongovernmental national readiness agencies, as well as oversees the REAC/TS mission to provide advice to other health care professionals regarding the medical management of ionizing radiation-induced injuries and illnesses. Iddins leads REAC/TS as the United States’ only Collaborating Center for Radiation Emergency Management for the World Health Organization (WHO) and coordinates international response through the International Atomic Energy Agency’s (IAEA) Radiation Assistance Network (RANET) and WHO’s Radiation Emergency Medical Preparedness and Assistance Network (REMPAN).

Iddins has consulted on patients with radiation-related injuries/illnesses and has deployed internationally for RANET to provide subject matter medical expertise. Iddins routinely consults on calls regarding potential and actual radiation exposures, evaluates and participates in radiological/nuclear exercises, and shares her specialized knowledge worldwide at courses and professional meetings. She is a member of the National Council on Radiation Protection and Measurements PAC 3 Nuclear and Radiological Security and Safety Committee.

Iddins earned a doctor of medicine degree at the University of Tennessee Health Science Center and completed her residency training in obstetrics and gynecology at the University of Tennessee. She has practiced obstetrics and gynecology and aerospace/occupational medicine in civilian and military environments.

Iddins is a Diplomate of the American Board of Disaster Medicine and a Fellow of the American Academy of Disaster Medicine, and currently the vice president of the American Academy of Disaster Medicine. Iddins is a decorated U.S. Air Force veteran of Operations Allied Force, Enduring Freedom and Iraqi Freedom.

Brittany Phillips is a Registered Nurse and Advanced EMT at the Radiation Emergency Assistance Center and Training Site.

Mrs. Brittany Phillips began her early career in healthcare as a volunteer for her local fire department in 2011. From 2011 to 2019, she volunteered as a firefighter and Advanced Emergency Medical Technician and gained valuable experiences in Emergency Medical Services. She graduated from Tennessee Technological University with her Bachelor of Science in Nursing in May of 2017. After graduation, she began a job in the Medical/Surgical and Neuro Intensive Care Units at Fort Sanders Regional in Knoxville, Tennessee. Throughout her time in the ICU she worked as a bedside nurse, rapid response nurse (hospital-wide), and Shift Leader. She assisted in training new graduate nurses and helped maintain the skills of other nurses through ICU and hospital-wide skills days. She has a well-rounded line of experience from pre-hospital field care to critical inpatient care and relative teaching and critical thinking skills. Brittany also worked as the Stroke and Sepsis Coordinator for Methodist Medical Center in Oak Ridge prior to joining the team at REAC/TS.

Brittany has spent a lot of time doing community outreach activities including local missions and attended a mission trip during nursing school to a remote village in Belize. During the mission trip, she and some fellow classmates helped to create the first electronic health records in the village of San Benito Poite.

Brittany joined REAC/TS in March 2024 and has since attended several classes and has given a variety of lectures for REAC/TS courses.

Dillon Vogt is a Health Physicist with the REAC/TS team. His career started at the Savannah River Site (SRS) in 2016 as an Associate Health Physicist in the External Dosimetry Department. While working with SRS he helped External Dosimetry switch the entirety of their dosimeters from Panasonic TLDs to Landauer OSLs, began working with 3D printing to develop jigs and tools for research purposes, and began to help with the Internal Dosimetry Department with Bioassay receiving, whole body counting, and lung counting. While at SRS Dillon also took over the Criticality Neutron Dosimetry (CND) program, assembling and monitoring the supply of the sites criticality dosimetry and participated in the 2022 International CND Intercomparison Study at the Nevada National Security Site. Dillon started work with the REAC/TS team in the summer of 2023 as one of their Health Physicists. Since then he has been involved in multiple courses offered by REAC/TS both domestic and abroad.