Mathematical models are often used for predicting the environmental transport of radionuclides and other contaminants and for assessing the resulting exposures, doses, and risks that may occur or may have occurred. One of the major approaches used in recent years to address the reliability of model performance is to test model predictions against field measurements, an approach sometimes referred to as "model validation." For models of radionuclide transport in the environment, some of the most valuable model testing opportunities have come about as a result of the Chernobyl accident in April 1986. Several test exercises have been carried out over the last 20+ years under international programs sponsored by the International Atomic Energy Agency, the Swedish Radiation Protection Institute, and other agencies: the Biospheric Model Validation Study, Phases I and II (BIOMOVS and BIOMOVS II), the Co-ordinated Research Programme on Validation of Environmental Model Predictions (VAMP), the Biosphere Modelling and Assessment Methods programme (BIOMASS), and most recently the Environmental Modeling for Radiation Safety Program (EMRAS).


Dr. F. Owen Hoffman, President of Oak Ridge Center for Risk Analysis, organized and served as general chairman of the first international workshop dedicated to the evaluation of mathematical models used to assess the environmental transport of radionuclides and doses to humans. In 1985, he consulted with the Swedish Radiation Protection Institute in cofounding the BIOMOVS program. In 1988, Dr. Hoffman became Chief Scientist to the International Atomic Energy Agency for the VAMP program. He also headed the Multiple Pathways Assessment Working Group of the VAMP program and the Post Chernobyl Data Working Group of the BIOMOVS II program. Dr. Kathleen M. Thiessen, Senior Scientist for Oak Ridge Center for Risk Analysis, chaired the Dose Reconstruction Working Group of the BIOMASS program, and currently chairs the Urban Remediation Working Group of the EMRAS program.. Dr. Thiessen was also instrumental in completing the efforts of the Multiple Pathways Assessment Working Group of the VAMP program and the Post Chernobyl Data Working Group of the BIOMOVS II program. Drs. B. Gordon Blaylock and A. Iulian Apostoaei of Oak Ridge Center for Risk Analysis, have also been active participants in some of the international model validation programs. Drs. Hoffman, Thiessen, Blaylock, and Apostoaei also contributed to the IAEA's Safety Report Series, No.19, dealing with generic models for use in assessing radioactive discharges.


Oak Ridge Center for Risk Analysis has compiled data sets from a number of the international model validation projects. These are available to the scientific public through the Centers for Disease Control and Prevention, Radiation Studies Branch. A summary of the collection and the first several data sets are available in pdf format at the CDC's website: http://www.cdc.gov/nceh/radiation/brochure/profile_intl_projects.htm


Further information on the VAMP and BIOMASS programs, including the IAEA technical reports, is available at http://www-ns.iaea.org/projects/emras/emras-publications.htm. Information about the EMRAS program is available at http://www-ns.iaea.org/projects/emras/

International Model Validation Programs