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Radioactivity Group

The Radioactivity Group's mission is to develop, maintain, and disseminate radioactivity standards, develop and apply radioactivity measurement techniques, and engage in research to meet the requirements for new standards.

We continue to lead the national effort, in collaboration with the Department of Homeland Security, to develop standards and protocols for radiation instrumentation for early and emergency responders. We have developed an accreditation program with NVLAP for instrument testing. We are also spearheading the development of ANSI standards and testing protocols for spectroscopic portal monitors, neutron detectors, x-ray and high energy gamma-ray interrogation methods, x-ray imaging, data formats for instrumentation data output, and training standards for responders.

The Group continues to lead an internationally-recognized program for standards in nuclear medicine, providing the national standards for radionuclides used in 13 million diagnostic procedures and 200,000 therapeutic nuclear medicine procedures annually in the US. Primary standards of two radionuclides, 223Ra and 68Ge have been developed. A new initiative, aimed at establishing standards and measurement support to improve accuracy and consistency in quantitative Positron Emission Tomography/X-ray Computed Tomography (PET/CT) and Single-Photon Emission Computed Tomography (SPECT) imaging, is well underway.

The Group's environmental program leads to community in low-level and natural matrix material measurements and standardization, and continues to be heavily involved in the world-wide measurement of environmental-level radionuclide dispersal and contamination through a large number of international intercomparisons and traceability programs and SRMs. A Radioanalytical Emergency Procedures Manual Database has been developed to assist organizations preparing for emergency response.

Revitalization of our basic metrology capabilities has involved extensive work in many areas. In addition to introducing the TDCR method to routine use at NIST, work is also progressing on the construction of second-generation TDCR system. The principle method of primary standardization at NIST is live-timed 4πβ-γ anticoincidence counting. During the past two years, NIST researchers have adapted this method to perform primary measurements on a variety of radionuclides. A new automated ionization chamber has been developed at NIST to measure up to 100 samples with programmable sample queuing, sample handling and measurement parameters.

News and Updates

Projects and Programs

Publications

Primary standardization of Ra-224 activity by liquid scintillation counting

Author(s)
Denis E. Bergeron, Jeffrey T. Cessna, Ryan P. Fitzgerald, Brian E. Zimmerman, Lizbeth Laureano-Perez, Ronald Colle, Leticia S. Pibida, Elisa Napoli
A standard for 224Ra activity has been developed, based on triple-to-double coincidence ratio (TDCR) liquid scintillation (LS) counting. The standard was

Preparation and calibration of a Protactinium-231 reference material

Author(s)
Richard M. Essex, Ross W. Williams, Kerri C. Treinen, Ronald Colle, Ryan P. Fitzgerald, Raphael Galea, John Keightley, Jerome J. LaRosa, Lizbeth Laureano-Perez, Svetlana Nour, Leticia S. Pibida
A 231Pa reference material has been characterized for amount of Pa. This reference material is primarily intended for calibration of 233Pa tracers produced for

Standardization of I-124 by three liquid scintillation-based methods

Author(s)
Denis E. Bergeron, Leticia S. Pibida, Brian E. Zimmerman, Jeffrey T. Cessna, Ryan P. Fitzgerald
A solution of 124I was standardized for activity by 4πβ(LS)-γ(NaI) live-timed anticoincidence (LTAC) counting, with confirmatory measurements by triple-to

Tools and Instruments

Awards

Contacts

Group Secretary