During decommissioning work, it is considered crucial to assess workers’ internal exposure due to alpha dust, which is dust that includes alpha nuclides. As conventional measurement detectors only measure total radioactivity, they cannot make assessments so promptly.
The environmental monitoring group of the Fukushima Research and Engineering Institute developed what it has called the “YAP Cerium Scintillator,” which boasts approximately eight times the precision of conventional detectors. Cerium is a material commonly used to polish glass.
With the cooperation of the Savannah River National Laboratory (SRNL) of the U.S. Department of Energy (DOE), the institute carried out tests confirming the device’s performance using actual samples of alpha dust, which is difficult to do in Japan.
In addition, tests were conducted using oxide particles, including the isotopes plutonium-238 (Pu-238) and neptunium-237 (Np-237)—two alpha-ray nuclides with different energy levels. Those tests demonstrated the feasibility of on-site identification and measurements.
The research group expects applications to be developed in the medical field as well, given that the new detector enables immediate alpha-ray imaging.
