The following information was received from the
Wisconsin Department of Health Services (the Department) via email:
On January 22, 2025, the Department received a telephone notification that the licensee was unable to locate a vial containing (as of January 1, 2025) 167 microcuries of cesium-137. The source was transferred to the licensee's possession with the return of a leased positron emission tomography-computed tomography (PET/CT) coach on January 25, 2024 and was stored on the coach. The licensee subsequently decommissioned and sold the coach and believed they had removed the source as part of the decommissioning. On January 10, 2025, the licensee's radiation safety officer observed that the source was not listed on inventory records. The licensee contacted the transferor of the source, the new purchaser of the vehicle, and searched their facility. Neither the licensee, transferor, nor the transferee could locate the source. On January 20, 2025, the licensee declared the source lost.
The Department performed a reactive inspection on February 7, 2025. The vial source is an Eckert and Ziegler model RV-137-200U with serial number 1896-16-16 and contained 201 microcuries at manufacture on January 1, 2017.
WI Event Report ID No: WI250001.
THIS MATERIAL EVENT CONTAINS A 'Less than Cat 3' LEVEL OF RADIOACTIVE MATERIAL
Sources that are "Less than
IAEA Category 3 sources," are either sources that are very unlikely to cause permanent injury to individuals or contain a very small amount of radioactive material that would not cause any permanent injury. Some of these sources, such as
moisture density gauges or thickness
gauges that are Category 4, the amount of unshielded radioactive material, if not safely managed or securely protected, could possibly - although it is unlikely - temporarily injure someone who handled it or were otherwise in contact with it, or who were close to it for a period of many weeks. For additional information go to
http://www-pub.iaea.org/MTCD/publications/PDF/Pub1227_web.pdf