The following information was received via E-mail:
In a letter dated December 20, 2017, the President of Radiology Support Devices (RSD)/Alderson Phantoms reported to the Sacramento office of California Department of Health Services, Radiological Health Branch that 9 (nine) sealed sources were missing. The source activities varied from very low microCi quantities to less than picoCi quantities. It was not recognized that one source met the criteria for immediate reporting until a routine, scheduled inspection by Los Angeles County Radiation Management was performed of RSD.
It was discovered on March 22, 2018 that eight of the nine sealed sources were below the 10 CFR 20 Table C reporting requirements, but one sealed source, 2.89 microCi of Am-241 (North American Scientific; calibration date January 1995, no serial number available) met the NRC 24 hour reportability threshold of 1.0 microCi.
The licensee suspects the sources may have been taken by a previous employee. However, the previous employee has denied taking the sources.
California 5010 Number: 032218
Notified Mexican Government Representatives via E-mail.
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