The following summary of information was provided by the licensee via phone and email:
Two tritium exit signs were reported lost or missing during a recent safety emergency lighting audit conducted on April 24, 2025. Despite a thorough internal review and inspection of storage, disposal, and installation records, the devices were unable to be located or disposition verified.
The licensee is in the process of updating all emergency exit signage and lighting. Additionally, they are removing the remaining six (6) self-luminous exit signs from their facility and will return them to lsolite for proper disposal in accordance with regulatory guidelines. To prevent any recurrence, the facility will no longer purchase or utilize self-luminous signage in the future.
The following additional information was obtained from the licensee in accordance with Headquarters Operations Officers Report Guidance:
There is no information of previous inventory records since the initial delivery around April 2016. Information about this event was previously reported to the NRC Region III office on May 12, 2025.
Maker: Isolite
Model Number: SLX-60
Serial Numbers: H56081 and H56088
Estimated Activity: 0.281 TBq tritium (H-3) or 7.59 Ci/ sign (TOTAL: 0.562 TBq or 15.18 Ci)
Date of Manufacture: March 2016
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