On May 21, 2012, the shutter on an industrial thickness gauging device (
NDC Infrared Systems model 102) was discovered to be bent so that when closed, it did not adequately attenuate the radiation beam from the device. The facility Radiation Safety Officer removed the gauging device from the production line and secured plate steel over the radiation source to provide supplemental shielding to the same degree as the undamaged shutter. The device was placed in secure storage pending shipment for repair.
The device was shipped to 3M Corporate Health Physics in St. Paul, MN, on May 25, 2012. On May 29, 2012, the device was received and the shutter assembly replaced with an undamaged, spare shutter assembly. The repair was performed by [corporate radiation safety staff] under US NRC Radioactive Materials license no. 22-00057-03. The device was then returned to 3M Springfield.
Conversations between 3M Corporate Health Physics and US NRC Region III (Geoffrey Warren) on May 29, 2012, indicated that this event is reportable under 10 CFR 30.50(b)(2).
Location of event: 3M Springfield, 3211 East Chestnut Expressway, Springfield, MO 65802
Isotope, quantity, chemical and physical form: Am-241, 150 milliCuries on February, 7, 1997, double encapsulated solid source (special form).
The event resulted in no additional exposure to any individual.
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
This source is not amongst those sources or devices identified by the
IAEA Code of Conduct for the Safety & Security of Radioactive Sources to be of concern from a radiological standpoint. Therefore is it being categorized as a less than Category 3 source