On January 28, 2004 a letter was received by
Wisconsin's Radioactive Materials Program, dated January 26, 2004 from state licensee J.K. Display, Inc., 8300 W. Parkland Court, Milwaukee, WI 53223. The letter informed the department that the company could not locate one of the two NDR, Inc., P-2021 Nuclecel-Ionizer air gun devices that it had in its possession..
The missing/loss P-2021 device, serial # A2CL456 was leased from NDR, November 2002 with an activity of 10.0 mCi of Po-210. The static eliminator gun was last used in July of 2003 because it was broken and unusable. Apparently, the connections between the air-hose and device leaked, reducing the gun's ability to produce ionized air. The device was placed in the shop on a shelf for return to NDR, Inc. at termination of the lease.
Polonium-210 has a half-life of 138 days, therefore, if the assay date of November 2003 is accurate, the source has gone through approximately three (3) half-lives. The Po-210 source at this point should have an activity of approximately 1.275 mCi.
The licensee has done an exhaustive search of the shop and offices for the device, but it cannot be located. The most likely possibility, according to the company, is an employee threw out the device.
Corrective actions taken by the company are to instruct their six employees to identify the device(s) and their location at all times and to isolate and store unused device(s) in a secure location.