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| Entered date | Event description | |
|---|---|---|
| ENS 44678 | 21 November 2008 18:04:00 | On the morning of Nov. 18, 2008, routine semiannual ECD (Electron Capture Device) leak tests were conducted in the FRD (Field Research Division) laboratory at 1750 Foote Dr., Idaho Falls, ID. A wipe test on the inlets and outlets of the above source showed the presence of 0.011 microcuries of contamination. The wipe was counted on a Ludlum 3030 Alpha Beta Sample Counter that was specifically calibrated for Ni-63 by the Idaho National Laboratory Health Physics Instrumentation Laboratory. Annual calibration was completed on Nov. 12, 2008. The limit of detection for the instrument was calculated as 0.00031 microcurie of Ni-63. When the high count was observed, the smear was immediately sealed in a ziplock plastic bag. The work area where the wipe was done was immediately checked for contamination. Tools (tweezers, pens, notepad) used, table tops, gloves, and the Ludlum instrument itself were wiped with smears and each one counted. The counts on all smears were much less than the instrument limit of detection indicating zero activity. Once it was established that no measurable contamination was present in the environment, steps were taken to isolate the detector. Immediately after the wipe test was completed, all inlets and outlets were recapped and the detector replaced in the locked cabinet where it had been stored. The detector was then removed from the cabinet again and all six sides of the rectangular housing were wiped with a smear. This was counted and showed zero activity indicating that no contamination was on the outside of the detector housing. The detector was placed in a plastic ziplock bag and put in a paint can. The plastic bag containing the smear that counted high was also placed in the can. The can was closed and the outside wiped and counted, again showing zero activity. Further wipe tests were then conducted on the inside of the storage cabinet where the detector was stored, the tables around the gas chromatograph (GC) where the detector was last used and the interior surfaces of the GC. All counts indicated zero activity. Based on these contamination tests, we believe that all leakage is contained within the device which is isolated in the paint can. There was no exposure to the public and neglible exposure to the personnel conducting the leak tests. The detector had been taken out of service on August 23, 2007. It had passed all wipe tests prior to that date. The detector remains in the paint can in a locked metal cabinet inside the FRD laboratory. It will remain out of service until it can be repaired. We have contacted the manufacturer and other companies and are investigating options for repair of the unit. Source identification: Valco model 140BN Electron Capture Detector (ECD), serial number N206 (General License device, Sealed Source Registry No. TX-658-D-102-G, 5 millicuries Ni-63) |
| ENS 44494 | 16 September 2008 16:36:00 | Two Hewlett Packard (HP) gas chromatographs with three HP Nickel-63 detectors at a source strength of 15 millicuries each were determined to be missing from their stored warehouse (Building #4) at NOAA ESRL laboratory in Boulder, CO by (the licensee) on 29 March 2007. A search was begun with the belief that the sources had been moved or used by someone in the NOAA facility because Building #4 was used as a temporary post office for about one year and (NOAA) boxes may have been moved to other locations on the site. The serial numbers of the missing sources were L1231 and L1941 in an HP model 5890 II GC with serial number 2518A05469, and M2087 in another HP model 5890 II GC with serial number 2518A05471. (NOAA) use(s) the ECDs in a worldwide network to measure atmospheric substances (freons) that destroy stratospheric ozone. The network includes stations at Pt. Barrow, Alaska; Niwot Ridge, Colorado; Mauna Loa, Hawaii; American Samoa, and South Pole, Antarctica. Source serial #s L1231 and L1941 were last wipe tested on 24 July 2001. The GC containing those sources was then retired from service at Niwot Ridge and placed in storage on 20 August 2001. Source serial# M2087 was last wipe tested on 7 February 2000. The GC containing those sources was retired from service from American Samoa and placed in storage. On 9 August 2002, all sources were moved to Building #4 for long term storage. They were not wipe tested further since they were inactive. Building #4 is locked 24 hours, seven days a week, and occasionally left opened during working hours without security monitors or staff members in the storage area. The Boulder DoC campus is guarded with access control, but not fenced in. The following activities were investigated to locate the three missing stored sources: (1). The Department of Commerce Laboratories in Boulder stores all excess property in Building #4 to make it ready for transport to the Denver Federal Center for posting of availability of excess property to all government agencies. If the excess property was not transferred to another government agency over a year period, then it will be sold to general public. The thought was that the shipper had taken the instruments with their sources by accident to the Denver Federal Center. We contacted the shipper and the Denver Federal Center, and both reported that they were never picked up prior to 2007. The procedure also requires that each piece of excessed property be sealed with plastic on a pallet with paper work attached, so this possibility was ruled out in 2007. (2). (The licensee) contacted all current employees in the group to make sure that the sources were not loaned out. Nothing was discovered. (3). (The licensee) contacted all past employees in the group to make sure that they had not borrowed the sources without our knowledge. Nothing was discovered. (4). (The licensee) contacted HP, now Agilent Technologies, to see if anyone reported the instruments with the sealed sources as being serviced. Nothing was discovered. (5). (An employee) of ESRL/GMD contacted all observatory staff and inspected all spares parts at our observatories (except American Samoa) over the past year to see if they were there. This required a year for someone from our group to visit each site, including South Pole since it is only opened three months each year. Nothing was discovered. (6). (The licensee) contacted LabX, a web site where used laboratory equipment is sold, to see if the instruments with the missing sources were sold on LabX. Nothing was discovered. (7). Many members of the NOAA/ESRL/GMD searched the complete DoC site and all rental storage facilities in Boulder were completed on 15 August 2008. Nothing was discovered. (The licensee) concluded that these three sources were lost on 28 August 2008 after investigating all of the leads above. The probable outcome is that the sources and their instruments were moved out of NOAA property in Boulder. They are either misplaced or stolen. (The licensee) only contacted one used instrument web site, LabX, a(n) eBay type service, ---they only providing a listing service. In the used instrument market, these instruments are being sold for as high as $12K each. They are the most expensive items that (the NOAA) group currently stores. They are sealed low level beta sources. There is little or no risk to any individuals that worked with them and they do not create a problem for the public at large. 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. |