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| Start date | Reporting criterion | Title | Event description | System | LER | |
|---|---|---|---|---|---|---|
| ENS 44678 | 18 November 2008 07:00:00 | 10 CFR 20.1906(d)(1) | Leaking Sealed Source | 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) |