ENS 44667
ENS Event | |
|---|---|
14:00 Nov 14, 2008 | |
| Title | Brachytherapy Seeds Temporarily Lost And Unaccounted For |
| Event Description | On 10 NOV 08, a patient was admitted for a brachytherapy treatment. The patient received 77.8 mCi of Ir-192 in the form of eight nylon ribbons, each ribbon containing 7 seeds, for a total of 56 seeds (each seed containing 1.39 mCi of iridum-192).
The initial dose rate was 50 cGy/hour with a prescribed dose of 4500 cGy to be delivered over a 90 hour0.00104 days <br />0.025 hours <br />1.488095e-4 weeks <br />3.4245e-5 months <br /> treatment time. On 14 NOV 08 at 0900, when the sources were scheduled to be removed, it was discovered that three ribbons (containing 29.2 mCi of Ir-192) were missing. It was later learned that the ribbons were improperly removed from the room when a physician improperly changed the bandage on the patient (the ribbons were stuck to the bandage with tape). A search was made of the trash compactor located on the back loading dock. The compactor had just been unloaded at 0600 hours0.00694 days <br />0.167 hours <br />9.920635e-4 weeks <br />2.283e-4 months <br /> on 14 NOV 08. A survey of the trash compactor discovered the sources (all three ribbons with all 21 seeds) at 1210 [hrs.] on 14 NOV 08. Hence, the sources were placed in the compactor between 0600 and 0900 on 14 NOV 08. Verification of the sources was visually made by the therapy physicist (the sources did not have serial numbers or other indentifying markings). As a precaution, leak tests were performed on the previously missing sources and the results did not indicate any detectable activity. Based upon interviews of the medical and the housekeeping staff, the following events occurred: a. The physician improperly removed the bandage (and the sources stuck to the bandage with tape) and threw it in the trash can located within the room.. b. The housekeeping staff improperly entered the patient's room and removed the trash from the trash can, placing it in a larger barrel. The barrel was then taken to the loading dock and emptied into the trash compactor. All of this occurred between 0600 and 0900. The compactor is situated in an unoccupied area of the back loading dock (no break areas or smoking areas). c. The maximally exposed individual in this scenario was the housekeeping worker who removed the trash and took it to the compactor on the loading dock: i. The dose rate at one meter from the sources was measured as 13 mR/h. ii. The sources were assumed to be 0.5 meters from the custodial worker. iii. The transit time from the room to the compactor was 20 minutes (based upon interview with the custodial worker). iv. The estimated dose to the worker is 17.3 mRem [based on a provided calculation]. A complete investigation is being made of the incident and will be reported at the next scheduled meeting of the Walter Reed Army Medical Center Radiation Safety Committee currently scheduled for 4 DEC 08. 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. |
| Where | |
|---|---|
| Water Reed Army Medical Center Washington, District Of Columbia (NRC Region 1) | |
| License number: | 08-01738-02 |
| Organization: | Walter Reed Army Medical Center |
| Reporting | |
| 10 CFR 20.2201(a)(1)(i) | |
| Time - Person (Reporting Time:+119.13 h4.964 days <br />0.709 weeks <br />0.163 months <br />) | |
| Opened: | Col. Mark Melanson 13:08 Nov 19, 2008 |
| NRC Officer: | Howie Crouch |
| Last Updated: | Nov 19, 2008 |
| 44667 - NRC Website | |
Water Reed Army Medical Center with 10 CFR 20.2201(a)(1)(i) | |
WEEKMONTHYEARENS 446672008-11-14T14:00:00014 November 2008 14:00:00
[Table view]10 CFR 20.2201(a)(1)(i) Brachytherapy Seeds Temporarily Lost and Unaccounted for 2008-11-14T14:00:00 | |