ENS 42992
ENS Event | |
|---|---|
14:00 Nov 13, 2006 | |
| Title | Leaking Sr 90 Source |
| Event Description | In the process of conducting the semiannual leak tests for sealed sources, a leaking Sr- 90 source was discovered on 11/13/2006. The Sr-90 source is used by the Physics Department in Room 365 of Jadwin Hall. The Sr-90 source has an activity of 180 microcuries and is normally stored in Room 361 of Jadwin Hall. The source actually consists of a foil on which Sr-90 has been electroplated. The foil is situated in a brass cylinder that consists of two cylindrical pieces - the piece in which the foil sits and a collimator end that is usually screwed onto the end containing the foil. When the leak test was conducted 6 months ago, there was no leakage. But after discovering contamination during the leak test on 11/13/06, it was found that a small hole has been punched through the foil so that the foil's integrity is compromised. The last time the source was used was approximately 6 weeks ago, so the damage occurred sometime between May and the end of September. Contamination (less than 150 dpm) has been found on spots on the floor in Room 361 of Jadwin Hall where the source is usually stored. Contamination has been found on a variety of surfaces on which the brass cylinder was set. A very rough estimate of the amount of missing activity is believed to be approximately 25% of the original activity.
No contamination has been found in public spaces. Surveys have been conducted for the two hallways that border the labs in which the source is used (Room 365) and stored (Room 361). Surveys have been conducted in the office of the sole research staff member who uses the source, and the lab in which the source is stored (Room 361). Results from the survey of the hallways and the office show no contamination problem exists in those areas. The wipes from the lab surveyed on 11/14/06 will be available on 11/15/06, but the G-M survey reveals no gross activity other than in the cabinet in which the source is stored and on the floor directly in front of the cabinet. Those areas were readily decontaminated. On 11/15/06, surveys will be conducted in the lab in which the source is actually used (Room 365). Preliminary surveys on 11/14/06 indicated a number of surfaces that are contaminated in that room, and more thorough surveys will be conducted. All suspect areas have been locked and posted. No personal contamination has been discovered. The person who used the source is out of the area and will provided a urine sample when they return. The licensee expects that decontamination will be complete by 11/16/06 and the rooms will have access restored. Licensee has notified NRC R1 (Modes). |
| Where | |
|---|---|
| Princeton University Princeton, New Jersey (NRC Region 1) | |
| License number: | 29-05185-24 |
| Organization: | Princeton University |
| Reporting | |
| 10 CFR 30.50(b)(1) | |
| Time - Person (Reporting Time:+47.75 h1.99 days <br />0.284 weeks <br />0.0654 months <br />) | |
| Opened: | Sue Dupre 13:45 Nov 15, 2006 |
| NRC Officer: | Jeff Rotton |
| Last Updated: | Nov 15, 2006 |
| 42992 - NRC Website | |
Princeton University with 10 CFR 30.50(b)(1) | |
WEEKMONTHYEARENS 429922006-11-13T14:00:00013 November 2006 14:00:00
[Table view]10 CFR 30.50(b)(1) Leaking Sr 90 Source 2006-11-13T14:00:00 | |