ENS 58162
ENS Event | |
|---|---|
15:00 Feb 10, 2026 | |
| Title | Unplanned Contamination |
| Event Description | The following information was provided by the licensee via phone and email:
On February 10, 2026, at approximately 0900 CST, a quality control technician was eluting a Ci Mo-99/Tc-99m generator originally produced on February 3, 2026, with an original activity of 7.5 Ci of Mo-99. The quality control technician dropped the glass vial after the elution was complete, spilling the radioactive liquid on the floor and on top of the metal frame of a hoist. Immediately after the spill, the quality control technician covered the spill with masslinn cloth, exited the laboratory, and performed a whole-body survey using a portal monitor. Health physics was notified of the quality control technician contamination and responded to the event. Health physics escalated the incident to the health physics manager/radiation safety officer (RSO). Health physics personnel found contamination on the lab coat, pants, and shoes of the quality control technician. The contamination levels exceeded the count rate instrument scale. Health physics recorded approximately 4.6 mR/hr on the pants, 3.0 mR/hr on the shoes, and 1.3 mR/hr on the lab coat. Health physics did not identify contamination on the skin of the quality control technician. Health physics also performed contamination surveys of the surrounding areas of the portal monitor and the path the quality control technician walked from the laboratory to the portal monitor. Health physics found approximately 4,000 cpm (40,000 dpm) next to the portal monitor. Health physics did not identify other affected areas with contamination greater than background (i.e., 200 cpm or 2,000 dpm). Health physics temporarily secured the affected laboratory to prevent the spread of contamination. Health physics performed a gamma spectroscopy of the contaminated clothes and identified Tc-99m as the sole contaminant. Mo-99 was not identified as a contaminant, nor was it expected to be present in the eluent liquid. Health physics assessed the spill and initiated the decontamination process. Health physics collected air samples of the immediate area of the spill. Health physics discontinued decontamination when the dose rates and contamination levels did not decrease, indicating that the residual contamination was now fixed to the rough concrete floors. Health physics measured exposure rates of the contamination to be approximately 50 mR/hr and approximately 10,000 cpm removable contamination. At approximately 1330, health physics stopped the decontamination efforts and posted the affected area as a shoe cover area temporarily. After the health physics manager discussed the incident with the director of the radiation safety office on February 11, 2026, the director of the radiation safety office noted that the wrong data was used to initially estimate the total activity. At approximately 1600 on February 11, 2026, the director of the radiation safety office alerted the NRC Region III inspector of the event, Curium's efforts to quantify the activity, and the potential for exceeding the 24-hour notification criterion. A review of the generator's data with the quality control manager and health physics manager was completed at approximately 1700 on February 11, 2026, and the total Tc-99m activity involved in the spill and quality control technician's contamination was estimated to be approximately 1.1 Ci (exceeding the 5x annual limit of intake). |
| Where | |
|---|---|
| Curium Maryland Heights, Missouri (NRC Region 3) | |
| License number: | 24-04206-01 |
| Organization: | Curium |
| Reporting | |
| 10 CFR 30.50(b)(1) | |
| Time - Person (Reporting Time:+28 h1.167 days <br />0.167 weeks <br />0.0384 months <br />) | |
| Opened: | Manuel Diaz 19:00 Feb 11, 2026 |
| NRC Officer: | Adam Koziol |
| Last Updated: | Feb 11, 2026 |
| 58162 - NRC Website
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Curium with 10 CFR 30.50(b)(1) | |
WEEKMONTHYEARENS 581622026-02-10T15:00:00010 February 2026 15:00:00
[Table view]10 CFR 30.50(b)(1) Unplanned Contamination 2026-02-10T15:00:00 | |