|FIRE INVOLVING LOSS OF INTEGRITY OF LICENSED CONTAINER
"At approximately 0800 EST on May 13, 2020, a thermal reaction occurred inside a production hot cell during a rubidium dissolution process. The pressure created by the reaction caused the back door of the hot cell to open approximately six inches for a few seconds. Curium employees performing the dissolution process immediately activated the hot cell fire suppression system to put out the fire, closed the hot cell door and placed the production area in a secured state. The open hot cell door released airborne radioactive material to a localized area inside the controlled and posted production area. Six employees that were in the vicinity of the production hot cell presented contamination. Contamination was also found on the floor immediately around the production hot cell.
"Curium's RSO isolated the affected area and used the data collected from personal surveys to preliminarily estimate the potential dose to the six employees and the total activity released from the hot cell. The initial dose estimates indicated that the employee with the highest exposure potentially received approximately 6.5 mrem DDE and <1 mrem CEDE. Urinalysis was performed to confirm the internal exposure and intake. At the time of this report, the urinalysis results are still pending. Analysis of air samples taken in the immediate affected area indicated the presence of Sr-82, Sr-85, Rb-83, Rb-84, and Rb-86. After the performance of contamination surveys, decontamination of affected employees and analysis of samples, Curium employees decontaminated the affected area. After decontamination procedures were completed, the affected area was released for normal operations within the same business day without the need for imposing additional radiological controls or restrictions. Radiological surveys confirmed that there was no detectable release of radioactive material to uncontrolled areas adjacent to the hot cell production area.
"Curium performed a preliminary root cause analysis on May 13, 2020. After completing a preliminary assessment of the dose and release of radioactive materials, Curium reviewed the notification requirements prescribed in 10 CFR 20.2203, 20.2204 and 30.50 and made a determination that neither the immediate nor 24-hour notification requirements were warranted. Curium performed a formal root cause analysis on May 14, 2020. Despite a belief that notification was not required, Curium communicated the incident in good faith to Mr. Jason Draper (NRC Region III) on May 14, 2020 at 1100 EST. After further discussions with Mr. Draper throughout May 14, 2020 and further review of the incident and conditions, Curium personnel made a decision to self-report the incident to the NRC Operations Center as specified under 10 CFR 30.50(b)(4).
"Curium is in the process of finalizing the root cause analysis, finalizing the dose estimates, completing confirmatory actions."