Lessons Learned: Personnel Contamination Incident
This Lessons Learned incident concerns identifying and addressing gaps in contamination control and emergency response procedures.
On August 13, 2024, at Pacific Northwest National Laboratory, while conducting a mandatory inventory preparation ahead of an Extent of Condition initiative to address prior radiological material tracking issues, a researcher inadvertently introduced contamination to their hands.. This occurred when they opened the outermost layer of a triple-bagged radioactive sample, believing it was safe based on misinterpreted instructions on the accompanying radiological tag and unclear verbal guidance from a pre-job briefing.
Misalignment between official procedure documentation, radiological tag labeling conventions, and practical field interpretation led to the researcher’s decision to open the bag inside the laboratory’s Radiological Buffer Area. The contamination then spread to the researcher’s personal items, and crucially, to a laptop power cord belonging to another researcher, who was observing the inventory process. Despite self-surveying clean and clearing a personal contamination monitor upon exiting, the second researcher unknowingly transported the contaminated item offsite inside their backpack, exposing flaws in contamination control procedures.
The personnel contamination incident at the 325 Radiochemical Processing Laboratory (325RPL) highlights issues related to the handling and tracking of radioactive samples, inadequate radiological safety protocols, and gaps in contamination response procedures.
This event led to elevated contamination levels being detected in an entirely separate building and required emergency response from Radiation Protection staff.
Details
The root causes of the incident stem from procedural and training deficiencies. Radiological tag documentation failed to clearly communicate critical safety information, with inconsistent use of key fields like “Contact RCT prior to opening outer container,” leaving staff to rely on personal interpretation.
Additionally, pre-job briefings tied to the EOC failed to adequately address hazard controls and safety measures for inventory preparation involving radiological materials. Post-event investigation revealed that staff were not updated on revisions to radiological safety protocols introduced after the EOC was launched, leading to a lack of awareness about mandatory PPE requirements and survey protocols for handling older or inherited radiological samples.
Further exacerbating the situation, emergency response procedures within RBAs focused narrowly on known contamination sources but did not account for scenarios where contamination could unknowingly spread through personal items or external articles. This gap in response measures, combined with a lack of complete understanding of the event, Radiation Protection staff were unaware of Researcher 2 being involved in the event. Researcher 2 had left the building before the true extent of the contamination was identified. Radiation Protection staff were made aware of Researcher 2 the following day during the fact gathering meeting.
The event underscores the need for clearer procedural expectations, improved radiological tag labeling conventions, mandatory training updates, and stricter contamination response protocols to minimize risks associated with handling radioactive materials in laboratory environments.
Read more from this Lessons Learned incident here.
Content/image source/credit: DOE OpexShare, “Material Handling/Storage, Radiation Protection,” published June 24, 2025.
