Uncleaned Swedish container led to exposure
03 February 2010
An investigation has been launched into how a uranium hexafluoride shipping container was sent from a Swedish fuel facility without having been completely emptied and cleaned. A Urenco employee in Germany was exposed to the material on opening the container.
The exposure occurred on 21 January at Urenco's uranium enrichment plant in Gronau, Germany. Urenco said that there was a minor release of enriched uranium hexafluoride (UF6) when the container was opened, but this was contained within the container preparation room of the plant. The air in the room is filtered so there was no release to the surrounding environment, the company said.
Uranium is only weakly radioactive, and its chemical toxicity - especially when in UF6 form - is more significant than its radiological toxicity. The protective measures required for an enrichment plant like Gronau are therefore similar to those taken by other chemical industries concerned with the production of fluorinated chemicals.
The worker involved in the incident was only exposed to traces of uranium and therefore the radiological contamination was negligible, Urenco said. He was given first aid in Münster and was later transferred to the nuclear medicine department of Düsseldorf University Clinic in Jülich, where doctors treating him said that his general condition was 'very good.'
Urenco said that an investigation of the incident had preliminary concluded that the container concerned contained residual amounts of UF6, "in contrast to the supplier's declaration" that it was "clean and washed out."
The Swedish Radiation Safety Authority (SSM) has now disclosed that the container involved originated from Westinghouse's nuclear fuel assembly plant in Vasteras, Sweden. It said it will investigate the company's internal procedures for cleaning the containers and if any errors were made in the shipment. Westinghouse is to respond within 30 days in writing to explain how the incident occurred and the actions it will take to prevent a similar incident from happening again.
The container involved in the incident was a 30B container used for the transport of enriched UF6. These containers, which can each hold up to 2.27 tonnes of UF6, are subjected to a pressure test every five years to check their integrity. The worker at Gronau was exposed after opening the container prior to it undergoing this pressure test.
Researched and written
by World Nuclear News