CBRN event in Poland on Mon 27th July 2009

The incident has happened during radiography work with Gammamat model TSI-3, containing Ir-192 source with activity at the time 2.6 TBq (70.2 Ci). The technician operating remote crank mechanism was not able to crank in the source to the shielded position. He asked for help company’s radiation protection inspector (RPI). The RPI with the second worker came in the hurry, forgetting to take their individual dosemeters. The RPI had taken his own decision to return the source to the shielded position by manually grapping the guide tube and force the source to move it by gravity to the shielded container. The source was returned back to the safe position. The incident was on July 27th, but information about it was released by the company on 28 September, when the radiation burns of RPI became advanced. The National Atomic Energy Agency (NAEA) Regulatory Inspectors investigated the incident in October and finished investigations in December. There were no doses obtained by the public. The doses of the workers were assessed on the basis of blood test (biodosimetry) and reconstruction of the event, based on the statements of involved workers. The doses of RPI were approximated as: whole body dose 365 mSv and extremity dose about 5 Sv to right hand. The doses of second worker were assessed by biodosimetry examination as whole body dose 182 mSv and extremity dose about 2,3 Sv. The blood tests were performed by Central Laboratory for Radiological Protection in Warsaw from blood samples taken at the beginning of October and repeated at the beginning of November.Final hands dose value of the more exposed worker still remains uncertain.