Print View Posted on: 07 August 2017
On 25 July 2017 on arrival of a package containing a disused Ir-192 source of 29.6 GBq at the Belgian consignee an abnormal radiation level was detected (alarm of a personal dosimeter at 100 μSv/h triggered at about 1.50 m from the package).The package was immediately shielded with a lead blanket and afterwards placed in a hot cell with sufficient shielding.The package was shipped by air from Caïro to Zurich, and consequently from Zurich to Brussels.The FANC (Belgian Regulatory Body) was notified by the Belgian consignee and went on-site for further investigation the next day. Upon opening the package with adequate manipulators it was found that the source and sourceholder were not placed in the foreseen shielded channel inside the container. Radiation levels that were measured are:- 2.6 mSvh at 1 m from the package,- 55 mSv/h at 5 cm from the source.To estimate the potential dose to the passengers, conservative cargo hold and deck configurations were considered, coupled with the passenger lists. The results show that 19 persons could have received a whole body dose exceeding the limit for public exposure (1 mSv) up to a maximum of 6.6 mSv for the flight from Cairo to Zurich and 7 persons up to a maximum of 3.1 mSv for the flight from Zurich to Brussels.Dose estimations for the handlers at Zurich airport show a maximum dose of 0.22 mSv for one of the handlers. For the handlers at Brussels airport the same values are obtained.The driver (radiation worker) who transported the package from Brussels airport to its final destination received an estimated dose of 0.24 mSv, while the workers at NTPE (also radiation worker) received doses of less than 0.36 mSv.