On April 7 ITN ( the Nuclear and Technological Institute), the institution responsible for the interim storage of radioactive waste in Portugal, was contacted by a private company that requested instructions on how to dismantle, handle and transport a radioactive lightning rod (containing a category 5 radioactive source). Detailed instructions were provided by ITN to the company.
On October 4, the lightning rod was finally delivered at ITN. Prompt inspection and measurements revealed that it contained a Ra-226 source; the measured dose rate at contact was 590 ?Sv/h and at 1 meter 12 ?Sv/h.
After proper investigation it was determined that the lightning rod had been dismantled and disassembled one month before delivery at ITN; the radioactive source had been handled with complete disregard for the instructions provided by the ITN and had been stored for about a month underneath an administrative assistant's desk, without any shielding.
A estimation of the dose received by the administrative staff (1 person) exposed to the radioactive source resulted in a dose of 1,8 mSv to the torso and 7 mSv to the legs. The national statutory annual effective dose limit to a member of the public is 1 mSv.
As an additional measure, health examinations of the exposed member of the public will be requested by the occupational health authorities.
Event date: Tue, 04-10-2011