Radiation | Four people were exposed to radiation at the Olkiluoto nuclear power plant in the summer

Four people were exposed to radiation at the Olkiluoto nuclear power plant in June, says the plant’s owner TVO in its announcement.

The accident happened in connection with the repair work of the lifting device, when four workers were exposed to high radiation dose rates.

of TVO communications manager Johanna Aho tells HS that the fuel elements in the water basins of the reactor building are moved with the lifting device.

The lifting capacity of the repaired machine was to be tested with a test element called a “dummy”. It does not contain fuel.

“Now it happened that due to a lack of instructions and communication, one of the experimental elements had a control rod in the reactor, which had been removed during annual maintenance”.

The radiation alarm went off immediately when the element was lifted from the water. It was immediately lowered.

“The situation was very momentary and quick,” says Aho.

of TVO according to the “dummies” can include rods that were in the reactor, i.e. it was not a radioactive part that ended up in the wrong place, but a human error due to insufficient instructions.

The maximum personal radiation dose was 40 microsieverts. According to TVO, it corresponds to the radiation dose received during an eight-hour flight.

According to the Radiation Protection Agency (Stuk), the official annual limit for a radiation worker is 20 millisieverts, i.e. 500 times the amount for the incident in June.

TVO announced the matter only now, because the investigation was completed on Friday. The report was sent to the Radiation Protection Center today.

TVO says that it has changed its instructions in case of similar events. A similar radiation accident has reportedly not occurred in Olkiluoto before.

Stuk communicates in its own announcementthat it next assesses whether the changes made by TVO are sufficient.