25 Mai 2013
May 25, 2013
Initial reaction to radioactive leak in question
The Japan Atomic Energy Agency says negligence in radiation checks caused a delay in reporting nuclear leakage at its laboratory in Tokai Village in Ibaraki Prefecture, northeast of Tokyo.
The accident occurred around noon on Thursday, when a piece of equipment malfunctioned while researchers were bombarding gold with proton beams to generate elementary particles.
The accident created an unexpected amount of radioactive substances. At least 6 workers, aged between 22 and 45, were exposed.
The agency became aware that the facility had been contaminated with radioactive substances around 5 PM on that day, but it only carried out simple tests to measure nuclear substances on the researchers' clothes, and allowed them go home.
It was not until Friday morning that the agency offered internal radiation checks. It has found that the 6 received internal doses of up to 1.6 millisieverts.
More people are expected to be found to have been exposed. The agency is measuring the dosages of those who were at the facility at that time.
It is believed that the nuclear substances leaked out of the facility because exhaust fans were turned on twice after 3 PM on Thursday to lower the radiation dose that had increased in the experiment room.
However, the agency did not measure radiation levels around the facility, and it was not until after 5:30 PM on Friday that workers noticed that the level at the monitoring post next to the facility had risen.
As a result, the agency did not notify the Nuclear Regulation Authority or the prefectural government of the nuclear leakage until around 9:30 PM on Friday, or more than 30 hours after the accident.
The agency has apologized for the delay in reporting the accident to the central and local governments. It admitted that it failed to respond appropriately right after the accident, and says it will verify the problem in detail and study countermeasures.