Japan operator struggling with "highest" radiation level Releads with TEPCO's problems with high radiation levels
Aug 4, 2011, 12:22 GMT
Tokyo - The operator of a damaged Japanese nuclear power plant said Thursday that they are still considering how to deal with high radiation levels that went off the scale of their equipment.
Tokyo Electric Power Co (TEPCO) revealed Monday that more than 10 sieverts per hour of radiation had been recorded on the surface of a pipe located outdoors between reactor 1 and reactor 2 at the Fukushima Daiichi Nuclear Power Station.
The figure was the highest that TEPCO had recorded since the start of the nuclear crisis. But the operator did not know exactly how high it was because their counter went off the scale.
TEPCO cannot deny the level was much higher than 10 sieverts (10,000 millisieverts), Ryo Shimizu, a company spokesman, said.
Shimizu said the company was considering changing its measurement equipment to detect levels higher than 10 sieverts.
If exposed to such a high radiation level in a short period of time, almost anyone would die, experts said.
The operator said radioactive substances might have stuck to the back of the pipe after they were emitted at the beginning of the nuclear crisis when the company vented at reactor 1 to lower pressure, Kyodo News reported.
The plant has leaked radioactive material into the environment since it was crippled by the March 11 earthquake and tsunami. Tens of thousands of residents around the plant have been forced to leave the area.
Shimizu said TEPCO was not measuring everywhere in the complex every day, so it was possible that such high-level radiation could be detected elsewhere.
On Tuesday, more than 10 sieverts per hour were again detected near the scene, TEPCO said. It also said radiation dosages of 5 sieverts per hour were recorded indoors on the second floor of reactor 1, the highest for indoors at the plant.
The figure was measured in front of a pipe in an air-conditioning machine room, TEPCO said. But the dosage may have been larger than 5 sieverts because, it was also off the scale of measuring equipment.
The highest level of radiation detected previously had been 4 sieverts per hour recorded at the floor of the building of reactor 1.
The high doses of radiation were not causing major problems in work to stabilize the troubled plant, Shimizu said.
The Japanese government raised the maximum annual limit for plant workers to 250 millisieverts from 100 millisieverts following the crisis.
Meanwhile, Japanese Prime Minister Naoto Kan Thursday sacked three top government officials in charge of nuclear energy policy, holding them responsible for the handling of the nuclear crisis.
The three officials include Nobuaki Terasaka, head of the Nuclear and Industrial Safety Agency, the regulatory body. The agency was criticised for insufficient safety measures at the Fukushima plant.
They were criticised for insufficient tsunami protection despite repeated warnings. The agency has also been criticised for manipulating public opinion in favour of nuclear power.
The other two officials to be sacked are Kazuo Matsunaga, vice minister for economy, trade and industry, and Tetsuhiro Hosono, head of the Agency for Natural Resources and Energy.