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I am grieved to announce the death this morning of the second most severely exposed worker from the JCO criticality accident . See URLs and forwarded article listed below my signature.
-- Valerie Putman
http://www.asahi.com/english/asahi/0427/asahi042707.html
http://home.kyodo.co.jp:80/cgi-bin/searchform
search photographs under "nuclear accident"
http://www.mainichi.co.jp/english/index.html
Please respond to "Dr. Bill Corcoran at NSRC"
To: "Risk Analysis \(list\) Society" Subject: Tokaimura Fatality
Colleagues,
The following link gives the latest on the tragic accident which occurred due to multiple missed opportunities. Important among them was the opportunity to provide workers with adequate mental models of the processes they were assigned to operate. As a former colleague used to say regularly: It is not enough for the people to know how to work the process. They must know how the process works.
http://content.entrypoint.com/content.asp?cid=655875&md5=3e35a7f65a5eeb592abbaaafba54fd2c&bid=1
I had to paste the link into my browser to get it to connect.
For your convenience the article is pasted below the signature area. A Sievert is 100 REM as I recall.
Bill Corcoran
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Source:
From: Valerie L Putman/VPUTMAN/CC01/INEEL/US
Subject: Tokaimura Fatality
Date: April 27, 2000 12:42:06 PM EDT
By Kazunori Takada
TOKYO (Reuters) - A plant worker exposed to massive radiation in Japan's worst nuclear accident died on Thursday, the second victim of an incident that has jolted public confidence in the nation's nuclear power industry.
Tokyo University Hospital officials said Masato Shinohara, 40 -- one of three workers exposed to heavy doses of radiation in the accident last September -- had died of multiple organ failure.
``It is true that Mr. Shinohara has died as a result of the accident,'' one hospital official said.
Shinohara, who was exposed to at least eight sieverts of radiation in the accident at a uranium processing plant in Tokaimura, northeast of Tokyo, was placed on a respirator in February after pneumonia and radiation damage to his respiratory system impaired his breathing, and on a dialysis machine this month after his kidney functions deteriorated.
Last October, he received a transfusion of blood cells from the umbilical cord of a newborn in an effort to stimulate his ability to produce blood cells, which was disastrously damaged by the radiation.
Another worker, Hisashi Ouchi, 35, died in December after being exposed in the accident to 17 sieverts of radiation -- the equivalent of about 17,000 times the average annual normal exposure in Japan.
Experts say seven sieverts is considered a lethal dose.
A third worker who also suffered heavy radiation exposure had recovered and was released from hospital in December.
The Japanese government came under heavy fire for lax supervision of the industry after the accident, which occurred when the workers put nearly eight times the proper amount of condensed uranium into a mixing tank, triggering a nuclear chain reaction.
Saying Shinohara's death had filled him with ``deep regret, Science and Technology Agency chief Hirofumi Nakasone pledged to renew government efforts to prevent such accidents, Kyodo news agency said.
On Tuesday, officials said they had decided to stick with a ''level four'' rating for the Tokaimura accident, despite earlier suggestions that they might raise it one notch to ''level five.''
Level four on the International Atomic Energy Agency's zero-to-seven International Nuclear Event Scale indicates the possibility of a fatal radiation leak at the accident site but no significant risk outside the plant, the official said.
A total of 439 workers and residents were exposed to radiation as a result of the Tokaimura accident.
America's Three Mile Island accident was a level five, while the Soviet Union's Chernobyl accident in 1986 rated a level seven -- the worst nuclear power accident on record.
Japan has a comparatively good record on nuclear accidents, but the Tokaimura case has sparked growing public concern about an industry that supplies some one-third of the nation's electricity needs.
Earlier this month, the government began a one-year review of its nuclear policy.
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Source:
From: Valerie L Putman/VPUTMAN/CC01/INEEL/US
Subject: Tokaimura Fatality
Date: April 27, 2000 12:42:06 PM EDT
TOKYO, April 10 (Kyodo) - A plant worker exposed to an excessive dose of radiation last September in Japan's worst nuclear accident was transferred to a different hospital Monday to receive more generalized care, doctors said.
Masato Shinohara, 40, a worker at a uranium-processing plant run by JCO Co., was moved from the Research Hospital of the University of Tokyo's Institute of Medical Science in Tokyo's Minato Ward to the University of Tokyo Hospital in Bunkyo Ward about 9 kilometers away.
Shinohara arrived by ambulance at the University of Tokyo Hospital at around 11:30 a.m. and was carried to the intensive care unit, the doctors said.
In late February, Shinohara experienced difficulty breathing on his own after contracting pneumonia and suffered internal bleeding in his stomach. He has since been breathing with a respirator.
His condition has stabilized but remains unpredictable and his hospitalization is expected to be prolonged. Doctors had decided to move him to a better-equipped medical institution where he can undergo plastic surgery and rehabilitation.
Shinohara was exposed to an estimated 8 sieverts of radiation at a JCO plant in Tokaimura, Ibaraki Prefecture, on Sept. 30.
His colleague Hisashi Ouchi, 35, died Dec. 21 from multiple organ failure after being exposed to an estimated 17 sieverts.
That level is said to be about 17,000 times the maximum annual permissible exposure in Japan.
Shinohara, Ouchi and a third worker allegedly poured an excess amount of uranium into a processing tank, triggering a self-sustaining nuclear chain reaction.
IBARAKI-Police said today they will file criminal charges against eight employees of JCO Co. over the nuclear accident at Tokaimura last September.
JCO operates the Tokaimura uranium processing plant, which has been closed since the nation's worst-ever nuclear accident.
Plant chief Kenzo Jojima will be indicted for professional negligence, while JCO President Hiroharu Kitani will be held accountable for violating the Law Concerning Regulation of Nuclear Raw Materials, Nuclear Fuel Materials and Nuclear Reactors.
The Sept. 30 accident occurred around 10:35 a.m as workers poured a large amount of uranium solution-for use in the experimental fast-breeder reactor Joyo-into a stainless steel bucket clearly not designed for the procedure. This triggered a nuclear chain reaction that left one worker dead, injured two and exposed more than 400 people to radiation.
Investigators said the Tokaimura plant had been using the buckets to process uranium since 1993 even though it did not have permission to revise processing procedures.
In 1995, Jojima acknowledged before an internal safety inspection committee that buckets were routinely used.
The procedure was adopted into an unofficial manual the following year. It allowed workers to handle seven times more uranium than legally allowed.
Investigators said Jojima almost certainly knew that JCO was violating the law.
Senior officials must be held accountable, police said.
The works supervisor on the site is also suspected of having neglected his duty. Jojima told media personnel after the accident that he could not accurately recall using the buckets and creating the manuals.
MITO -- Police decided Wednesday to file criminal complaints next month against JCO Co., a nuclear-fuel-processing company in Tokaimura, Ibaraki Prefecture, and company President Hiroharu Kitani, 62, for allegedly violating the law regulating the operation of nuclear reactors, in connection with the criticality accident that occurred last September at a uranium-reprocessing plant operated by the company, The Yomiuri Shimbun learned.
This marks the first time that the head of a corporation is to face criminal charges for allegedly violating this law, according to the Science and Technology Agency.
The Ibaraki prefectural police section in charge of investigating the accident is also considering filing similar complaints against others, including Kenzo Koshijima, head of the Tokaimura plant, and the 60-year-old head of the production department on suspicion of professional negligence leading to the death of one operator and the injury of two others. In all, one corporation and nine individuals face criminal complaints. Some may even be arrested, investigation sources said.
The law obliges companies to obtain government approval before making any equipment changes or altering the way nuclear fuels are processed.
According to the investigators, JCO started in January 1993 to use buckets instead of devices approved by the government to produce a uranium solution at the plant.
In September 1995, a committee of safety experts at the company approved the method, although they were aware of its illegality. The procedure was then included in the manual for operators in November that year.
The company also approved, and included in the manual, a process whereby operators were allowed to handle uranium in amounts exceeding the limit for preventing criticality accidents.
On Sept. 30, 1999, the nation's first criticality accident occurred when three operators poured too much uranium into a sedimentation tank that, due to its shape, could not prevent the reaction from taking place.
By law, it was necessary that the series of changes in the equipment and the operational procedures first be approved by the government.
Kitani, who became president in June 1999 and whose duty it was to prevent such illegal acts, is suspected of failing to report the changes and neglecting to pay necessary attention to the situation.
Koshijima, who attended the committee meeting as head of the technical department and was in charge of the handling of nuclear fuels, as well as the head of the production department are also suspected of significant involvement in the illegal operational procedures and failing to correct them though they had the authority to do so, thus setting the stage for the accident.
Kitani said immediately after the accident that he first learned about the illegal procedures from his subordinates on Oct. 1, and added that he should have conducted more thorough safety inspections.
Koshijima said that he could not recall any committee of safety experts, but admitted that he did not fulfill his duties and could not defend himself against criminal complaints if the procedures were determined to be illegal.
Investigators have concluded that several factors in conjunction caused the accident to occur, among them:
-- Operators with no experience in producing highly enriched uranium were not properly trained in safety measures.
-- Safety measures to prevent criticality accidents were seriously flawed.
The investigators concluded that all those facing criminal complaints had neglected their duty to see that such an accident could not occur.
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