April 2000

Japan not to upgrade worst nuclear accident

Reuters Japan, April 26, 2000

[Posted 27/04/2000]

The Japanese government decided to maintain the level 4 rating of the Tokai-mura accident.

TOKYO - Japan has decided against upgrading its first fatal nuclear plant accident, sticking to a preliminary rating of "level four" rather than opting for the more serious level five.

A level five was assigned to the 1979 accident at Three Mile Island in the United States.

"We decided on level four for the final rating," a Science and Technology Agency official said on Tuesday.

The government had previously said the accident last September at a uranium processing plant plant in Tokai, 140 km (90 miles) northeast of Tokyo, might be upgraded to level five.

It occurred when workers put nearly eight times the proper amount of condensed uranium into a mixing tank, triggering a nuclear chain reaction.

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.

The Soviet Union's Chernobyl accident in 1986, rated a level seven, was the worst nuclear power accident on record.

Tokyo University Hospital said on Monday that a 40-year-old worker exposed to heavy doses of radiation in the Tokai incident had slipped into serious condition.

"The patient's prognosis is uncertain after he suffered multiple organ failure," the hospital said in a statement. Another Tokai worker died as a result of the accident late last year, while a third who suffered heavy radiation exposure recovered and was released from hospital in December.

A total of 439 workers and residents were exposed to radiation as a result of the accident.

Back to contents