Japan's Kansai Electric Power Co said it would gradually shut down all of its nuclear reactors for safety checks starting from Friday, four days after the deadliest nuclear industry accident in Japanese history.
Four workers were killed on Monday when super-hot non-radioactive steam gushed from a ruptured pipe at the company's Mihama nuclear plant, 320 km (200 miles) west of Tokyo.
Japan's second-largest power utility, which has 11 reactors serving the heavily industrialised area around the city of Osaka, said no power shortages would result from the phased closures.
Kansai Electric said procedures would begin on Friday to shut down three units. The reactor where the accident occurred is already closed while two others are shut for regular maintenance.
The government of Fukui prefecture, the region where the plant is located, had asked for inspections to be conducted.
"Normally it would take about six weeks to carry out the checks," Kansai Electric spokesman Yonezo Tsujikura said at a news conference in Tokyo. Kansai Electric said it would restart two oil-fired generators to help make up for lost nuclear production.
The company said the closures could cost it the equivalent of about $90 million, depending on the duration. Other power companies said they had no plans for shut-downs in the wake of the accident, which has heightened public mistrust of Japan's scandal-prone nuclear industry.
Industry Minister Shoichi Nakagawa said the government would do its utmost to ensure a stable supply of electricity.
Resource-poor Japan, which has 52 nuclear reactors, relies on atomic energy for over a third of its electricity needs.
Kansai Electric said on Tuesday the pipe that burst had not been inspected in 28 years and that it had not taken action even after being advised by a sub-contractor that it needed attention.