Masao Yoshida

Who was Masao Yoshida?

Masao Yoshida was born in Osaka, Japan and was a General Manager in the Nuclear Asset Management Department of the Tokyo Electric Power Co., Inc., Japan. He was the plant manager during the Fukushima Daiichi nuclear disaster, where he played a critical role by disobeying corporate headquarters orders to stop using seawater to cool the reactors. According to nuclear physicist, Dr. Michio Kaku, the decision to use seawater arguably prevented a much greater disaster. The massive influx of seawater is the only thing that stopped the cores from exploding, according to Dr. Kaku, who added this was a last-ditch effort. Yoshida managed to gain the trust of Prime Minister Naoto Kan, whom he met the day after the tsunami on a plant tour. They had both attended Tokyo Institute of Technology.

On 12 March 2011, about 28 hours after the tsunami struck, Yoshida and other TEPCO executives had ordered workers to start injecting seawater into Reactor No. 1 to keep the reactor from overheating and going into meltdown. But 21 minutes later, they ordered Yoshida to suspend the operation. Yoshida chose to ignore the order and ordered the plant workers to continue.