A former worker at Japan's crippled Fukushima nuclear plant has filed a lawsuit alleging the plant's operator, TEPCO, sent crews into highly radioactive areas without proper protection.
Thousands of workers were involved in getting the damaged plant and its reactors under control after it was hit by the powerful 2011 tsunami.
The former worker, identified only as Shinichi, has filed a legal complaint with Japan's labour office, seeking an improvement of safety standards.
"From the outset there was no mention about water nor any instructions as such," Mr Shinichi said.
"We were not given any information. All we were told was to do our work, to connect the switchboards."
Mr Shinichi says TEPCO knew the risks posed by highly radioactive water that was pooling in the reactor buildings.
He claims the company sent crews into the flooded areas despite this knowledge.
"When I went inside I saw a pool of water. If you're a nuclear plant worker you know that water on the floor is bad news, you just don't touch it," he said.
TEPCO spokesman, Yoshimi Hitosugi, says the company was unsure if there would be highly radioactive water at the time.