Japan’s Tokyo Electric Power Co. (TEPCO) indicated that the radiation levels of the primary Fukushima power station is enough to kill a human being in an hour.

Through a thorough survey of the plant, TEPCO found the radiation levels of the Number 1 reactor as of late ranged between 7.0 and 9.7 sieverts (enough to poison a healthy human being) per hour after surveying six locations within the primary containment vessel, reports the Japan Times.

In the first attempt to monitor the levels of radiation, TEPCO sent a robot into the vessel on Friday, expecting it to stay alive for ten hours--it was only functional for three hours and only completed two-thirds of the tasks given.

TEPCO then tested eight of it’s employees, along with thirty-six workers hired by contractors, who worked within the facility. The company found that the total dosage was 1.73 millisieverts, which is enough to cause radiation burns.

TEPCO spokesman Teruaki Kobayashi insisted that the survey found no major issues around the opening leading to the underground part of the vessel, meaning for future surveys it will be much easier to remove any nuclear deposits from under the vessel.

The Number 1 reactors was one of the three damaged by the 9.0 magnitude Tohoku earthquake of 2011 that devastated the region.