Workers re-entered Japan's damaged Fukoshima nuclear plant Thursday for the first time since a powerful earthquake and tsunami struck on March 11, triggering an explosion at the facility.
The move is an essential step towards setting up the cooling system that officials hope will eventually help bring the plant into a state of cold shutdown.
Workers were given the go-ahead to enter Unit 1 on Thursday after samples taken by a robot last Friday showed radiation levels in some areas were low enough that humans could safely enter.
The workers on Thursday were connecting ventilation equipment in Unit 1 in hopes of absorbing some of the radiation from the air inside the building, Kyodo News reported.
Nuclear workers installed eight pipes that connected to a ventilation turbine at a building near to the No. 1 reactor.
The goal is to clean the air within the building by pumping it through a filter designed to capture radioactive contamination.
Once the system is working, it's hoped that radiation levels will be lowered to the point it is safe for workers to be inside the reactor building while they set up the cooling system.
The work is likely to take four or five days, said the Tokyo Electric Power Co., which operates the plant.
Taisuke Tomikawa, a spokesman for TEPCO, said the two workers that entered the building Thursday were inside for only about 25 minutes and were exposed to about 2 millisieverts of radiation.
In order to minimize any potential damage, the workers wore masks and breathed bottled air, The Associated Press reports.
The two workers are part of a team of about a dozen who are expected to rotate into the building for short shifts, to limit the risk of exposure.
The Tokyo Electric Power Company, which runs the nuclear plant, has released a plan to rein in the on-going crisis within the next six to nine months.
The plan is a two-stage process that will see new systems built to cool down the nuclear fuel, reduce radiation levels and decontaminate the water that has become radioactive.
TEPCO will then achieve a "cold shutdown" of the reactors and temporarily cover the damaged buildings, it said, though it remains unclear when residents may be allowed to return home.
All those who live within a 20-kilometre radius of the plant have been evacuated. There is no word yet on when they will be able to return home.
With files from The Associated Press
