Tokyo: Tokyo Electric Power Company (TEPCO), the operator of the crippled Fukushima Daiichi nuclear power plant on Saturday said it has built a framework of giant covering for the Number 1 reactor to prevent radioactive materials from spreading and stop rainwater from entering the reactor building.

The company said it plans to complete the covering, a tent-like structure made of steel frames and air-tight polyester sheets, by the end of October.

When completed, the covering will be between 42 and 47meters long and about 54 meters high.

The building housing the Number 1 reactor and those housing the Number 3 and 4 reactors at the plant were badly damaged due to explosions after tsunami caused by a magnitude 9.0 earthquake struck the plant on March 11 this year.

Once the installation is completed at the reactor, TEPCO will consider installing similar coverings for the Number 3 and 4 reactors, the operator said.