A prototype tsunami lifeboat built by shipbuilder IHI Corp. under a government project has undergone major safety tests, proving it can withstand shocks from tidal waves and right itself, the transport ministry's Shikoku regional offices said Monday.

The boat, which some have called a contemporary Noah's Ark, is 8.4 meters long and weighs 3.5 tons, with room for up to 35 people and water and food supplied. The boat also has toilet facilities and can stay afloat for around one week.

The boat is designed to serve as a closed shelter to accommodate the elderly and toddlers who cannot escape quickly in the event of a disaster.

Last month, the prototype unit was dropped to the ground from a height of 5 meters to simulate the envisioned impact it may sustain hitting a structure while drifting at 10 meters per second.