Builders of the Shanghai World Financial Center - which will be among the globe's top-three tallest buildings when it's completed next spring - installed a major component yesterday that will prevent the tower's occupants from experiencing motion sickness on windy days.

A steel wind damper is installed on the 90th floor of the Shanghai World Financial Centre to imprive stability of the tower. [Oriental Morning Post]

A giant steel wind damper was hung on the structure's 90th floor to improve stability in Shanghai's blustery skies, the construction firm said yesterday.

The equipment, 400 meters above the ground, is similar to the device used in Taiwan's Taipei 101, currently the world's tallest building.

The Shanghai damper weighs 540 tons and is made up of steel frames that hold huge counterweights.

A computerized sensor connected to the damper automatically swings the counterweights to offset the force of the wind, said officials with Mori Building, the Japanese investor in the financial center development project.

The equipment will function automatically whenever the wind blows at more than 20 meters per second, and most inhabitants will feel no sway at all once the damper is activated, Mori officials said.

The damper is needed because Shanghai is often influenced by typhoon weather, they said. Among the beneficiaries will be the future guests of a five-star hotel planned to run from the 79th to 93rd floors.

The 101-story building will be 492 meters tall when it's finished, compared with 508 meters for Taipei 101. Both are scheduled to be eclipsed by a skyscraper in Dubai, which is planned to soar to a height of 800 meters.

By May 28, the building had reached 400 meters with the completion of its 90th story.

The picture of Shanghai's Pudong district shows the Shanghai World Financial Centre is currently under construction. (file)