Updated

Everything is big with New York's Empire State Building, so upgrading the 20th century elevators running up and down its 102 floors without disrupting thousands of office workers, visitors and tourists each day is no small task.

The office and retail tower and Otis Elevator Co., the nation's best-known elevator manufacturer, announced Thursday a partnership to replace and modernize the building's elevators to bring them into the computer age and reduce passenger wait time. It's the final phase of a $550 million renovation project.

For the Empire State Building -- among the world's most photographed buildings, reproduced into countless paperweights and star of a 1933 movie with King Kong hanging from its side -- the renovation caps its 80th year.

And for Otis, which sold its first elevators in 1853 but now gets much of its business in China's booming office construction market, working at the marquee office tower in midtown New York is as high profile as it gets.

"When you're young from another country you think of the Empire State Building," said Didier Michaud-Daniel, Otis' president who hails from France. "The Empire State Building is known worldwide, so in terms of image it's a great opportunity for us to talk about what we're going to do there."

The newly refurbished elevators promise quick and efficient rides to make the prized address even more attractive to tenants, who also are benefiting from upgraded lighting, heating and cooling and other systems.

Anthony Malkin of the Empire State Building Co., which owns the tower, said his company has been leasing to tenants that occupy entire floors or multiple floors and expect premier appearances and service.

"We're touching on everything, restoring the Art Deco lobby to its original grandeur and a new energy-efficient system," he said.

Upgrading all 68 elevators and replacing 13-ton machines with new equipment while workers, tourists and others enter and leave will be a major effort. The elevators will carry nearly 10 million people each year, Otis said.

Malkin called it the largest elevator modernization of its kind in the world and Otis, a United Technologies Corp. subsidiary based in Farmington, Conn., says it's the biggest in its 158-year history.

The two sides did not disclose how much the contract, which includes a 10-year maintenance agreement, is worth.

Michael Poon, director of technical support at Motion Control Engineering Inc., an elevator control manufacturer in Rancho Cordova, Calif., said elevator upgrades are common, but the Otis-Empire State Building project is unusual for its size and complexity.

With lifespans of 15 to 30 years, elevators require frequent upgrades to replace aging, inefficient equipment, he said.

"It's almost like upgrading your kitchen in your house," he said. "The equipment is getting too old and too costly to maintain."

In addition, elevators have joined nearly all other equipment in the move from mechanical to digital, requiring improvements almost as frequent as computer upgrades, Poon said. Computers can efficiently direct elevators to where passengers are, shut elevators down to save energy and communicate with elevator operators who are becoming networking experts, he said.

The Empire State Building's design specifications and bidding process lasted more than a year in what Malkin called a "hotly competitive process." Only three elevator manufacturers -- Schindler, ThyssenKrupp and Otis -- could credibly compete, he said. Otis came up with a novel and innovative staffing system, Malkin said.

The project is a homecoming for Otis, which designed and installed the Empire State Building's original elevators during the Depression. It will hire a full-time branch manager to run the project that is set to begin in November and be finished in March 2014. It will involve as many as 60 workers on two shifts a day, six days a week.

The number of tenants has declined to fewer than 200 from 561 since 2006 as tenants rent entire floors or multiple floors and the building's management seeks larger and higher quality tenants, Malkin said. The renovations, including the new elevators, are part of the plan.

The new elevators promise to route passengers better and reduce their wait times, Otis said. Michaud-Daniel said it's probably the first time ever in a building this size that elevator equipment will be as good or better than those newly installed.

"I've been working in the industry 30 years and for me, coming from France, it was a dream getting the Empire State Building back," he said. "We're extremely proud of it."