The accident occurred at 6:45 a.m. Monday in Santa Clara and the worker was an employee of Gerdau Ameristeel, a subcontractor on Levi Stadium, California Division of Occupational Safety and Health spokesman Peter Melton said. Cal-OSHA did not immediately have additional details about the accident and did not identify the worker.
In a statement, the 49ers said their "sincerest thoughts and prayers are with the family, friends and co-workers affected by this tragedy."
The stadium is scheduled to be finished by July 2014. An elevator mechanic, 63-year-old Donald White, was killed at the construction site in June when he was struck by a counterweight while working in a shaft.
White had worked as an elevator mechanic for more than 40 years and was employed by Schindler Elevator Corp., a subcontractor for the stadium's general contractor, Turner-Devcon.
The $1.2 billion stadium project is expected to open its doors just in time to host Super Bowl 50 in the heart of the Silicon Valley.
The airy, open stadium would have the largest lower bowl in the league, ensuring the 68,500 fans are close to the action.
The construction costs are being paid by $800 million in seat and luxury box sales, along with a 20-year, $220 million naming rights agreement with Levi Strauss and Co. announced in May.
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