The San Francisco-Oakland Bay Bridge reopened Monday, six days after two steel rods and a steel crossbeam plummeted from the span and caused a traffic nightmare for hundreds of thousands of commuters. Crews have worked around the clock since Tuesday night's mishap. Final inspections were completed Monday morning, said Bart Ney, a spokesman for the California Department of Transportation. Vibrations in the rods, affected by strong winds, caused the break, officials said. "We are very happy to return the bridge to public service and go home to see our families," Ney said at a news conference. Engineers finished their sixth night of repair work Sunday. Crews performed stress tests Saturday night, but the results showed the potential for metal grinding, which could cause another break. After stress tests proved successful, engineers did a vibration test by driving trucks on the bridge's lower deck to simulate the effect of vibration. Ney thanked commuters for their patience Monday. "We all know it's been difficult," he said. Officials did not yet know how much repairs to the bridge cost, Ney said.