By Nicholas Nehamas

The contractors who designed and built the disastrous Florida International University bridge have been cited by federal authorities for several "serious" worker-safety violations and face tens of thousands of dollars in fines.

The companies failed to provide workers with a proper safety line and did not remove them from the area despite the bridge developing cracks of "significant width, depth and length at critical locations," according to a series of citations issued Tuesday by the Occupational Safety and Health Administration (OSHA).

The FIU pedestrian bridge collapsed March 15 while it was still under construction over Southwest Eighth Street, killing five motorists below and a worker, Navaro Brown, who had been standing atop the span. An additional five workers were seriously injured, including one, Kevin Hanson, who sustained a serious brain injury and went into a lengthy coma.

Footage of the accident captured the awful moment when the bridge fell. One worker, clearly visible, is seen in mid-air tumbling toward the ground.

On Tuesday, OSHA cited five companies for seven worker-safety violations, fining them a total of $86,658 in proposed penalties. The companies are designer FIGG Bridge Engineers; builder Munilla Construction Management; Bolton Perez & Associates, which provided engineering and inspection services; Structural Technologies, which specializes in post-tensioning work on bridges; and a concrete contractor, the Structural Group of South Florida. (That last company, based in Homestead, doesn't appear to be connected in corporate records to Structural Technologies, a national firm.)

"Collectively, these employers failed to take appropriate action and provide the necessary protections to their employees while they were working on the bridge on the day it collapsed," OSHA regional administrator Kurt A. Petermeyer said in a statement.

OSHA, which is part of the U.S. Department of Labor, described the citations as "serious" violations.

They mark the first punishments handed down for the deadly accident, although more may follow. The National Transportation Safety Board is investigating the cause of the collapse, a process that likely will take months. Ultimately, a criminal case remains possible, depending on the NTSB's findings, although Florida law may shield the companies from being charged, legal experts say. Several civil lawsuits are ongoing.

The companies have 15 business days to accept the citations, schedule a conference with OSHA or contest the findings, according to the agency.

Michael Hernández, a spokesman for MCM, provided the following statement: "MCM views OSHA's action as a positive first step toward understanding the root cause of this tragic accident. While MCM is still reviewing the OSHA fall protection citation, it is noteworthy that OSHA has not claimed that the cited conditions had anything to do with the FIU bridge span's failure."

The other contractors did not respond to requests for comment. Neither did FIU.

FIGG and Bolton Perez were each cited for not evacuating their workers from the bridge, which had begun to develop cracks even before it was swung into place across the busy road on March 10. OSHA said the cracks "compromised the structural integrity of the bridge," although a FIGG engineer left a voice mail for the Florida Department of Transportation saying the cracks were not a safety threat days before the collapse. The agency said employees should have been removed from the "zone of danger" until the bridge was temporarily shored up at the north end where the cracks appeared.

In addition, OSHA cited the Structural Group of South Florida because employees were using a safety line "that was not tensioned and was laying on the deck of the bridge canopy," instead of being placed above the workers. MCM and Structural Technologies were also cited for that violation, as well as for attaching five employees to a single, improperly installed line, exposing them to dangerous falls.

When the bridge collapsed at 1:47 p.m., the workers came crashing down, too.

Brown, a 37-year-old from Jamaica, worked for Structural Technologies. He died at a local hospital after being rescued from the rubble by first responders. Hanson also worked for Structural Technologies. His family took to the Internet to raise nearly $20,000 after he went into a coma. He has since regained consciousness.

Brown and the other workers were on top of the bridge to tighten, or re-tension, rods running through the span that strengthened the structure. Who gave the order to send them up there -- and who decided to keep the road open while construction work was being performed -- remain unclear. It's possible the work was being performed to tighten the alarming cracks that had been opening in the bridge.

A meeting was held the morning of the collapse to discuss the cracks but FDOT refused to release minutes from the meeting, citing NTSB instructions. The Miami Herald is suing the department to compel their release.

The bridge's design suffered from a calculation error that may have weakened it at a key connection point where the cracks developed, according to independent engineering experts consulted by the Herald. That weakness may have led to the collapse, the engineers said.

Miami Herald staff writers Andres Viglucci and Jenny Staletovich contributed to this report.

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