The U.S. Occupational Safety and Health Administration has issued more than $500,000 in fines for safety violations that resulted in eight deaths and dozens of injuries at two highly publicized construction projects.

The Hard Rock Hotel in New Orleans.

At the Hard Rock Hotel site in New Orleans, where the top floors collapsed in October, OSHA fined 11 companies more than $315,500, the agency said in a bulletin. In the trouble-plagued Interstate 4 expansion project in Orlando, Florida, OSHA fined contractors almost $54,000 for two injuries, one of them fatal, and more than $147,000 for violations that led to other injuries.

In the New Orleans accident, which killed three workers and injured several others, OSHA put much of the blame on Heaslip Engineering, based in Metairie, Louisiana, according to a local news report. The building's upper floors were not properly designed, causing structural problems that led to the collapse.

The company was fined $154,200. An attorney for the firm said OSHA's conclusions are unwarranted.

In Orlando, the massive highway expansion project, underway for five years, has been troubled from the start. Five workers have died in struck-by accidents, and dozens of workers' compensation claims have been filed.

This week, OSHA said the multinational contractor Skanksa, which teamed up with Granite Lane to form SGL Constructors, exposed workers to struck-by hazards and was guilty of willful violations.

Another company, Universal Engineering Services, was fined $12,145, OSHA said.

"These employers failed to take appropriate action and provide the necessary protections to employees while they worked on this highway improvement project," said OSHA Regional Administrator Kurt Petermeyer. "Occupational safety and health standards exist to protect workers' safety."

The companies cited in the Florida and Louisiana accidents have 15 days to comply, request an informal conference with OSHA officials or contest the findings.