SAN FRANCISCO (KCBS)— Cal-OSHA is investigating Monday’s fire at the former Renoir Hotel in San Francisco that injured eight construction workers from smoke inhalation.

Two companies were involved in renovation work at the site when the three-alarm blaze broke out. The general contractor is San Francisco-based Pacific Structures. The sub-contractor is Oakland-based Emerald Steel.

Cal-OSHA spokeswoman Kathleen Hennessy said investigators will spend the next six months reviewing records and safety protocol put in place. She said over the last five years, there have been no safety violations involving Emerald Steel and just one involving Pacific Structures.

“These were violations of regulatory or general nature. They weren’t serious or willful, which are a category of safety violations that could result in serious harm to workers,” Hennessy said.