A federal appeals court in Washington on Friday upheld an agency’s findings that SeaWorld violated federal law by exposing killer whale trainers to hazardous working conditions.

The case involved the 2010 death of SeaWorld of Florida LLC trainer Dawn Brancheau, who was killed when Tilikum, a killer whale, pulled her into the water during a performance. Labor officials issued three citations to SeaWorld, and the company challenged one that found a “willful” violation of federal law requiring employers to protect against “recognized hazards” in the workplace that could cause “death or serious physical harm.”