SeaWorld Orlando trainers on Monday began wearing new, custom-designed emergency vests as a safety improvement in the wake of Dawn Brancheau's death in 2010.
Starting with Monday's 11:30 a.m. performance of the show "One Ocean," trainers at all of SeaWorld's theme parks who work in close proximity of killer whales donned the vests, which become buoyant with the pull of a cord.
The emergency vest also has a small scuba tank and regulator, which provides a few minutes of air, SeaWorld trainers said. The vests, described as lightweight, can also break-away so trainers can ditch them, if necessary.
"It's an opportunity for us to increase the safety of what we consider an already safe environment and make it even safer," said Kelly Flaherty Clark, animal training curator.
SeaWorld said it worked on creating the vest for more than three years, testing different prototypes in trying to find the best technology.
The park said the vest is just one aspect of many safety improvements made after a killer whale pulled Brancheau underwater, killing her. Other safety changes include a quick-rising floor in one of the park's pools, automatic gates between the pools and distance protocols -- 18 inches away from whales while standing, 3 feet while kneeling and approaching a whale from its side on the "slideout" ledge.
Would the vests have spared Brancheau's life had they been developed back then?
"I have no idea," replied Clark. "And anything I'd say right now would be pure speculation."
David Kirby, author of "Death at SeaWorld" book, said the vest "would not have saved any of the trainers who were killed by orcas. Dawn was rammed and dismembered by Tilikum. A vest and spare air would have been useless."
Kirby also commented about the dangers of using compressed air.
"If a trainer is pinned to the bottom, breathing air, and the whale decides to rush them to the surface, they might suffer from the bends if they don't exhale properly," Kirby said.
SeaWorld shows will not change as a result of trainers wearing the new vests, park officials said.
The vests are not related to mandates issued by the Occupational Safety and Health Administration.
Earlier this month, the U.S. Court of Appeals in Washington, D.C. upheld OSHA safety citations issued to SeaWorld following Brancheau's death. The marine park has still not decided whether it will appeal the ruling to the U.S. Supreme Court.
Watch Local 6 News and stay with ClickOrlando.com for more on this story.