During peak hours, large crowds at theme parks increase the probability of accidents, injuries and in some cases, deaths, industry experts said.
Throw in unpredictable Florida weather, especially here in lightning-prone Tampa, and anything can happen.
Those are the factors to consider in the case of Justin Savers Inversso, an Adventure Island lifeguard who died last week when he was struck by lighting, according to William Avery, a consultant on theme park safety.
"You can do everything by the book, you can have the best plan in the world and still get caught," said Avery, whose firm is based in Maitland. "You can bank on lightning being predictably unpredictable."
Inversso was evacuating patrons from the 700-foot tall Key West Rapids ride about 11:50 a.m. on Saturday as a storm was about to sweep through the area, according to relatives.
When lightning struck the tower, Inversso was standing in about two or three feet of water, probably at a curve in the water slide where tube riders sometimes get stuck, relatives said.
The Pasco County High School graduate was taken to University Community Hospital where he died. He just turned 21 the day before. His funeral was held Wednesday in his hometown of Dade City.
Inversso's death is being investigated by the Tampa office of the Occupational Health & Safety Administration. Les Grove, the agency's area director, declined to comment because of the ongoing investigation.
Jim Dean, the president of Busch Gardens and Adventure Island, said in a statement that the fatal lightning strike was the first incident of its kind since the water park opened in 1980.
The park has systems, including weather radar, that monitors the approach of severe weather, said Jill Revelle, Busch Gardens spokeswoman. A park manager is responsible for checking on weather conditions, she said.
All of the park's rides are closed and cleared of patrons if lightning is detected in the area, Dean said.
He, Revelle and other park officials declined to comment on Inversso's death and the investigation.
Avery, the safety consultant, said from what he's read in news reports, it appears that Inversso and park officials were following procedure.
But there could have been other factors in play that OSHA investigators could focus on.
"Did he move quickly enough? Was it a particularly busy day?" Avery said. "Did he do what needed to be done to evacuate?"
When he was the safety manager at Polk County's now defunct Boardwalk and Baseball theme park in the 1990s, Avery said the time needed to evacuate patrons depended on how fast a storm was moving.
The industry doesn't have a set time frame for that and it is up to the discretion of park officials, he said.
"But you can't wait until a storm is five miles out," Avery said. "Seconds can be your enemy. In Florida, storms can happen in a short period of time."
Aleatha Ezra, spokeswoman for the World Waterpark Association, said most parks across the nation have a weather monitoring system, but there are no regulations that require them to have one.
There are more than 1,000 water parks across North America, according to the association, which had 79 million visitors last year. Adventure Island had 626,000 in 2010, which placed it eighth on a list of 20 parks with the highest attendance, an industry report said.
Typhoon Lagoon at Walt Disney World tops the list with 2 million visitors last year.
Even with those attendance numbers, reports of lightning striking visitors or park workers is rare, Ezra said.
"Statistically, it's rare, but it's always a possibility," he said. Park operators try to establish solid safety plans, but in Florida, "your park would be shut down half the day if you worried too much," Avery said.
Patrons have a responsibility for their safety too, he said.
"If you see dark clouds, it's a clue. If you see lightning, get out of the water," Avery said. "You shouldn't wait for the park to tell you that."