(ABC News) -- Geoff Fahringer is an expert diver. For a dozen years, he's been on the dive rescue team for the Collier County Sheriff's department in Naples, Fla. But there's one thing he'd never done - until now. On a sunny day in Naples this month, Fahringer got into a car on a boat ramp and steered right into an 8-foot-deep canal.
"What we're going to show is that you have a minute or less to get the window open on your vehicle, and get out of the car. Get the window down, get out of the car," he said.
It's a terrifying thought, your car suddenly plunging into deep water, or being swept away in a flood.
Every year, as many as 400 people drown in vehicles, according to data collected by Canadian researcher Gordon Giesbrecht. A professor of thermophysiology at the University of Manitoba, Giesbrecht has spent the last eight years sinking cars with people in them to determine the best way for drivers and passengers to escape.
The bottom line says Giesbrecht, is you cannot wait for rescuers to get to you. There simply isn't enough time.
"We're telling people that you have to get out of the vehicle before the water gets up against the windows, and that's really in the first 30 to 60 seconds."
That means, don't reach for your cell phone when you hit the water. "Don't call 9-1-1 from inside a sinking vehicle," he said.
Giesbrecht brought his insights to Naples for a demonstration sponsored by the county's Safe and Healthy Kids Coalition. The tests are designed to show it is possible for drivers and passengers to scramble out of a sinking vehicle in time, if they know just what to do.
Florida, with its many canals, has the highest vehicle drowning rate in the nation. Just two months ago in Collier County a young mother and her two daughters, ages 3 and 4, drowned when their car careened into a canal after rear ending another vehicle. By the time rescuers got to 33-year old Cecilia Renee Douglas, and daughters Madison and Rylee, they had been underwater for half an hour.
"You are responsible to save yourself in that scenario," said Giesbrecht, "you are not going to wait for help."
After 100 tests, with the help of his PhD student Gerren McDonald, Giesbrecht has developed a simple but crucial protocol for escaping before it's too late: seatbelt, window, children, out. Unbuckle your seatbelt, get a window down (the rear passenger windows are ideal if they open because the heavy front of a car will tilt into the water first so the back seat stays dryer longer), unbuckle any children (start with the oldest first so they can escape while you're unbuckled any infants), and get out through the open window.
ABC News watched a series of demonstrations of these techniques. In the first one, Geoff Fahringer was by himself in a 1987 Oldsmobile. The vehicle rolled down the boat ramp and into the chilly water of a canal. Those on shore held their breath as the car starting sinking with Fahringer inside. He followed the protocol though, and got out in less than 30 seconds.
He admits, even though he was prepared, his heart was racing, "It was very intimidating," said Fahringer, "the car went down quicker than I thought it would."
The series of tests included packing the car with a driver and three passengers, another one included two adults, with three child-dummies seated in back. In every instance, as the car filled with water, those inside were able to scramble out in time.
The key says Giesbrecht is to understand what you have to do, long before one of these terrifying accidents ever happens.
"When we're scared is not the time to be figuring things out," he says, "That's why we're trying to get this message into the psyche of the public."
Clearly this escape procedure won't work in all cases. Just this month six Ohio teens died after the car they were riding in flipped off the road and landed upside down in a pond. Two teens did escape, but only because they were able to get out a window that had busted open. Giesbrecht's procedures are designed for cars floating upright.
Many people mistakenly believe that they should let their vehicle sink and fill with water to equalize the pressure, so they can then open the doors and escape.
"The problem is people don't realize that in many of these vehicles the truck, even though it is a separate compartment, it is still part of the passenger compartment, and you need to wait for all of the air to clear out of the trunk before it equalizes," he said. By then it may be too late.
"There's this fallacy that you have this magic air bubble," said Fahringer. "And if you wait for this magic air bubble you can get a breath and open the doors [but] by then it's too late."
In all of the testing that's been done, the vehicles have been equipped with windows that roll down, so the car can be repeatedly dunked. Most cars on the road these days have electric power windows and there is no requirement that the windows continue to operate in water. Auto manufactures say the windows should work briefly when you hit the water, but there's no guarantee.
So Giesbrecht has a back-up plan. He carries a simple window-breaking device in his vehicle. The tool, a spring-loaded center punch, is pressed into a corner of the window. One or two simple pushes and the window shatters. This reporter tried it with the $10 "resqme" brand and the window was in pieces in just seconds. Giesbrecht recommends the devices be easily accessible and in the open, perhaps hanging from the rear view mirror.
All this testing is leading to a major safety change. Beginning next month, 9-1-1 operators will start learning a new protocol to follow when they receive frantic calls from those trapped in sinking vehicles. "It shifts the focus from finding out where the vehicle is and telling people to be calm," Giesbrecht said, "to saying, okay do what I tell you."
Operators will be instructed to send a clear message. get that seatbelt off, get that window down. Get out. Giesbrecht is convinced, "It absolutely will save lives."