Diving at an underwater shipwreck site may seem an unlikely family vacation adventure.
But a popular, new activity called Snuba has made it possible for children, their parents and their grandparents to dive as deep as 20 feet in the Atlantic Ocean -- without air tanks -- and swim with the kaleidoscope of tropical fish, barracuda, moray eels and nurse sharks that gather around sunken vessels in the Florida Keys.
In the Pacific, novices of all ages are gearing up for a shallow-water diving experience that gives them a feel for what it's like to scuba dive as they explore the coral reefs around the volcanic islands of Hawaii.
"Snuba is diving for the masses," says Michael Arnell, president of Snuba International, the California firm that manufactures and leases Snuba equipment, trains Snuba guides, administers insurance and promotes the sport. "It's easy and it's user friendly. It's the Disneyland approach to diving."
Snuba -- or Surface Nexus Underwater Breathing Apparatus -- takes snorkelers down to the fish and the coral where once only certified scuba divers could go. It was designed in 1988 for tourists who want to go beyond snorkeling without committing the time and money required for scuba, Mr. Arnell says.
There are no heavy air tanks to carry; divers need only wear a mask, flippers, weight belt and Snuba mouthpiece, or regulator. The regulator is attached to a 20-foot hose that extends to the surface, where air tanks float in a raft during the dive.
At least 30 hours of training must be completed for scuba certification, but Snuba instruction is limited to a brief orientation session in a swimming pool or on board a tour boat.
After no more than an hour and sometimes as little as 15 minutes of training, the whole family -- including children as young as 8 -- may venture with a trained Snuba guide into an undersea world that otherwise would be beyond their reach.
The toughest challenge of Snuba is overcoming logic and feelings of claustrophobia, which argue against trying to breathe underwater and urge the diver to escape to the surface. For most divers, these feelings pass quickly and it becomes easy to ignore the gurgling of air bubbles from the regulator to the surface and concentrate on the beauty of the sea life below.
Some scuba divers laugh at Snuba and its "dog on a leash" approach to diving. Others express concern that the training is insufficient to properly prepare Snuba divers for emergencies. A rapid, panicky ascent could result in serious injury or death.
"We have a perfect safety record," Mr. Arnell says. "Since 1988, 700,000 people have tried Snuba, and we've had no insurance claims. Our liability insurance goes down every year."
Jeff Tamlyn, who owns the rights for Snuba in the Florida Keys, conducts a $30 one-hour Snuba lesson in a hotel swimming pool before taking his students out on a scuba boat for a $70 afternoon adventure.
"We go through all the skills they need to know in the pool," he says. That includes normal breathing, slow ascents and descents and techniques to relieve pressure in the ears and drain water from the mask. It's important never to hold your breath, he says, and students also learn what to do if a mask should come off or the regulator pops out.
"It's more fun for the person and it makes them feel at ease if they learn how to handle it in the pool," he says. "My job is keeping it safe and making sure my customers have the most fun possible."
Feelings of panic are an expected reaction during the first seconds and minutes of underwater breathing through the regulator, Mr. Tamlyn says. An acceptance of the wonders of breathing underwater follows, and then a more casual attitude and a desire to go deeper in search of fish.
"I never force anybody to do anything they don't want to do," he says. "We go to whatever depth they're comfortable with. There are people who will make their first dive on the surface because they don't feel ready to go deeper."
Only pregnancy, a bad cold or poor health should discourage interested vacationers from giving this warm water sport a try, says the 35-year-old Snuba guide, who offers year-round tours in Key Largo and will expand to Key West in 1995.
"Snuba is a really unique way to experience diving for the first time," Mr. Tamlyn says. "You don't have to be a strong swimmer, and it's a great way to explore the reef the way it should be seen."
The reef system is three to seven miles offshore with more than 200 varieties of coral, he says. He takes some groups to shipwrecks, which are "great habitats" for colorful parrot fish, wrasses and angelfish that attract larger feeding fish.
"Hundreds of thousands of people visit these reefs each year," says Mr. Tamlyn, who has escorted 1,500 Snuba divers since he opened his business three years ago. "This is one of the most popular diving-snorkeling destinations in the world."
Snuba is strictly a vacation adventure to be enjoyed under the watchful eye of a trained Snuba guide. The equipment cannot be bought or rented. Diving must be done at a site equipped for the sport, and there are only a handful of these around the world.
In the United States, Snuba is available in Florida and four of the Hawaiian Islands. Off the coast of the Big Island of Hawaii, Snuba guide Lynn Ekstrom joins snorkelers on board the Fair Wind trimaran and offers them the opportunity to learn to Snuba in the pristine underwater state park at Kealakekua Bay.
There are Snuba sites at St. John in the U.S. Virgin Islands, in Israel, Japan and the Philippines, with plans for possible expansion to Australia and Belize in 1995.
IF YOU GO . . .
Snuba International, Placerville, Calif. (916) 621- 2024
Snuba Tours of Key Largo and Key West, Fla. (305) 451- 6391
Snuba Tours of Kona, Big Island, Hawaii. (808) 326- 7446