7th diver's death raises concerns on Cape Ann

So when he asked five friends to spend a day diving to the sunken ship Chester Poling, just outside Gloucester Harbor, they readily agreed. For Blanchette, 49, a Dracut resident who had been scuba diving for 37 years, the 90-foot dive would serve as a tuneup for more rigorous deep-sea dives planned in North Carolina, Long Island, and New Jersey.

But an hour after he slipped into the cold waters off the coast of Gloucester on May 18, fellow crew members began to worry. Thirty minutes later, David Cunningham dived into the water with other divers and searched the bottom for their colleague. A day later, Blanchette’s body was found just yards from the wreck.

He became the seventh scuba diver who has died in waters off Gloucester and Rockport since 2002. The lure of easy access to beaches and the chance to swim among exotic fish while grabbing a lobster or two for dinner have made Cape Ann the most popular diving site in New England.

But Blanchette’s death has many in the New England diving community wondering how such an experienced diver lost his life during a routine excursion. They are eager to hear the official cause of death from state officials investigating.

“A guy like Paul doesn’t just have an accident like that,’’ said John Ferrier, Blanchette’s best friend, who talked to him the night before the fateful dive. “If he thought there was a problem, he would never push the limits. That’s what’s got us all stumped.’’

Ralph Kindred of Franklin dived to the Andrea Doria 25 times with Blanchette and is also baffled about his death. Blanchette used a special rebreather machine, which uses oxygen and recycles exhaled gas to allow divers to stay below for several hours at a time.

“There are a lot of people who are curious what took place,’’ Kindred said. “People want to know for their own peace of mind what happened, so they can prevent it from happening to them.’’

Steve O’Connell - a spokesman for the Essex district attorney’s office, which is investigating Blanchette’s death - said that four Cape Ann diving accidents since 2002 were caused by cardiac-related issues and that the other two were listed as accidental drowning.

Diving certification is earned by attending classes at private dive clubs and organizations; there is no government oversight. Most divers are certified for recreational diving, allowing them to dive as deep as 60 feet. Others, like Blanchette, become certified for much deeper diving, sometimes hundreds of feet below the surface.

According to the Divers Alert Network, a North Carolina nonprofit that provides emergency medical advice and tracks diving injuries and deaths, there are between 1 million and 2 million active certified divers in the United States. Each year, the group reports, about 84 divers die in the United States and Canada.

Dr. Petar J. Denoble, the group’s research director, says the most common causes of death are drowning, cardiac-related issues, and arterial gas embolisms, which occur when gas bubbles lodge in arteries that supply blood to the brain.

Although most divers say the sport is as safe as skiing or bicycling, they acknowledge that a combination of factors - from getting tangled in an abandoned fishing net to becoming exhausted from swimming in rough currents - can lead to tragedy.

“It’s inherently dangerous; if you don’t take the proper training, death is imminent,’’ said Todd Randall, president of the North Shore Frogmen’s Club, based in Beverly.

During an underwater expedition last year to a sunken German U-boat off Block Island, Randall was supposed to spend just 30 minutes on the ocean floor, but spent an extra half-hour inspecting the wreck. In order to resurface safely, divers must make decompression stops to eliminate gases like nitrogen from their blood. On that day Randall’s wrist computer broke, and he misjudged his stops, leading to joint pain and a case of the bends.

“They had to call a helicopter, and they brought me to a hyperbaric chamber, and I spent eight hours in there. I had symptoms for a good month after that,’’ Randall said.

Divers say age is another factor contributing to deaths at sea.

“You got an aging population of divers,’’ said Ferrier, 58, of Saugus. “There’s a bunch of us that are out there and over 55, and we worry about our health and try and stay in shape, but you never know.’’

Vicky VanDerwerken of Rockport wonders if her husband, Steve, might still be alive if he did not go scuba diving Aug. 16, 2005. “Steve didn’t drown; he had a heart attack,’’ she said.

While Blanchette’s friends wait to learn the cause of his death, few say the accident will prevent them from returning to the water. Cunningham hopes to honor his friend and mentor by placing a plaque on the bottom of the ship where Blanchette was found.

Ferrier went diving on a recent Sunday and said he thought of his friend while underwater.

“Paul wouldn’t want anybody to stay out of the water,’’ Ferrier said. “He’d say it’s a great day to dive.’’

Steven Rosenberg can be reached at srosenberg@globe.com.