Diving Deep into Danger

The first dive to a depth of 1,000 feet was made in 1962 by Hannes Keller, an ebullient 28-year-old Swiss mathematician who wore half-rimmed glasses and drank a bottle of Coca-Cola each morning for breakfast. With that dive, Keller broke a record he had set himself one year earlier, when he briefly descended to 728 feet. How he performed these dives without killing himself was a closely guarded secret. At the time, it was widely believed that no human being could safely dive to depths beyond 300 feet. That was because, beginning at a depth of 100 feet, a diver breathing fresh air starts to lose his mind.

This condition, nitrogen narcosis, is also known as the Martini Effect, because the diver feels as if he has drunk a martini on an empty stomach -- the calculation is one martini for every additional 50 feet of depth. But an even greater danger to the diver is the bends, a manifestation of decompression sickness that occurs when nitrogen gas saturates the blood and tissues. The problem is not in the descent, but the ascent. As the diver returns to the surface, the nitrogen bubbles increase in size, lodging in the joints, arteries, organs, and sometimes the brain or spine, where they can cause pain and potentially death. The deeper a diver descends, the more slowly he must ascend in order to avoid the bends.

In 1956, a Royal Navy boatswain had successfully dived to 600 feet, breathing a mixture of helium and oxygen to avoid nitrogen narcosis, but he took 12 hours to resurface. Keller, by comparison, returned to the surface after his first record dive in less than an hour. He boasted of using "secret" mixtures of gases for his underwater breathing apparatus, with different mixtures designed for different depths, but he wouldn't disclose exact figures. After an editor from Life, who had accompanied Keller on his 728-foot dive, wrote an article about their accomplishment, the U.S. Navy took interest. So did the Shell Oil Company. . . . . . . .

For the rest of this great, in-depth story on commercial diving, written by Nathaniel Rich for the New York Times Book Review, go to www.nybooks.com/articles/archives/2013/feb/07/diving-deep-danger/?pagination=false