Biography

Exley is widely regarded as one of the pioneers of cave diving, writing two major books on the subject: Basic Cave Diving: A Blueprint for Survival and Caverns Measureless to Man published by Cave Books, (ISBN 0-939748-25-8), and establishing many of the basic safety procedures used in cave and overhead diving. Exley was also a pioneer of extreme deep water diving. In the book, Diving into Darkness (a story about Dave Shaw

David Shaw (diver)

David Shaw was an Australian scuba diver, a technical diver and an airline pilot for Cathay Pacific, who flew the A330-300, A340-300 and A340-600...

 and Don Shirley

Don Shirley (diver)

Don Shirley is a world renowned English cave diver and Instructor Trainer and who currently resides in South Africa. He holds the license to International Association of Nitrox and Technical Divers Southern Africa Region. Shirley has been involved in diving since 1974, conducting recreational...

) it was commented: "Exley's status in the sport is almost impossible to overstate."

Exley began diving in 1965 at the age of 16. That very year he entered his first cave and was hooked on cave diving for the remaining 29 years of his life.

He was the first in the world to log over 1,000 cave dives (at the age of 23): in over 29 years of cave diving, he made over 4,000. He is one of the few divers to survive a 122 meter (400 ft) dive on compressed air. During his diving career, he set numerous depth and cave penetration records.

He died aged 45 on April 6, 1994 while attempting to descend to a depth of over 300 metres (1,000 ft) in a cenote

Cenote

A cenote is a deep natural pit, or sinkhole, characteristic of Mexico and Central America, resulting from the collapse of limestone bedrock that exposes groundwater underneath...

 called Zacatón

Zacatón

Zacatón is thermal water filled sinkhole belonging to Zacatón system - group of unusual karst features located in Aldama Municipality in the northeastern state of Tamaulipas, Mexico. It is the deepest known water-filled sinkhole in the world with a total depth of...

 in Mexico. He made the dive as part of a dual dive with Jim Bowden

Jim Bowden (diver)

Jim Bowden is an American SCUBA diver, and an elite technical diver, famous as a cave diver and as a deep diver. In 1994 he set a world record, since broken, by diving to . He is one of only eight people who have dived below a depth of on self contained breathing apparatus...

, but Bowden aborted his descent early when his gas supply ran low. Exley's body was recovered only because he had hooked his arms in the descent line, perhaps to sort out gas issues. His wrist-mounted dive computer read a maximum depth of 268 meters (879 ft). It is not certain what caused his death; team members concluded the causes "...could include stress of HPNS

High pressure nervous syndrome

High-pressure nervous syndrome is a neurological and physiological diving disorder that results when a commercial diver or scuba diver descends below about while breathing a helium–oxygen mixture. The effects depend on the rate of descent and the depth...

 exacerbated by the narcotic

Nitrogen narcosis

Narcosis while diving , is a reversible alteration in consciousness that occurs while scuba diving at depth. The Greek word ναρκωσις is derived from narke, "temporary decline or loss of senses and movement, numbness", a term used by Homer and Hippocrates...

 effects of nitrogen at that depth". The line was also wrapped (deliberately) around Exley's tank valves. Bowden and other experts have theorized that Exley may have done this in anticipation of his own death to prevent any dangerous body recovery operations.

Sheck Exley is one of only eight people in the history of technical SCUBA diving to dive below 800 feet.

Some of Exley's exploits are described in Daniel Lenihan's book Submerged. This book describes how Exley was a very influential dive buddy of the author, who went on to form the National Park Service's Submerged Resources Center

Submerged resources center

The Submerged Resources Center is a unit within the United States National Park Service. The unit is based out of Lakewood, Colorado in the NPS Intermountain Region headquarters.-History:...

.

External links

• Basic Cave Diving: A Blueprint for Survival (description of book and author)
• Under Pressure, Jerry Shine, Wired Magazine 3.1, Nov 1995