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|Born||7 August 1974|
|Died||17 December 1994 20) (aged|
Deon Dreyer (7 August 1974 – 17 December 1994) was a South African recreational scuba diver who died in Bushman's Hole in South Africa. Cave diver David Shaw died more than 10 years later whilst attempting to retrieve Dreyer's cadaver.
Scuba diving is a mode of underwater diving where the diver uses a self-contained underwater breathing apparatus (scuba), which is completely independent of surface supply, to breathe underwater. Scuba divers carry their own source of breathing gas, usually compressed air, allowing them greater independence and freedom of movement than surface-supplied divers, and longer underwater endurance than breath-hold divers. Although the use of compressed air is common, a new mixture called enriched air (Nitrox) has been gaining popularity due to its benefit of reduced nitrogen intake during repetitive dives. Open circuit scuba systems discharge the breathing gas into the environment as it is exhaled, and consist of one or more diving cylinders containing breathing gas at high pressure which is supplied to the diver through a regulator. They may include additional cylinders for range extension, decompression gas or emergency breathing gas. Closed-circuit or semi-closed circuit rebreather scuba systems allow recycling of exhaled gases. The volume of gas used is reduced compared to that of open circuit, so a smaller cylinder or cylinders may be used for an equivalent dive duration. Rebreathers extend the time spent underwater compared to open circuit for the same gas consumption; they produce fewer bubbles and less noise than open circuit scuba which makes them attractive to covert military divers to avoid detection, scientific divers to avoid disturbing marine animals, and media divers to avoid bubble interference.
Dreyer's father, Theo (who owns a business that sells and services two-way radios) and mother, Marie, raised him in the town of Vereeniging, about 35 miles south of Johannesburg. Dreyer designed "obscenely loud car stereos", had a passion for diving, and loved adventure, (e.g., hunting, racing a souped-up car, and motorcycling).
Vereeniging is a city in Gauteng province, South Africa, situated where the Klip River empties into the northern loop of the Vaal River. It is also one of the constituent parts of the Vaal Triangle region and was formerly situated in the Transvaal province. The name Vereeniging is derived from the Dutch word meaning "association" or "union".
Johannesburg, informally known as Jozi or Jo'burg, is the largest city in South Africa and one of the 50 largest urban areas in the world. It is the provincial capital and largest city of Gauteng, which is the wealthiest province in South Africa. While Johannesburg is not one of South Africa's three capital cities, it is the seat of the Constitutional Court. The city is located in the mineral-rich Witwatersrand range of hills and is the centre of large-scale gold and diamond trade.
Outside Magazine's Tim Zimmerman reports:
Deon had logged about 200 dives when he was invited to join some South Africa Cave Diving Association divers at Bushman's Hole over the 1994 Christmas break. They planned a descent to 492 feet and asked Deon to dive support. He was thrilled. Two weeks before the expedition, Deon's grandfather passed away. Sitting around a barbecue with his family one night, Deon spoke with boyish hubris. "He said if he had a choice of how to go out in life, he'd like to go out diving," recalls his father, Theo, 51.
Dreyer drowned on 17 December 1994, aged 20, during a practice dive while helping a team, assembled by Nuno Gomes, set up conditions for a deep, technical dive scheduled to take place later that week. According to first-hand accounts from those diving with him, Dreyer was lost on ascent around 50 metres (160 ft) from the surface. They conjectured he had probably lost consciousness either because of oxygen toxicity or hypercapnia induced by the high work-rate of breathing at depth.
Nuno Gomes is a scuba diver who lives in New York City. Born in Lisbon, his family relocated to Pretoria when he was 14 years old. He is the holder of two world records in deep diving, the cave diving record from 1996 to the present and the sea water record from 2005 to 2014.
Technical diving is scuba diving that exceeds the agency-specified limits of recreational diving for non-professional purposes. Technical diving may expose the diver to hazards beyond those normally associated with recreational diving, and to greater risk of serious injury or death. The risk may be reduced by appropriate skills, knowledge and experience, and by using suitable equipment and procedures. The skills may be developed through appropriate specialised training and experience. The equipment often involves breathing gases other than air or standard nitrox mixtures, and multiple gas sources.
Oxygen toxicity is a condition resulting from the harmful effects of breathing molecular oxygen at increased partial pressures. Severe cases can result in cell damage and death, with effects most often seen in the central nervous system, lungs, and eyes. Historically, the central nervous system condition was called the Paul Bert effect, and the pulmonary condition the Lorrain Smith effect, after the researchers who pioneered the discoveries and descriptions in the late 19th century. Oxygen toxicity is a concern for underwater divers, those on high concentrations of supplemental oxygen, and those undergoing hyperbaric oxygen therapy.
Two weeks after Dreyer's death, Theo hired a small, remotely operated sub used by the De Beers mining company. It found Dreyer's dive helmet on the cenote floor, but there was no sign of his body.
De Beers Group is an international corporation that specialises in diamond exploration, diamond mining, diamond retail, diamond trading and industrial diamond manufacturing sectors. The company is currently active in open-pit, large-scale alluvial, coastal and deep sea mining. It operates in 35 countries and mining takes place in Botswana, Namibia, South Africa and Canada. From its inception in 1888 until the start of the 21st century, De Beers controlled 80% to 85% of rough diamond distribution and was accused of being a monopoly. Competition has since dismantled the complete monopoly, though the De Beers Group still sells approximately 35% of the world's rough diamond production through its global sightholder and auction sales businesses.
A cenote is a natural pit, or sinkhole, resulting from the collapse of limestone bedrock that exposes groundwater underneath. Especially associated with the Yucatán Peninsula of Mexico, cenotes were sometimes used by the ancient Maya for sacrificial offerings.
Dreyer's parents erected a plaque on a rock wall above the Bushman's Hole entry pool, in memory of their son.In Phillip Finch's book Diving Into Darkness: A True Story of Death and Survival, it was suggested that one of the reasons Dreyer's death created such an impression on the cave diving community was because of the plaque. The bodies of most other divers who die, even whilst cave diving, are recovered. However, for many years it was assumed Dreyer's body would never be recovered from the cave because it was simply too deep, but the plaque was a continual reminder to cave divers that his body lay within.
Ten years later, October 2004, renowned cave diver David Shaw discovered Dreyer's body in the cave at a depth of 272 metres (892 ft). On 8 January 2005, Shaw tried to recover the body but died in the attempt. Shaw's close friend and support diver, Don Shirley, also nearly died and was left with permanent damage that has impaired his balance. On 12 January 2005, while others were recovering part of the technical equipment, they discovered the bodies of both Dreyer and Shaw had floated up close to the surface. Both bodies were recovered.
Deep diving is underwater diving to a depth beyond the norm accepted by the associated community. In some cases this is a prescribed limit established by an authority, and in others it is associated with a level of certification or training, and it may vary depending on whether the diving is recreational, technical or commercial. Nitrogen narcosis becomes a hazard below 30 metres (98 ft) and hypoxic breathing gas is required below 60 metres (200 ft) to lessen the risk of oxygen toxicity.
Cave diving is underwater diving in water-filled caves. It may be done as an extreme sport, a way of exploring flooded caves for scientific investigation, or for the search for and recovery of divers lost while diving for one of these reasons. The equipment used varies depending on the circumstances, and ranges from breath hold to surface supplied, but almost all cave diving is done using scuba equipment, often in specialised configurations with redundancies such as sidemount or backmounted twinset. Recreational cave diving is generally considered to be a type of technical diving due to the lack of a free surface during large parts of the dive, and often involves decompression.
Sheck Exley was an American cave diver. He is widely regarded as one of the pioneers of cave diving, and he wrote two major books on the subject: Basic Cave Diving: A Blueprint for Survival and Caverns Measureless to Man. On February 6, 1974, Exley became the first chairman of the Cave Diving Section of the National Speleological Society. During his career, he established many of the basic safety procedures used in cave and overhead diving today. Exley was also a pioneer of extreme deep scuba diving.
The Blue Hole is a diving location on the southeast Sinai, a few kilometres north of Dahab, Egypt on the coast of the Red Sea.
Boesmansgat, also known in English as "Bushman's Hole", is a deep submerged freshwater cave in the Northern Cape province of South Africa, which has been dived to a depth of 282.6 metres (927 ft).
John Bennett (1959–2004) was a British scuba diver who is best known for setting a world record by becoming the first person to deep dive below a depth of 300 m (1,000 ft) on self-contained breathing apparatus on 6 November 2001.
David John Shaw was an Australian scuba diver, technical diver, and airline pilot for Cathay Pacific, flying the Lockheed L-1011 Tristar, then the 747-400, and then the A330-300, A340-300, and A340-600. He flew for Cathay Pacific from 1989 until his death in 2005. Before flying for Cathay Pacific he flew for Missionary Aviation Fellowship in Papua New Guinea and Tanzania. He also flew agricultural aircraft in South Australia and New South Wales.
The Cave Divers Association of Australia (CDAA) is a cave diving organisation which was formed in September 1973 to represent the interests of recreational scuba divers who dive in water‐filled caves and sinkholes principally in the Lower South East of South Australia (SA) and secondly in other parts of Australia. Its formation occurred after a series of diving fatalities in waterfilled caves and sinkholes in the Mount Gambier region between 1969 and 1973 and in parallel to a South Australian Government inquiry into these deaths. The CDAA's major achievement has been the dramatic reduction of fatalities via the introduction of a site rating scheme and an associated testing system which was brought in during the mid-1970s. While its major area of operation is in the Limestone Coast region of SA, it administers and supports cave diving activity in other parts of Australia including the Nullarbor Plain and Wellington, New South Wales.
Agnes Milowka was an Australian technical diver, underwater photographer, author, maritime archaeologist and cave explorer. She gained international recognition for penetrating deeper than previous explorers into cave systems across Australia and Florida, and as a public speaker and author on the subjects of diving and maritime archaeology. She died aged 29 while diving in a confined space.
Artur (Conrad) Kozłowski was a Polish cave diver who spent his last years in Ireland. Amongst other achievements in cave exploration, he set the record for the deepest cave dive in Great Britain and Ireland at a depth of 103 m (338 ft).
The following outline is provided as an overview of and topical guide to underwater diving:
The following index is provided as an overview of and topical guide to underwater diving:
The following index is provided as an overview of and topical guide to underwater divers:
John Paul Volanthen, GM is a British cave diver who specializes in rescues through the Cave Rescue Organisation, South and Mid Wales Cave Rescue, and the British Cave Rescue Council. In 2018, he played a leading role in the Tham Luang cave rescue. He cave dives as a hobby and conducts rescues as a volunteer. He works as an IT consultant in Bristol.
Richard William Stanton, also known as Rick Stanton, is a British civilian cave diver who specializes in rescues through the Cave Rescue Organisation and the British Cave Rescue Council. He has been called "one of the world's most accomplished cave-divers", "the face of British cave diving," and "the best cave diver in Europe". Stanton has lived in Coventry for many years, and was formerly a firefighter with the West Midlands Fire Service for 25 years prior to his retirement. In 2018 he played a leading role in the Tham Luang cave rescue and was awarded the George Medal in the Civilian Gallantry List.