The meaning of the term deep diving is a form of technical diving. It is defined by the level of the diver's diver training, diving equipment, breathing gas, and surface support:
- in recreational diving, the Professional Association of Diving Instructors (PADI) define anything from 18 metres (60 ft) to 30 metres (100 ft) as a "deep dive" (other diving organisations vary)
- in technical diving, 60 metres (200 ft) may be a "deep dive"
- in surface supplied diving, 100 metres (330 ft) may be a "deep dive"
This definition essentially relates to recreational diving. Deep diving may have quite a different meaning in the commercial diving field. For instance the early experiments carried out by Comex S.A. (Compagnie maritime d'expertises) using hydrox and also nitrogen trimix attained far greater depths than any recreational technical diving. One example being the Comex Janus IV open-sea dive to 500 metres (1,600 ft) in 1977. The open-sea diving depth record was achieved in 1988 by a team of Comex divers who performed pipe line connection exercises at a depth of 534 metres (1,752 ft) in the Mediterranean Sea as part of the Hydra 8 programme. These divers needed to breathe special gas mixtures because they were exposed to very high ambient pressure (more than 50 times atmospheric pressure). An atmospheric diving suit allows very deep dives of up to 700 metres (2,300 ft). These suits are capable of withstanding the pressure at great depth permitting the diver to remain at normal atmospheric pressure. This eliminates the problems associated with breathing high pressure gases.
| Depth | Comments |
|---|---|
| 40 feet (12 m) | Recreational diving limit for divers aged under 12 years old and beginner divers. |
| 60 feet (18 m) | Recreational diving limit for divers with Open Water certification but without greater training and experience. |
| 100 feet (30 m) | Recommended recreational diving limit for divers. Average depth at which nitrogen narcosis symptoms begin to appear in adults. |
| 130 feet (40 m) | Absolute recreational diving limit for divers specified by Recreational Scuba Training Council (RSTC).
Maximum depth reachable by a French level 2 diver accompanied by an instructor (level 4 diver), breathing air. |
| 180 feet (55 m) | Technical diving limit for "extended range" dives breathing air to a maximum ppO2 of 1.4 ATA. |
| 200 feet (60 m) | Maximum depth reachable by a French level 3 diver accompanied by another level 3 diver, breathing air. |
| 218 feet (66 m) | Depth at which compressed air results in an unacceptable risk of oxygen toxicity. |
| 330 feet (100 m) | Recommended technical diving limit. |
| 385 feet (117 m) | Maurice Fargues was a volunteer in a programme to determine the maximum depth a scuba diver could reach with compressed air. He became the first diver to perish using scuba. |
| 509 feet (155 m) | Record depth for scuba dive on compressed air (not officially recognised). |
| 660 feet (200 m) | Absolute limit for surface light penetration sufficient for plant growth, though minimal visibility possible farther down. |
| 1,083 feet (330 m) | World record for deepest dive on SCUBA. |
| 2,000 feet (610 m) | US Navy diver in Atmospheric Diving System (ADS) suit . |
Read more about Deep Diving: Particular Problems Associated With Deep Dives, Dealing With Depth, Ultra-deep Diving
Famous quotes containing the words deep and/or diving:
“Their very imagination was dead. When you can say that of a man, he has struck bottom, I reckon; there is no lower deep for him.”
—Mark Twain [Samuel Langhorne Clemens] (1835–1910)
“A worm is as good a traveler as a grasshopper or a cricket, and a much wiser settler. With all their activity these do not hop away from drought nor forward to summer. We do not avoid evil by fleeing before it, but by rising above or diving below its plane; as the worm escapes drought and frost by boring a few inches deeper.”
—Henry David Thoreau (1817–1862)