Some of the most experienced leaders in the scuba world are dead set against releasing information—let alone encouragement—on the diving methods under discussion here.
A new category of diving is taking shape in the recreational diving world that sparks controversy and is a cause of great concern. This, in general terms, is diving deeper and staying down longer than the traditional limits.
Although by no means new, for many years it was a cause for concern more than controversy. There was general agreement that it was surely dangerous, was not approved by anyone, and one could say with a clear conscience, “Don’t do it”. Now methods are coming along that, for the price of extra effort, make it possible to extend both depth and bottom time with what is regarded by some as an acceptable degree of risk, and in comparison with older methods, some tempting efficiencies.
Limits of traditional recreational diving
Recreational diving is defined by the so-called training agencies—the organizations of diving instructors (NAUI, PADI, etc.)—as no-stop scuba diving with air to 40 metres, or 30 feet. Many more experienced divers push beyond that envelope, either by doing longer bottom times that require decompression stops or by going deeper.
Although there are often some definite objectives for these dives, they are nevertheless being done for fun, so it still comes under the recreational label. It does not, however, fit within the traditional definition. A new term is needed.
The training agencies discourage the use of the term, sport diving, because it implies some sort of competition.
A colleague mentioned that he saw two young divers holding onto the bottom with their BCUs inflated, then letting go and racing to the surface. It is appropriate to discourage that sort of competition, just as it is the equally risky practice of seeing who can swim the farthest underwater in breath hold dives. Certainly, advanced divers can practice their sport without dangerous interpersonnal competition, so the term, sport diver, does not meet our needs.
Competition is indeed a motivation, not so much for the depth and time records —since nowadays they are limited to those willing to make exceptional efforts—but to be the first in an unexplored cave, or the first to look into a virgin wreck. Sport does not fit the bill here.
Two other names seem to be suitably descriptive. One is the possibly underused term, advanced recreational diving, which already has many specific meanings, but is perhaps valuable for its ambiguity.
This applies to a diver working outside the no-stop, 40-meter (130-foot) limit, regardless of the technique used. The other, high-tech diving, relates to the new methods but does not include all situations, since the traditional limits can easily be exceeded with standard gear. The task of picking a single all-inclusive term can be left to others; for now, I am calling dives outside the traditional limits advanced, and those done outside those limits using equipment other than standard wetsuits for thermal protection, as high-tech.
This includes the use of dive computers and new decompression techniques, dry suits, scooters, multiple or over pressurized tanks, as well as special gas mixtures. Use of dry suits and dive computers within the traditional depth and decompression limits can be considered traditional diving, although some special training is needed. While some of these high-tech items are relatively new to recreational diving, many of the terms are old stuff to commercial divers.
The need for competence
Considering the unforgiving nature of mistakes in diving, just talking about advanced and high tech diving has to be done with caution, lest it lead innocent lambs to the slaughter. Therefore, this general topic has to lead off with a note on competence. We cannot proceed without such a caveat.
Somehow it seems unnecessary to warn a novice skier against trying an international head-over-heels flip (some of us do them occasionally without intending to, but that is another matter). But novice divers, it seems from the accident reports do equally risky things, apparently without recognition of the risks involved. Something that may involved just a little extension beyond standard limits, if it seduces a diver into running out of air at depth, can be a great deal more risky than trying a flip on skis. Divers do these things. Therefore, allow me this bit of preaching on competence.