Technical Diving: Too Far Too Soon?
By Jeffrey Bozanic
In 1946, the first scuba units were imported into the United States. Not
until 1960 was the first national certifying agency formed, providing
instruction in the use of this equipment (Tillman and Tillman, 1995).
During the 14 intervening years, prospective divers either taught themselves
the techniques of diving, learned via written material, or had friends or
equipment salespersons give them informal lessons. By today's instructional
standards, the training from any of these sources was inadequate, or limited
at best. This resulted in numerous accidents involving novice divers.
The effect of the training agencies was to mitigate the incidence rate and
severity of these accidents (Hardy, 1975). As the agencies developed their
curricula and extended their instructor corps, effective diving instruction
began reducing the overall incident rate in diving. This resulted in diving
becoming safer, and more accepted as an activity with a reasonable degree of
associated risk. Consequently, increased numbers of people tried and stayed
in the sport.
During this same time, in the 1960's and early 1970's, many of the early,
pre-instructional era participants in this sport became very competent
divers, and went on to extend the range of their diving activities. This
commonly manifested itself in diving to increasing depths. These early
pioneers slowly accumulated the personal knowledge, experience, and skills
to accomplish their goals, and become generally competent in deep air
However, this deep diving activity slowly became a problem for the entire
scuba diving community. As deep dives were being made, they were also being
widely publicized. Soon, an attitude developed that began to equate the
depth of one's deepest dive with "prowess," effectively providing the
yardstick by which one's diving ability was measured. This resulted in many
divers overextending themselves in their diving activity, once again leading
to increased numbers of diving fatalities.
The mere fact that deep diving fatalities were increasing did not deter
newer, less experienced divers from participating in deep diving. While
some individuals and organizations attempted to promulgate caution regarding
the practice of deep diving, the psychological drive created by
community-wide peer pressure overwhelmed these individual efforts to curtail
these hazardous activities.
In part due to this, significant governmental efforts were instituted to
regulate scuba diving. In some areas of the country, proposed legislation
was successfully defeated before implementation, while in others legislation
was enacted which placed limits on diving activities. This regulation
impacted all divers, not just those engaged in "high risk" aspects of the
sport, and was viewed negatively by the sport diving community.
To combat proposed and existing legislation, the dive community began
working together to correct the underlying causes accidents. Instructional
curricula underwent another evolution in design and content. Additional
required dives were added to certification courses, and an effort was made
to modify the "macho attitude" surrounding deep diving (Somers, 1974) and
its perceived parallel to diver competence. Simultaneously, widespread
diver protest raised political awareness of the degree of
self-responsibility held by individual divers. These efforts were
successful, and as a result much of the pending and existing legislation was
either dropped or rescinded.
We have a similar situation today, with recreational divers over-extending
themselves in their diving activities. The problem is compounded by the
proliferation of nontraditional equipment and techniques used within the
recreational community. These include the use of: enriched air nitrox
(EANx) as a breathing gas (including use as primary gas, travel mix, and
decompression gas), open circuit scuba trimix (helium/nitrogen/oxygen
mixtures), stage bottle, closed and semi-closed circuit rebreathers, diver
propulsion vehicles (scooter), solo diving, decompression diving as a
routine activity, wreck and cave penetration, and once again, deep diving.
In the past these modes of diving had not been considered to have been in
the recreational diving realm. The use of these technologies today is
generally referred to as "technical diving," and participants as "technical
divers." Case histories illustrating alarming trends in the technical
diving community follow:
1. A diver walks into a dive store, and requests that his diving cylinders
be filled with EANx. He is unable to define the composition he desires, but
states, "I need it to dive a wreck at 220 [ffw] depth." Upon request, he
produces a certification card showing that he has received training in the
use of nitrox. However, his class included no diving, only lecture work.
EANx, when used as the primary breathing gas, is appropriate only for diving
relatively shallow depths. For example, NOAA Nitrox I, with an oxygen
content of 32% (EAN32), is limited by the partial pressure of oxygen
(pO2=1.6) to a maximum depth of 130 fsw. Beyond that depth, the potential
risks of acute oxygen toxicity and the consequent probability of drowning
are considered too great. The fact that this diver was unaware of this,
even after receiving training, indicates that, at least in his case, the
training was inadequate.
The International Association of Nitrox and Technical Divers (IANTD,
originally the International Association of Nitrox Divers), a training
agency specializing in the instruction of EANx for recreational scuba
divers, was formed in 1985. Since then, many other agencies have instituted
training or certification programs in EANx use, including American Nitrox
Divers, Inc. (ANDI), Technical Divers International (TDI), the Professional
Association of Diving Instructors (PADI), the National Association of
Underwater Instructors (NAUI), and others. These agencies have differing
standards for certification. This is most apparent in the number of dives
required for introductory EANx training, ranging from zero to three (0-3)
The argument used to support a course curriculum without diving requirements
is that diving on EANx is no different from breathing air. Since the
physical skills are the same, a diver who can dive on air can dive on EANx.
I disagree. While the skills associated with breathing underwater do not
change, the mindset required while EANx diving is significantly different.
EANx is much less forgiving than air in many respects, and must be treated
with a greater degree of respect. This caution is not learned by
prospective users in a class with no diving involved. In fact, I believe
that even courses with three dives are inadequate. It is my experience that
divers do not learn the basic principles of EANx use until they have
conducted four to ten (4-10) dives. This ensures that the theory of EANx
and inert gas calculations is internalized by giving them the operational
experience that makes the theory "real."
2. A diver exploring a cave system is using EAN40. The average dive depth
is 85 ffw, but ranges as deep as 105 ffw in a few short sections. There is
a significant current in the cave. During the dive, the diver is observed
convulsing. The dive buddy is unable to effectively assist the stricken
diver, who drowns. (NSS-CDS Accident files)
This fatality occurred in a diver with training in EANx use. Presumably, he
was trying to minimize his decompression obligation by diving with a high
pO2 mix. However, his maximum pO2 of 1.64 ATA exceeded the maximum accepted
limit of 1.6 ATA. In addition, he failed to consider the effects of carbon
dioxide retention and susceptibility to acute oxygen toxicity. Because he
had to fight the current during the dive, his level of carbon dioxide
retention was probably high, increasing the chances that he would experience
acute oxygen toxicity problems. For this reason, the maximum pO2 exposure
recommended for the working or exertion phase of dives is considered to be
1.2 to 1.45 ATA. His training apparently did not contain this information,
or was ignored if it did so.
3. A diver using dual single cylinders was diving air at 220 fsw. In the
course of the dive, he mistakenly switched to his oxygen decompression
regulator, convulsed, and drowned. (Anon, 1993)
4. A diver exploring a cave system was using stage bottles to extend
penetration distances. At the start of the dive, he dropped his
decompression bottle near the entrance for later use. During the exit phase
of the dive, he picked up and switched to his stage bottle. Fighting the
inflowing current, he was observed to convulse, and drowned. It was later
determined that he had left the wrong bottle at his decompression stop, and
was breathing his higher oxygen mix (EAN50) at depth (140 ffw). (NSS-CDS
Both of these cases involved the inadvertent use of the wrong breathing gas
at depth. In the first instance, the diver was breathing oxygen at a
pressure of 7.7 ATA, while in the second the pO2 was 2.55 ATA. The first
diver was required to switch regulators because of the cylinder
configuration (two independent K-valves). With this type of rig, one
alternates breathing from each cylinder to keep sufficient gas reserves in
each cylinder to effect an exit. The second diver was using two extra
single cylinders in addition to the doubles on his back, and confused the
Technical diving involves using much more equipment than standard scuba
gear. This increases task loading, placing demands on the diver far in
excess of those associated with standard air diving. Before utilizing
additional equipment, divers should first have a solid grounding with their
"standard" technical equipment, in the environment in which they are
extending themselves. Many cave divers are now "graduating" to stage bottle
use while still in their full cave class, having less than twenty cave
dives. This encourages them to continue such use once out of training.
Instead of encouraging stage bottle use, low-time technical divers should be
dissuaded from using such gear until they have attained minimal experience
5. A trained cave diver is using a scooter for the first time in a cave.
He is also carrying dual stage bottles. Within 200 feet of the entrance,
his buddy, who has no scooter, notices that the diver is no longer behind
him. Swimming back towards the entrance, he finds the diver unconscious and
not breathing near the mouth of the cave. Resuscitation attempts fail.
(NSS-CDS Accident files)
6. A diver is using a scooter for the first time to explore a wreck on a
night dive. During descent, he loses control of the scooter, which impacts
him in the head, knocking him unconscious. Unnoticed by his buddies, he
settles to the bottom and drowns. (Fernandez, 1988)
The same comments made in previous cases about progression of equipment use
apply here. In addition, in the second case the primary reason the diver
was using a scooter at all was due to the urging of his friends, who all had
scooters for the dive. In each of the cases, more benign environments
should have been used for the initial use of the equipment, i.e. open water,
daylight hours, with a basic gear rig.
7. A diver, while involved in an instructional capacity in a diving course,
makes a personal decision to make a deep air dive. During this dive he
permits several lesser experienced divers to accompany him. One of these
divers loses control while at depth (>300 fsw), but makes it back to the
surface, shaken but unharmed. (Mullaney, 1995)
The insidious problem in this case is not that an instructor, who has been
diving deep (>300 fsw) on air for many years opts to do so, but rather that
he does so openly during a program in which he is an authority figure. By
participating in that activity at that time, he tacitly encouraged other,
less experienced divers to do so as well. This unspoken peer pressure was
possibly compounded by the mindset that "if something happens, he can take
care of me" attitude that students frequently have while diving with their
instructors, even if they are not diving in formal instructor/student roles.
Deep air diving is perpetuated by the pride in which these divers esteem
themselves. Comments such as "There's only a handful of us that can handle
air at those depths [beyond 293 fsw]," (Menduno, 1993) challenge divers to
meet those same "goals," showing that they, too, are part of the diving
8. While participating in a rebreather orientation program, a diver starts
feeling lightheaded underwater, and in the process of switching to the
bailout scuba bottle, passes out. Later, it was determined that the battery
had failed, yielding an incorrect pO2 reading. Breathing was spontaneous
upon reaching the surface. (Stanton, 1996)
The introduction of rebreathers into the recreational diving community will
likely bring a series of this type of problem. Failures in closed circuit
systems are particularly insidious, as a failure may not be readily apparent
to the diver. Everything may appear to be operating acceptably, when in
fact there may be insufficient or even no oxygen in the breathing loop.
Semi-closed systems have the potential problem of divers being able to
over-breathe the units (Clarke, 1996), based on the low injection flow rates
(0.3-3.0 l/min) recommended for use. Both semi-closed and closed circuit
systems may have problems with excess carbon dioxide in the breathing loop,
from any number of causes of canister breakthrough. These problems are
compounded by the lack of oxygen sensors in some systems available on the
market, and the complete lack of a viable carbon dioxide sensor in any
system currently marketed.
Training standards for rebreather use in the recreational market have yet to
be truly field tested. To date, significant numbers of units are not
available in the market, which has hampered the development of curricula for
any given unit. While courses can be modeled on military training programs,
those programs are typically too involved and costly for the recreational
training agencies to fully adopt. Different mission objectives also impact
their suitability. This is one area in which I believe a close and
continual evaluation of the programs in use will be required.
9. A dive store contracts for the training of their instructor staff in
EANx diving and gas blending. They had no prior training in EANx use.
After six hours of instruction, they are certified as EANx diving
instructors and as EANx blenders, having made no EANx dives and having mixed
only one cylinder. Upon questioning what technique they are using to blend
gas, one of the newly certified instructor/blenders stated, "We use a
The reply made by the newly certified EANx blender implies a complete lack
of understanding of what they were "trained" to do. Unfortunately, his
comprehension of even basic EANx use was equally inadequate. The amount of
time spent with this group was, in my opinion, barely adequate to provide a
basic understanding of rudimentary EANx use, much less the level of
understanding an instructor should have. Despite the fact this instructor
had completed no EANx dives, and had demonstrated a poor awareness of basic
theory, he felt confident he could provide EANx training because he had been
given an instructor certification.
10. An person unqualified as an open circuit scuba instructor wanted
credentials as a rebreather instructor. He contacted one of the three
primary technical diving training agencies, and was turned down. Calling
upon the second, he was approved, and became a rebreather instructor over
the telephone, without any evaluation whatsoever. (Deans, 1996)
In my opinion, these last two cases are criminal! How can someone be
expected to instruct something they have little or no comprehension of
themselves? There is already a noticeable trend for technical diving
activities to be pursued by divers with decreasing amounts of experience.
now they are to be taught by instructors with little or no experience
It is difficult to provide a quantitative analysis of incidents and
fatalities in technical diving. As with standard recreational diving, while
we can quantify the number of accidents, incidents are rarely reported. In
addition, we have no firm understanding of the overall level of diving
activity. Approximated incident rates fluctuate widely, depending on the
assumptions made by the researcher performing the analysis. It is in part
for these reasons that the International Divers' Alert Network has funded
and is in the process of implementing their "Project Dive SafetyWhen
available, this data will be extraordinarily valuable for both the standard
recreational and technical diving communities. However, pending its
availability, we must rely on qualitative data. The remainder of this
discussion does just that.
The first major problem I see is the lack of training. Although the first
technical diving training agencies formed ten years ago, many of the
programs in which they offer instruction are only a year or two old. They
have had insufficient time to refine their instructional curricula, and in
my opinion some of these programs are at least in part inadequate.
The second part of the lack of training issue are the numbers of people who
are participating in technical diving activities without any training
whatsoever. This is analogous to the situations in the 1950's and 60's
where divers took their friends in the pool for "lessons," and then out to
open water to dive. Lack of appropriate training is perhaps the primary
cause of accidents in technical diving.
Peer pressure is another major contributor to the incidents we are seeing.
Within the community of technical divers, divers are once again equating the
pushing of limits with diver competency or worth. This can be inferred from
typical questions heard at gatherings of technical divers, such as: "How far
have you been in Devil's Ear?" "How deep have you been?" "What is your
longest dive?" "Haven't you used a rebreather?" "Have you dove the Doria?"
Many divers are being recruited into technical diving activities who just a
few years ago would never have considered, or been considered sufficiently
experienced for, such activities. In part, this is due to the marketing
activities of the instructors of the different technical diving agencies.
This top-down marketing approach is augmented by the grassroots interest
generated in the more traditionally oriented diving community by the
glamorization of technical diving in such magazines as Scuba Times,
aquaCorps Journal, and others.
Market pressure also drives all of the certifying agencies, to varying
degrees. The need for the agencies to build a widely based instructor corps
to capture market share is well recognized. While some of the agencies are
attempting to do so within the confines of what may be perceived as
"reasonable" limits and standards, some are, again in my opinion, grossly
overstepping these bounds. The rush to market with training programs with
new technologies, i.e. to be "the first on the block," compounds this
Once involved in technical diving, many of these lesser experienced divers
are either overtly or tacitly encouraged to overextend themselves. The slow
accumulation of knowledge, skills, and experience that is necessary to
progress deeper into the realm of technical diving is being short-circuited,
and this is leading to an inordinate number of avoidable incidents and
Where are we headed?:
I see three potential likely outcomes of the current situation:
1. Technical diving will be regionally or locally regulated out of
existence. This would be analogous to the legislation which was enacted in
the 1970's for recreational scuba diving. While it is unlikely that today
the spill over will impact "normal" recreational diving, such inclusive
regulation has already been recently proposed (Anon, 1994).
2. Federal regulation will replace regional regulation. One likely avenue
for this occurrence is via regulation by Occupational Safety and Health
Administration (OSHA). While OSHA is primarily concerned with
employer/employee relationships, the diving regulations promulgated by them
specifically exempts recreational diving, which is defined as that,
"performed solely for instructional purposes, using open-circuit,
compressed-air scuba and conducted within the no-decompression limits."
(OSHA, 1982) While these standards would not apply to individuals pursuing
personal activities, they quite possibly could be applied to dive stores
hiring instructors to teach any aspect of technical diving which exceeds
this definition, and possibly to "independent contractor" dive instructors
3. We could experience a shift in attitudes and practices regarding
technical diving, moving away from the current headlong rush forward into
these activities, replacing it with a more reasonable and considered
progression. This would be the optimal solution to the current situation.
Option 3 will not be an easy solution to achieve. We will need a
community-wide paradigm shift in order for this to occur. Such a major
change in attitude will have to begin with the leaders of the technical
diving community, specifically with the training agencies, instructors, and
major participants. This will be difficult, as it may be the perception of
these very groups that they have the most to lose from such a change in
The open water community was successful in changing previously held
attitudes regarding deep diving, and prospered as a result. The cave diving
community long had in place a "no promotion" policy, yet still provided
instruction for those who sought it out. In fact, the cave diving community
had an enviable safety record, until within the last five to eight years.
During that time, there were no fatalities among trained cave divers. Since
that time, there have been many. Perhaps it is only coincidental that this
increase in fatalities is occurring at the same time as the promotion of
cave diving courses?
Finally, in my opinion, we need to make training for technical diving
activities generally more consistent and stringent. All of the training
agencies should reevaluate their instructional programs, and as a community
evaluate the need for minimum entrance requirements, minimum skills
requirements, and minimum diving requirements for all levels of technical
diving. While this may result in fewer technical divers, it will also
result in a stronger, more competent, and safer community of divers.
The point of this paper is not to cease technical diving activities, or to
restrict personal choices made by technical divers. The main premise is
that a significant problem exists, which needs to be addressed. Divers
opting to participate in technical diving activities should obtain the
necessary background to proceed with a reasonable degree of risk. Without
an effort to control this problem, government could regulate technical
diving out of existence. As with standard open water diving in the 1960's,
there is significant room to mature in the realm of technical diving. If we
fail to do so proactively and voluntarily, we may lose the opportunity to do
so at all.
This paper was presented at the Undersea and Hyperbaric Medical Society
(UHMS) Pacific Chapter meeting held October 25-26 in San Francisco,
California. It was read in manuscript by Michael Williams, Editor of
Sources, and Billy Deans, Vice President of IANTD; I am grateful for their
valuable comments. This paper is Number 46 of the Island Caves Research
Center, Inc. Safety and Education Series.
Anon, 1993, "Incident reports," aquaCorps Journal n6 p23.
Anon, 1994, "Scuba deaths prompt calls for oversight," New York Times
(National Section), 6/5/94 p29.
Bozanic JE, 1994, "Cave diving fatalities," in Van Hoesen K (Ed),
Proceedings of the 22nd Annual UHMS Pacific Chapter Meeting, UHMS, 5p.
Clarke J, 1996, Personal Communication, Rebreather Forum 2.0, Redondo Beach,
CA, Medical Director, U.S. Navy Experimental Diving Unit, Panama City, FL.
Crosson D, 1996, Personal Communication, President, Delta-P, Ft. Pierce, FL.
Deans B, 1996, Personal Communication, Rebreather Forum 2.0, Redondo Beach, CA.
Fernandez R, 1988, Personal Communication.
Hardy J, 1975, "Some true facts on scuba diving," NAUI News, May, p20.
Menduno M, 1993, "To air is human?," aquaCorps Journal n7 p5.
Mullaney D, 1995, "Call of the wah wah," aquaCorps Journal n11 p77-82.
NSS-CDS Accident files, 1960-96.
OSHA, 1982, 29 CFR §1910.401(a)(2).
Somers L, 1974, "The deep diving syndrome," NAUI News, Apr/May, p3-4.
Somers L, 1996, Personal Communication, Diving Safety Officer, University of
Michigan, Ann Arbor, MI.
Stanton G, 1996, Personal Communication, Diving Safety Officer, Florida
State University, Tallahassee.
Tillman A and T Tillman, 1995, "A history of the National Association of
Underwater Instructors," Unpublished Manuscript.
About the Author:
P.O. Box 3448
Huntington Beach, CA 92605-3448
Jeff serves as the Executive Director of Island Caves Research Center, a
non-profit organization formed for the purpose of conducting scientific
investigations in submerged cave systems. His research diving activities
have taken him to the Bahamas, Palau, Guam, Mexico, Canary Islands,
Antarctica, and other worldwide locations. Jeff was certified as a NAUI
Instructor in 1978, and as a cave diving instructor in 1983. He is
certified to teach cave diving for the NSS-CDS, NACD, and NAUI. He is
active in teaching nitrox, technical nitrox, and trimix diving courses. He
has published extensively on diving education topics, with heavy emphasis on
cave diving safety techniques. He has edited/reviewed many diving
textbooks. He has served on several Boards of Directors in the diving
community, including as Chairman of the NSS-CDS and as Vice Chairman of
NAUI, and currently serves as Treasurer on the AAUS Board. He has received
the NAUI Outstanding and Continuing Service Awards; and the Silver Wakulla
and Abe Davis Awards for safe cave diving.