A Few Things Your Sport Diving Instructor May Not Have Told You About Deeper Diving
Larry "Harris" Taylor, Ph.D.
This is an electronic reprint of an article that appeared in SOURCES (Nov/Dec. 1991,p. 63-68 & THE BEST OF SOURCES, p. 37-41). It has also appeared on numerous web sites and computer bulletin boards. This material is copyrighted and all rights retained by the author. This article is made available as a service to the diving community by the author and may be distributed for any non-commercial or Not-For-Profit use.
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is an incredible fascination with diving on intact shipwrecks. In the quest for
this thrill of diving unmolested wrecks, some divers in the Great Lakes are
diving on compressed air in the vicinity of 200 ffw or deeper. A
few of these "sport divers" have taken years to develop skills,
technique and equipment that allow them to survive these penetrations into that
deep, dark, cold and silent world that lies beneath the sport diving limit of
100 - 130 Feet. A few are truly highly skilled diving adventurers. Some would
call them pioneers. Others would
call them something less dignified. It
is true that some walk with a noticeable limp, stand a little funny (numbness in
the legs), have difficulty remembering things or seem to have somehow slowed
their thinking and speech processes. None-the-less,
many of these diving adventurers have seen splendors that not many will ever
know. Other diving
"adventurers" have found unique pains and death.
new to our sport often do not realize that the successful deep diver has
generally taken a decade or more to develop the necessary skills, equipment and
technique to survive consistently this deeper diving.
Make no mistake; some of these divers are highly skilled and physically
fit. That exceptional proficiency, however, was not acquired in only a few days
or even years. Although most are
self-taught, many of these deep divers were trained when diving courses were
longer and discussions on diving physics and physiology was more extensive.
Thus, they have had access to information often missing in today's
shorter curriculum ... material
that is essential to make informed risk/benefit assessments. There are distinct physiological problems associated with
deep diving. Since divers do not
breathe water, the physiological impairments caused by deep diving can be (and
have been) life threatening. Sport
"deep diving" courses are simply insufficient training for diving to
depths "below the limits." Divers compelled to dive below 100 feet
should consider commercial or military dive training - depths below 100 feet are
beyond the realm of sport diving...Sport diving equipment and techniques no
longer are adequate! In addition,
the training agencies will not, for a variety of reasons, address the question
of training, at this time, for diving below 100-130 feet.
are those who earn their livelihood diving at depths below 100 feet. Many of
these commercial divers would consider sport divers foolhardy for diving under
conditions a professional would consider to be too dangerous. Note that
commercial operations are conducted under federal/state OSHA regulations.
Recreational and scientific diving is specifically exempted from these
regulations. (Scientific diving, however, operates under similar guidelines
promulgated by the American Academy of Underwater
Whenever any employer/employee relationship exists, these rules do apply.
This means even if the diver is volunteering services and equipment,
non-recreational, non-scientific diving may be subject to federal/state
occupational safety regulations. These
federal regulations decree that all dives more than 130 fsw (some states have
tougher regulations; Michigan, for example, places the limit at 100 feet) or any
dive requiring decompression be conducted with a tender for each diver, a
stand-by safety diver, a surface decompression chamber on the dive site, and an
adequate supply of breathing gas for the diver, the stand-by diver and the
recompression chamber. The law
specifies that the vessel used as a diving platform be Coast Guard approved and
commanded by a Coast Guard licensed operator. A designated "diving
supervisor" who insures that all OSHA regulations are met during the dive
operation must control the diving. There are additional requirements specifying
the first aid equipment, including oxygen, which must be on the dive site.
The law also requires that a complete time/event log be maintained. The
British government mandates that all diving more than 165 fsw under their
jurisdiction be done on mixed gas. In
today's liability conscious society, most legitimate diving contractors will
exceed the minimum OSHA standards.
Sciences.) Whenever any employer/employee relationship exists, these rules do apply. This means even if the diver is volunteering services and equipment, non-recreational, non-scientific diving may be subject to federal/state occupational safety regulations. These federal regulations decree that all dives more than 130 fsw (some states have tougher regulations; Michigan, for example, places the limit at 100 feet) or any dive requiring decompression be conducted with a tender for each diver, a stand-by safety diver, a surface decompression chamber on the dive site, and an adequate supply of breathing gas for the diver, the stand-by diver and the recompression chamber. The law specifies that the vessel used as a diving platform be Coast Guard approved and commanded by a Coast Guard licensed operator. A designated "diving supervisor" who insures that all OSHA regulations are met during the dive operation must control the diving. There are additional requirements specifying the first aid equipment, including oxygen, which must be on the dive site. The law also requires that a complete time/event log be maintained. The British government mandates that all diving more than 165 fsw under their jurisdiction be done on mixed gas. In today's liability conscious society, most legitimate diving contractors will exceed the minimum OSHA standards.
federal diving safety regulations prohibit non-recreational scuba operations
below 130 fsw, commercial/scientific diving is often a single diver down mode
with a tended tether, surface supplied breathing gas and some sort of dry face
mask/helmet equipped with hard wire communications. This equipment significantly
increases the safety of the diver. The communication system allows the surface
support personnel to monitor the diver's psychological and physiological status.
Surface control of the entire dive operation minimizes task loading on
the diver. This insures that potentially narcosis-free surface support personnel
make life threatening/saving decisions. The dry mask/helmet provides mechanical
and thermal protection for the diver's head and face.
More importantly, it gives the diver a dry atmosphere that is breathable
if a blackout occurs.
operations must be conducted with redundant equipment and personnel. It is this
contingency for the unexpected that increases diver safety.
This redundancy is most often missing in deep sport diving excursions.
(This equipment is beyond the finances and training of most in the sport
diving community.) Thus, the deep sport diving adventurer has very little, if
any, margin for human error.
are significant physiological problems in deeper diving. These include:
Divers have been known to suddenly lose consciousness. This may be from carbon
dioxide toxicity, carbon monoxide poisoning, severe decompression sickness,
drowning (loss of regulator because of malfunction; more likely a result of snag
or hindered regulator exchange at depth; vomiting from seasickness followed by
aspiration of seawater, etc.), hypoglycemia, hyperthermia, hypothermia, hypoxia
from equipment malfunction or miscalculation of breathing gas composition,
severe nitrogen narcosis, oxygen toxicity, pulmonary barotrauma of ascent (air
embolism), or syncope of ascent.
specific loss of consciousness under water may be due to a unique combination of
environmental, equipment or diver physiology factors. It is not possible to
predict each diver's vulnerability in absolute terms. Conditions which may
increase the likelihood of unconsciousness include:
low blood sugar, either from dieting or sustained workload, fatigue from
lack of rest or sustained workload, being too warm or too cold, dehydration,
drugs, particularly anything that has a warning label about "not operating
machinery," anxiety/fear and inexperience.
Surveys have shown that the inexperienced diver often is the most at
risk. If a commercial/scientific diver loses consciousness, he/she
continues to breathe a dry gas inside the mask/helmet; the lack of diver
response alerts the surface communicator that a problem has occurred.
Often, the communicator is aware of a problem before the diver and can
initiate steps to alleviate the problem. Two-way communication is a vital safety
feature often missing in sport diving situations. If a sport diver loses
consciousness, there is concern that a sport diver's regulator will fall out of
the mouth. The sport diver then attempts to breathe water and drowns. In
addition, the unconscious diver must depend on a buddy, if present, to insure
return to the surface.
cave diving community has noted a condition where the diver simply appears to
fall asleep. The eyes remain open; the diver does nothing but breathe. In these
cases, the regulator, for unknown reasons, has remained in the mouth. The
victims, rescued by their buddies, recall no warning signs. In the 15 reported
cases, all victims were on their deepest ever dive.
DIOXIDE (CO2) TOXICITY:
Carbon dioxide is the normal waste product of human metabolism. As more work is
done, more CO2 is generated. A person in poor physical condition may
generate 2-4 times the amount of CO2 as someone who is in excellent
physical condition while doing the same workload.
At depth, the density of the breathing gas increases. This increases the
work associated with breathing and may lead to inadequate pulmonary ventilation.
It is important for divers to realize that on scuba the CO2 comes
from internal body chemistry, not from the gas being breathed. It is the
inability of the body to eliminate this waste product that creates the problem.
This means that CO2 can be a significant problem in deeper diving.
of high CO2 usually begin with increased rate of respiration. There
is often the feeling that the regulator cannot supply enough air. This may lead
the diver to conclude falsely that an out-of-air emergency exists. This feeling
of inadequate respiration may be accompanied by a feeling of constriction around
the chest, heavy perspiration, lightheadedness, or headache.
The headache commonly is an intense pain in the center of the forehead.
This " CO2 hit," the feeling of total inadequacy to
breathe, can be a terrifying experience. Underwater
" CO2 hits" can easily lead to panic. Panic can lead to an
uncontrolled "escape" to the surface. This panicked ascent can cause a
fatal cerebral air embolism. A
diver doing work at depth, however, may have little, if any, warning of CO2
problems before losing consciousness. Again,
loss of consciousness under water in sport diving equipment has a low
probability of survival. In addition, it is believed that high CO2
increases the likelihood of decompression sickness, nitrogen narcosis and oxygen
the diver is aware that a CO2 problem is beginning to occur, the
diver should stop all activity and initiate slow, deep breathing until perceived
symptoms are eliminated. It is wise to continue resting a bit once relief is
felt and to proceed at a slower pace. Note that most experienced divers develop
a slow breathing pattern. This means a routinely high CO2 level
during diving activities. Work, coupled with poor physical condition, aggravates
the problem. It is also believed that oxygen enriched breathing mixtures can
increase CO2 retention.
MONOXIDE (CO) TOXICITY:
Despite the tendency to blame diver unconsciousness on this malady, it is rarely
observed. Carbon monoxide is primarily generated from incomplete combustion. It
can be present in the air supplied from faulty compressors (electric, as well as
gas driven) or taken into the compressor intake from a CO source such as a
kerosene heater, gas or diesel engine exhaust or cigarette smoke. The CO binds
to hemoglobin about 200 times tighter than oxygen. This means the hemoglobin
that has reacted with CO will not carry oxygen. Lack of oxygen can be fatal. The
uptake of CO is dependent on the concentration of CO in the breathing gas, on
respiration rate and the time of exposure. Symptoms may include: frontal
headache, nausea, tingling in the fingers and toes, lightheadedness, vision
disturbances or loss of consciousness with no warning. The often-quoted cherry
red lips or fingernails are a very unreliable sign and may only be visible at
autopsy. At depth the increased partial pressure of oxygen may mask some of the
hypoxia created by the oxygen deprived carboxyhemoglobin. On ascent, the
hemoglobin will still be compromised, but the decreased pO2 will no
longer compensate and unconsciousness occurs without warning.
the U.S. Navy pure air standards for breathing compressed air allow only 20 ppm
CO in scuba air. Smoke from an American cigarette typically contains about 4%
(20,000 ppm) CO. The average inhalation of a smoker contains about 500 ppm CO.
This means that finishing a cigarette just before a dive will make about
3 -7% of the hemoglobin in the blood unable to carry oxygen. The oxygen carrying
capacity of the red blood cells will be diminished for 5-8 hrs after the last
exposure to smoke. Breathing smoke,
actively or passively, will decrease the ability of the blood to carry oxygen
and this decrease in efficiency may contribute to decreased performance at
The risk of permanent tissue injury increases with depth. Many sport divers have
been given the impression that "the bends" is a benign disease. That
simply is not true. The bends can kill, but most often it cripples. The DAN
numbers show more than 500 divers a year now require chamber treatment. After 3
months post treatment, 13% of those treated still show some residual impairment.
Severe sport diver bends hits most often show spinal cord involvement.
This means that anything "South" of the lesion will be
impaired. The spinal cord mediated functions most often tainted are walking,
urinating, defecating, and sexual response.
So, if you like to walk without a cane or wheelchair, go to the bathroom
unassisted or to have sex, it is worth your while to develop some understanding
of decompression sickness and its prevention. (A recent national survey reported
in Skin Diver magazine noted that approximately 60% of those in the sport diving
community surveyed could not recognize the symptoms of the bends and almost
every survey of divers done recently suggests that more than 50% of sport divers
cannot plan dives using decompression tables.)
real danger of decompression sickness is that it is often a progressive disease;
it may continue to get worse until treated. In North America the time from onset
of recognizable symptoms to chamber treatment is often more than 12 hours. It is
this delay that can be so devastating. It is believed that the longer the delay
between onset of severe symptoms and treatment, the less the chance for total
recovery. During the delay the bubbles formed continue to impair or destroy body
functions. The key to successful recovery from the bends is immediate
recognition of symptoms and the prompt administration of the highest possible
concentration of O2 (preferably by demand mask). Medical
consultation/treatment should always be sought. Not recognizing or ignoring the
symptoms may allow the disease to do more damage. Although there are anecdotal
stories of acute relief of decompression sickness symptoms without medical
treatment, there is a lingering question of the potential for long-term damage
even though immediate clinical signs were absent or simply went away.
problems linked to decompression sickness can primarily be called "bubble
trouble." Whenever bubbles form, they obstruct normal body function. This
may prevent normal exchange of nutrients and oxygen and allows waste products to
accumulate. This can, over time, create destruction of body cells.
Medical evidence is beginning to accumulate that suggests there may be
gradual deterioration of nervous system tissue upon repeated exposure to deep
diving. It is believed that this damage can occur without ever showing gross
clinical signs (i.e. joint pain, etc.) classically associated with decompression
sickness hits. Although still far from complete, early studies seem to imply
that there is a marked deterioration in short-term memory and reasoning skills
in commercial divers aged 24-39. Autopsy
studies of three deep divers who died of non-diving related causes indicated
that there was a marked degradation of spinal cord tissue. It is believed that
the spinal cord lesions were created from diving. Although controversial, there
is some evidence that deep diving can block retinal blood flow and create vision
problems due to a damaged retina. Additional
studies measuring blood chemistry and urine of divers imply that the liver, as
well, may be damaged in divers diving as shallow as 30 meters (98 feet).
body is a remarkable biochemical machine with much redundancy. It can sustain
some tissue damage that can be compensated for by this redundancy. However,
repeated exposure to tissue-damaging conditions will ultimately result in loss
line: The DAN numbers suggest that diving below 80 fsw is a significant risk
factor for sport divers (more than 70% of DAN treatments involved sport dives to
depths below 80 fsw). The deeper and more often this deep diving occurs, the
more the risk for long-term neurological damage. It is not possible to predict
the type and severity of this physiological impairment.
Many sport divers consider the "high" associated with narcosis to be a
desirable event. This reflects a lack of understanding of the dangers associated
with breathing compressed air at depth. Nitrogen is physiologically inert (not
consumed in metabolism), but it does dissolve in body tissues. As more and more nitrogen dissolves (Remember: Henry's Law),
the abundance of nitrogen interferes with the nervous system. The more nitrogen
present, the more likely there will be a loss of performance. The result is
impairment of intellectual capacity, degradation of neuromuscular performance
and changes in mood and behavior. The
narcosis effect poses a significant danger to the diver because as it increases
the risk of an accident due to inability to perform at depth, it decreases the
diver's perception that any problem may exist.
Direct injury (aside from short term memory loss) from narcosis is
unlikely. The danger is people do
not breathe water. Under the influence of narcosis, divers may make
inappropriate decisions that place them at risk.
(Such observed diver decisions have included removal of life-support
equipment at depth.) The degradation of performance and perception caused by
narcosis is often claimed to be the primary reason for the sport diving limit of
100-130 fsw. (Historically, however, the US Navy used the 130-fsw as the limit
because this was considered the deepest depth that divers could do useful work
while breathing from a two hose style regulator (state-of-the-art at the time
the limit was imposed.))
is a marked variation in susceptibility to narcosis. This variation is not
predictable. Thus, it is not possible to equate absolutely symptoms observed
with depth. Some divers may be affected at 80 - 90 fsw or even shallower. The
effects may vary within the same diver from day to day. The physiological
degradation begins within moments of reaching depth and increases with further
descent. The higher mental
functions such as ability to reason - to make potential life-saving judgments,
to remember recent events, to learn new tasks and to focus concentration on a
specific task are first affected. (One
reason for commercial hard wire communications is so that surface personnel can
monitor a diver's ability to function and remind the diver what is to be done.)
In warm, clear water divers may first feel euphoric and overconfident (sort
of like the "Do what you will, you can't hurt me feeling") that arises
from breathing nitrous oxide (laughing gas) at the dentist's office. In cold,
limited visibility water or in water where neither the surface nor the bottom is
visible, the diver may develop a sense of foreboding or impending doom.
This sense of doom may escalate to terror and panic. As depth increases,
progressive impairment of both physical and mental skills increases. The diver
may feel drowsy. Idea fixation and hallucination may occur.
Some divers may note a narrowing of vision, like looking through a narrow
tube. It is common for a "narced"
diver to forget the reason for the dive. One reason that deep diving sport
divers take pictures is that often they can't remember what they saw on the
dive. Short-term amnesia is a
common aftereffect of narcosis. The photos (if recognizable) tell them that they
were at least somewhere near a wreck. Nitrogen
narcosis is aggravated by high CO2 levels, anxiety, cold, fatigue and
medications, particularly sedatives (anti-motion sickness remedies?) and
alcohol. There are anecdotal
reports that women will show shallower onset and increased severity of symptoms
when diving during periods of normal fluid retention.
is easily avoided by liberal applications of common sense. Simply confining
dives to shallower than 90 fsw will most likely eliminate most narcosis
problems. Ascent when symptoms are recognized will relieve the physiological
compromises that narcosis generates. Relief is generally rapid on ascent.
line: If you are human and dive below 90 fsw breathing compressed air, then your
normal human physiology will be impaired and it is impossible to predict the
severity of your inability to perform.
Oxygen is a component of the air we breathe. The body uses chemical reactions
based on oxygen to generate heat and chemical energy.
It is this process called metabolism that keeps us alive.
Oxygen reacts chemically with many different substances.
The rate at which oxygen will react (oxidation) with another chemical
compound in the body is determined, in part, by the partial pressure of the
oxygen in the breathing gas mix. As
we descend in the water column, we increase the partial pressure of all gases,
including oxygen. Reactions with oxygen will therefore increase. Some of these
oxidation products can have harmful effects on human beings. The exact mechanism
of these harmful effects is not yet understood.
oxygen concentrations affect the central nervous system in a variety of ways.
Observed symptoms, which may appear alone or in any combination, include:
nausea, vomiting, lightheadedness, dizziness that may increase to vertigo,
ringing in the ears, a feeling of impending collapse, excessive perspiration,
slowing of the heart rate, tunnel vision, muscle twitching, particularly around
the mouth and facial area, dilation of the pupils, generalized peripheral muscle
twitching, hiccups, amnesia, hallucination and mental confusion. The symptoms
can lead into a "grand mal" epileptic-type seizure. This seizure may
appear without warning. A grand mal convulsive seizure at depth in sport diving
equipment is not considered to be a survivable event.
Increased physical activity, excitement or anxiety, and being too warm at
depth apparently increase the risk of an oxygen toxicity problem.
The susceptibility of individual divers to oxygen toxicity cannot be
predicted. It is now believed to be dependent on the individual's body chemistry
on the actual day of diving. The once used "oxygen tolerance test" is
no longer considered reliable.
used to be believed that if the diver were breathing a gas containing less than
2 ATA partial pressure of O2, that potential oxygen toxicity problems
would be eliminated. This corresponds to a depth of 33 fsw for breathing 100% O2.
That is no longer current thinking. Current practice is to avoid breathing gas
that has a partial pressure of more than 1.6 ATA (19 fsw on 100% O2;
218 fsw on air) or to even a lower p O2. Oxygen toxicity seizures
have been observed in divers breathing compressed air in the 220-fsw range. This
observation suggests to avoid acute oxygen toxicity hits, dives on compressed
air should not exceed 180 fsw.
are other problems that could result from the practice of breathing pure O2
at depth (during decompression stops?). There are some medical authorities who
consider 100% O2 at elevated pressures a cellular toxin.
Breathing pure O2 at elevated pressures for extended times can
induce abnormalities in the red blood cells that carry O2 to the
body. High O2 concentrations can constrict blood vessels in the eye
and lead to visual problems. In addition, high O2 can create a mild
hearing loss that may appear hours after the dive and take a day or so to
disappear. High p O2 has
also been proposed as contributing to dysbaric osteonecrosis ("bone
death"- usually seen in deep diving commercial divers; this malady may
eventually require surgery to replace bone joints with artificial devices.)
line: The potential for grand mal seizure and subsequent death caused by oxygen
toxicity makes diving below 180 fsw in sport diving equipment on compressed air
an extremely high risk activity. Below 200 fsw many diving authorities believe
that oxygen toxicity poses a greater risk to the diver on compressed air than
This refers to the unexpected transient loss of consciousness that may be due to
partial breath holding during ascent. It
is believed to be caused by the expansion of gases within the thoracic cavity
that interferes with venous blood return. This lack of returning blood to the
heart reduces cardiac output. The reduced blood flow to the head causes loss of
consciousness. In sport diving equipment, this loss of consciousness could lead
to loss of regulator and subsequent drowning.
The effects of pressure on human physiology and psychology are often
unpredictable. Hyperbaric medicine is not yet an exact science. Divers have been
known to exhibit, for no known reason, behavior that is contrary to survival.
For example, I was with a diver along a sheer rock wall at a depth of about 25
feet of water. We had been down for 18 minutes (following a 2 hr and 10 min
surface interval from a wreck dive of 15 minutes in 40 F water at a maximum
depth of 108 feet.) We exchanged
"time-to-turn-around-and-head-for-the-dive-boat" signals (a touch to
the watch and the "thumbs up") and the diver's "O.K." The
diver then turned and headed straight for the bottom. The diver was near 60 feet before I re-established contact
and asserted control. When I caught the diver, I grabbed the shoulder and
rotated the diver so that I could see the face. It was as if I were waking the
diver from a deep sleep. The diver, even when prompted with eyewitnesses'
accounts, has no recollection of the entire episode. After several years, the
event is still unexplained.
REAL OR THEORETICAL?
There is a wreck, the Gunilda, which lies at 256 ffw in the Great Lakes.
Since it has historical significance and lies close to the Canadian
shore, the diving activity on this vessel has been monitored.
To date, there have been 26 divers who have visited this wreck. Twelve of
these divers (operating under commercial-type protocols) account for 136 dives
on this vessel. Within this group,
1 dive required treatment for severe decompression sickness (to a diver who had
34 dives on this wreck) and there were no fatalities. There have been 14 sport
divers on compressed air that have accounted for 33 dives. Of these 33 dives, 9
(27%) have resulted in severe decompression sickness that required chamber
treatment, 5 dives (15%) were aborted due to severe narcosis that required the
diver to be rescued, and there were two fatalities (6%). In addition, two of
these surviving divers, one from each group, have subsequently died on another
population of sport divers who visited this wreck is small. These divers have
seen an awesome spectacle. Not all
divers have been visibly injured. However, there were two sport diving fatalities and a high
percentage of sport divers requiring treatment for severe decompression
sickness. It would appear from this
admittedly small survey that diving to 250 ffw on compressed air does, indeed,
pose a significant risk to the recreational diver.
is most interesting to listen to these deep diving adventurers post-treatment.
One diver, after leaving the chamber against medical advice, stated that
he had experienced "no narcosis problem" at 256 ffw on compressed air.
(Remember, short-term amnesia is a common after effect.) This diver went on to
state that the bends had produced only a "mild" pain. (Perhaps the "mildness" of the pain could be
attributed to the morphine that was administered to this diver by the emergency
medical team on the flight to the chamber.)
No one has the right to restrict your personal style of recreational diving. Lee Somers, Ph.D., Diving Safety Officer for the University of
Michigan and one of the Founding Fathers of our sport, calls this "THE
RIGHT TO DIvE!" Dan Orr, Training Coordinator for DAN, calls deep sport
diving "an exercise in natural selection." The decision to risk life and spinal cord for the sake of
recreational adventure rests with each diver.
This risk (loss of life or maybe only a slight compromise in mental
faculties, the ability to walk, go to the bathroom unassisted or to have sex) /
benefit (adventure, thrill, status, or fame) decision should, however, be based
on knowledge and evaluation of the actual risks incurred and not solely on the
perceived status of survival.
once asked a very highly skilled and well-known Great Lakes deep sport diver
about diving to extreme depths on compressed air without the redundancy of
commercial equipment and personnel. My question, "What do you do alone at 250 feet under the
influence of narcosis to deal with an equipment emergency?"
His answer, "I die!" Enough said!
The decision to dive to "adventurer depths" rests with the
individual diver. Choose wisely!
The limit of 130 fsw is NOT related to physiology or any human studies. It was an estimation by the US Navy as the limit to doing useful work using a two hose regulator of the day while wearing a 72 ft3 compressed air cylinder. The US Navy manual defines "deep" as depths below 60 fsw.
author wishes to express his gratitude to Karl Huggins, Dan Orr and Lee Somers
for hours of stimulating conversation about this topic. In particular, he would
like to thank Karl for testing the capacity of his answering machine with an
impromptu discussion on the deep divers of the Gunilda.
Bennett, P. Dovenbarger, J. & Corson, K. "Etiology And Treatment Of
Air Diving Accidents," in Bennett, P. & Moon, R. (Eds.) DIVING
ACCIDENT MANAGEMENT, Undersea and Hyperbaric Medical Society, Bethesda,
MD. 1990, p. 12-22.
Bove, A. & Davis, J. (Eds.) DIVING MEDICINE, 2 nd Edition, W.B. Saunders,
Philadelphia, PA. 1990.
Edmonds, C. Lowry, C. & Pennefather, J. DIVING AND SUBAQUATIC MEDICINE, 2 nd
Edition, Diving Medical Centre, Mosman, Australia, 1981.
Exley, S. BASIC CAVE DIVING, NSS-CDS, Jacksonville FL. 1979.
Gorbett, D. "Straight Talk From A Commercial Diver," Lake Superior
Newsletter, Number 10, February-April, 1990, p. 1-3.
Hill, R.K. "Rubber Rulers", Sources, July/August, 1989, p. 37-38.
Kindwall, E. & Cumming, J. "Decompression Survey Report", guest
feature in Bove, F. "Diving Medicine," Skin Diver, March, 1989.
Monaghan, R. "Dying By Pieces-Soft Tissue Damage In Divers", Sources,
Sept/Oct, 1990, p. 48-51.
Schilling, C. (Ed.) THE PHYSICIAN'S GUIDE TO DIVING MEDICINE, Plenum Press, New
York, NY. 1984.
Somers, L. "The Depth and Gas Dilemma" In Press, NAUI IQ 1991
Somers, L. OCCUPATIONAL SAFETY AND
HEALTH STANDARD FOR SCIENTIFIC DIVING OPERATIONS, University Of Michigan, Ann
Arbor, MI. 1990.
Somers, L. "The Right To DIvE", Unpublished Manuscript, 1990.
State Of Michigan Departments Of Public Health And Labor, "A Standard For
Diving Operations," Michigan State Department Of Public Health, Lansing,
U.S. Coast Guard, "Provisions For Commercial Diving Operations,"
Federal Register, 43, (222), November 16, 1978
as reproduced in Appendix D of: Malatich, J. & Tucker, W. TRICKS OF
THE TRADE FOR DIVERS, Cornell Maritime Press, Centreville, MD. 1986.
15. U.S. Department Of Labor, "Educational/Scientific Diving Standards," Federal Register, 50 (6), June, 1985, p. 1046-1050 as supplied by the AAUS
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Divegeek Content Page: Home About "Harris" Articles Slides War Stories Editorials Links Fini
"Harris" Taylor, Ph.D. is a biochemist and Diving Safety Coordinator
at the University of Michigan. He has authored more than 100 scuba related
articles. His personal dive library (See Alert Diver, Mar/Apr, 1997, p. 54) is
considered one of the best recreational sources of information In North America.
All rights reserved.
Use of these articles for personal or organizational profit is specifically denied.
These articles may be used for not-for-profit diving education