Diving Unlimited International
Description:Manufacturing defects in the lanyard
connecting the handle to the pocket or the cable securing the pocket to the
harness can prevent the weight pockets from easily detaching from the harness
and releasing the weights when the handle is pulled. This poses a drowning
hazard to consumers.
Units: About 1,454 in the U.S. and
46 in Canada
The weight harnesses are made of heavyweight nylon and are
black in color with gray handles. The DUI logo appears on the pockets. The
Weight & Trim System Classic has two small weight pockets on each side. The
Weight & Trim System II has one large weight pocket on each side.
Systems with large silver stripes on the sides have been inspected or
repaired and are not affected by this recall.
Sold at:
Diving equipment retailers nationwide and in Canada between July 2010 and April
2011 for about $124.
Consumers should immediately stop using the
systems. For additional information, contact DUI Customer Service between 8 a.m.
and 5 p.m. PT Monday through Friday at (800) 325-8439, by e-mail at
CustomerService@DUI-Online.com or visit www.DUI-Online.com
I created this blog as a place to store dive related information, such as technical diving, decompression theory, equipment configuration, etc...
2 Mayıs 2012 Çarşamba
OMS recall alert
OMS Buoyancy Compensators
Description:The buoyancy compensator seal ring could crack. The compensators were sold in black or red. “OMS” is printed on the front inside of the compensators. Item and serial numbers are printed on the warning label located in the non-inflation area of the buoyancy compensator. A list of serial numbers included in this recall is available from the firm. This recall involves buoyancy compensators with the following model numbers.
Units:
About 20,000
Sold at: Dive stores nationwide from May 2006 through August 2008
For additional information, contact Ocean Management Systems toll-free at (877) 791-0315 between 9 a.m. and 4:30 p.m. ET Monday through Friday, visit the firm’s website at www.omsdive.com, or email the firm at recall@omsdive.com
Description:The buoyancy compensator seal ring could crack. The compensators were sold in black or red. “OMS” is printed on the front inside of the compensators. Item and serial numbers are printed on the warning label located in the non-inflation area of the buoyancy compensator. A list of serial numbers included in this recall is available from the firm. This recall involves buoyancy compensators with the following model numbers.
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|
Sold at: Dive stores nationwide from May 2006 through August 2008
For additional information, contact Ocean Management Systems toll-free at (877) 791-0315 between 9 a.m. and 4:30 p.m. ET Monday through Friday, visit the firm’s website at www.omsdive.com, or email the firm at recall@omsdive.com
26 Nisan 2012 Perşembe
Miflex High Pressure Hose Recall
Miflex High Pressure Braided Scuba Diving HosesIn Cooperation With United States CPSC and Health Canada
If you have one or more of the recalled hoses, you should immediately stop using it.Follow these simple instructions to receive a factory-authorized replacement high pressure hose or call Toll Free 888-249-5404 during normal business hours PST. To contact us via email click here.
- Download a Return Form.
- Fill out on your computer and print a copy.
- Include the form with your hose(s) and return to XS Scuba (address located on form).
- Replacements will be sent to you in about 2-3 weeks.
HOSES CAN RUPTURE REDUCING THE AVAILABLE AIR SUPPLY TO THE DIVER, POSING A DROWNING RISK
This recall involves hoses sold after May 2009 within Canada, The United States and U.S. Territories. Primarily these hoses were sold as individual replacement gauge hoses. Additionally, they were sold as Cascade Hoses, Deluxe Cylinder Equalizer (P/N AC366), Miflex Two Gauge Console (HL300/HL300M) and Miflex Rebreather Kits.MiFlex Low Pressure Hoses are not affected by this recallMiflex high pressure hoses can be identified by:1. A black nylon braided outer covering on the hose2. A hose diameter of approximately 1/4 inch (6mm)3. Manufacturing stamping on the female fitting "MFX"
27 Mart 2012 Salı
Parker Turner
Indian Spring’s Dive Accident Analisis
By Bill Gavin
Our dive at Indian Springs was the first in a series of exploration dives
that had been in the planning stages for nearly two years. Because of
the unique profile of the cave and the extreme depth at the point at
which actual exploration would take place special decompression
tables had been generated by Dr. R.W. Hamilton. The dive plan
consisted of a 40 minute transit at 140 FSW while breathing an EAN 27
travel mix (27% oxygen, balance nitrogen), a descent and exploration
at 300 FSW using trimix 14/44 (14% O2, 44% He, balance N2) followed
by the return 40 minute transit to exit the cave. The deep working
phase of the dive was expected to last 20 to 25 minutes. The 140 FSW
penetration and exit was done using two 80 cubic feet “stage” bottles,
while the deep portion was accomplished using back mounted double
104′s.
The dive went almost exactly according to plan during the penetration.
The deep section known as “Wakulla Room” was explored in three
different directions. None of these yielded any going tunnel or
evidence of flow. We began our exit at 63 minutes into the dive. At this
time I had 2300 psig in my double 104′s and I assume that Parker had
the same or slightly less. We reached our nitrox bottles at the top of
the room in two to three minutes, began breathing them, and did not
use our doubles again until we encountered the obstruction at what is
known as the “Squaws Restriction.” After picking up our second stage
bottle during the exit, Parker signalled that his Diver Propulsion Vehicle
seemed to be running slow. We linked up via a tow strap and I
increased the speed setting on my DPV to maximum. We were only
about 1500 feet from the entrance, so this did not present a serious
problem.
There is a distinctive arrow marker at the upstream/downstream
junction which is about 500 feet from the entrance. As this arrow came
into view, I remember estimating that our bottom time was going to be
somewhere between 105 to 110 minutes. We made the left turn at this
arrow and immediately noticed that the visibility in the cave had
decreased. The floor was completely obscured by billowing clouds of
silt, but the line was still in clear water near the ceiling. As we got closer
to the entrance, the visibility got progressively worse. Finally, we had to
stop using the DPV and swim while maintaining physical line contact.
When we got to where I thought the restriction should be, the line
disappeared into the sand on the bottom of the cave. We began pulling
the line out of the sand, but some reached a point where it was buried
too deep. Visibility in this area was 1 foot or less. I heard Parker shout
into his regulator, “What’s this?” We backed up out of the low area and
removed our stage bottles and scooters. At about this time, the second
bottle that I had been breathing during the exit ran out. Realizing that
the situation was not going to be quickly resolved, I elected to switch
immediately to my doubles, which still had about 2000 psig of gas.
There were two lines running parallel in the cave at this point. We tried
following both of them, but each time got to a point where the line could
not be pulled from the sand which had covered it.
I secured the line from the reel that we had carried with us to the end of
the permanent line (where it was buried) and tried to search for a way
out. The restriction seemed to be completely blocked with sand and
perhaps rock. The visibility was so bad that we could not really figure
out exactly where we were or what had happened. However, there was
flow and I tried to follow that. After finding no way past the blockage, I
began to have doubts about our exact location. It seemed as though
we must have made some mistake. While Parker continued to search, I
swam about 300 feet back into the cave until I saw the
upstream/downstream arrow marker. Though this marker is quite
distinctive, I had to stare at it for a few seconds to convince myself that
I really knew where we were. I swam back to the point where we had left
our bottles and scooters. Parker was waiting there.
I am not sure how many attempts we made to retrieve the buried line,
but at least 45 minutes passed while we sought in vain for some way
out. At one point Parker showed me his pressure gauge which
indicated about 400 psig of gas remaining in his doubles. He wrote on
his slate, “What do we do?” I knew he was hoping I had some idea, but
the only thing I could think to write back was “Hold on. I’ll go look.”
I went back to search using my reel and sweeping left and right.
Finding no exit, I decided to return to the stage bottles, which at least
had a little more gas to offer. I had been gone for less than five
minutes. When I returned to the bottles, Parker was not there. I found
my second stage bottle, which had about 600 psig left in it. I began
breathing it while trying to think of some plan. After about four minutes
it ran out and I switched back to my doubles, which now had less than
300 psig of gas. With no other alternative, I decided to try one last
effort at finding an opening. As I started back out I saw that another
line had be “Tee’d” into the permanent line. I followed it without really
understanding how it had gotten there. I reached a point at which the
cave seemed to open up and saw something hanging down on the
edge of my vision. As I swam under the object it dimly occurred to me
that it was the second stage of a scuba regulator. By now my doubles
were almost empty and my regulator caught on my manifold as I
passed. I rolled to my left to free it. At this point, I looked up and saw
the permanent line rising at a sharp angle. I realized that I had cleared
the restriction and raced to our decompression bottles, which were
hung at 100 feet. I was almost holding my breath by the time I
unclipped the second stage and began breathing from my first
decompression bottle. Parker was not at the bottles and I realized at
this time that he had drowned.
The regulator that had caught on my manifold was from his doubles,
which he had removed and dragged through the small opening. I had
no idea where Parker was and the visibility was still less than two feet.
Numbly, I waited for support personnel to find me. In the confusion that
followed, many lines were laid throughout the cavern area by our
support divers in attempt to locate Parker’s body. Despite their efforts,
he was not found until the following morning when visibility had
increased to about 10 feet. It had been 60 feet or better when we
started our dive.
During the four hours of decompression that followed, I was gradually
filled in on the situation by our support crew. Without their efforts, I
think I would have gone mad wondering what had happened. For a
long time I did not know if the entire entrance to the cave had collapsed
or if anyone else was missing. I also had no idea what kind of
decompression to follow. Though I fully expected to suffer
decompression sickness, I emerged from the water with no physical
damage. Apparently the fact that we had been shallower than expected
during our deep exploration saved me from that malady.
By Bill Gavin
Our dive at Indian Springs was the first in a series of exploration dives
that had been in the planning stages for nearly two years. Because of
the unique profile of the cave and the extreme depth at the point at
which actual exploration would take place special decompression
tables had been generated by Dr. R.W. Hamilton. The dive plan
consisted of a 40 minute transit at 140 FSW while breathing an EAN 27
travel mix (27% oxygen, balance nitrogen), a descent and exploration
at 300 FSW using trimix 14/44 (14% O2, 44% He, balance N2) followed
by the return 40 minute transit to exit the cave. The deep working
phase of the dive was expected to last 20 to 25 minutes. The 140 FSW
penetration and exit was done using two 80 cubic feet “stage” bottles,
while the deep portion was accomplished using back mounted double
104′s.
The dive went almost exactly according to plan during the penetration.
The deep section known as “Wakulla Room” was explored in three
different directions. None of these yielded any going tunnel or
evidence of flow. We began our exit at 63 minutes into the dive. At this
time I had 2300 psig in my double 104′s and I assume that Parker had
the same or slightly less. We reached our nitrox bottles at the top of
the room in two to three minutes, began breathing them, and did not
use our doubles again until we encountered the obstruction at what is
known as the “Squaws Restriction.” After picking up our second stage
bottle during the exit, Parker signalled that his Diver Propulsion Vehicle
seemed to be running slow. We linked up via a tow strap and I
increased the speed setting on my DPV to maximum. We were only
about 1500 feet from the entrance, so this did not present a serious
problem.
There is a distinctive arrow marker at the upstream/downstream
junction which is about 500 feet from the entrance. As this arrow came
into view, I remember estimating that our bottom time was going to be
somewhere between 105 to 110 minutes. We made the left turn at this
arrow and immediately noticed that the visibility in the cave had
decreased. The floor was completely obscured by billowing clouds of
silt, but the line was still in clear water near the ceiling. As we got closer
to the entrance, the visibility got progressively worse. Finally, we had to
stop using the DPV and swim while maintaining physical line contact.
When we got to where I thought the restriction should be, the line
disappeared into the sand on the bottom of the cave. We began pulling
the line out of the sand, but some reached a point where it was buried
too deep. Visibility in this area was 1 foot or less. I heard Parker shout
into his regulator, “What’s this?” We backed up out of the low area and
removed our stage bottles and scooters. At about this time, the second
bottle that I had been breathing during the exit ran out. Realizing that
the situation was not going to be quickly resolved, I elected to switch
immediately to my doubles, which still had about 2000 psig of gas.
There were two lines running parallel in the cave at this point. We tried
following both of them, but each time got to a point where the line could
not be pulled from the sand which had covered it.
I secured the line from the reel that we had carried with us to the end of
the permanent line (where it was buried) and tried to search for a way
out. The restriction seemed to be completely blocked with sand and
perhaps rock. The visibility was so bad that we could not really figure
out exactly where we were or what had happened. However, there was
flow and I tried to follow that. After finding no way past the blockage, I
began to have doubts about our exact location. It seemed as though
we must have made some mistake. While Parker continued to search, I
swam about 300 feet back into the cave until I saw the
upstream/downstream arrow marker. Though this marker is quite
distinctive, I had to stare at it for a few seconds to convince myself that
I really knew where we were. I swam back to the point where we had left
our bottles and scooters. Parker was waiting there.
I am not sure how many attempts we made to retrieve the buried line,
but at least 45 minutes passed while we sought in vain for some way
out. At one point Parker showed me his pressure gauge which
indicated about 400 psig of gas remaining in his doubles. He wrote on
his slate, “What do we do?” I knew he was hoping I had some idea, but
the only thing I could think to write back was “Hold on. I’ll go look.”
I went back to search using my reel and sweeping left and right.
Finding no exit, I decided to return to the stage bottles, which at least
had a little more gas to offer. I had been gone for less than five
minutes. When I returned to the bottles, Parker was not there. I found
my second stage bottle, which had about 600 psig left in it. I began
breathing it while trying to think of some plan. After about four minutes
it ran out and I switched back to my doubles, which now had less than
300 psig of gas. With no other alternative, I decided to try one last
effort at finding an opening. As I started back out I saw that another
line had be “Tee’d” into the permanent line. I followed it without really
understanding how it had gotten there. I reached a point at which the
cave seemed to open up and saw something hanging down on the
edge of my vision. As I swam under the object it dimly occurred to me
that it was the second stage of a scuba regulator. By now my doubles
were almost empty and my regulator caught on my manifold as I
passed. I rolled to my left to free it. At this point, I looked up and saw
the permanent line rising at a sharp angle. I realized that I had cleared
the restriction and raced to our decompression bottles, which were
hung at 100 feet. I was almost holding my breath by the time I
unclipped the second stage and began breathing from my first
decompression bottle. Parker was not at the bottles and I realized at
this time that he had drowned.
The regulator that had caught on my manifold was from his doubles,
which he had removed and dragged through the small opening. I had
no idea where Parker was and the visibility was still less than two feet.
Numbly, I waited for support personnel to find me. In the confusion that
followed, many lines were laid throughout the cavern area by our
support divers in attempt to locate Parker’s body. Despite their efforts,
he was not found until the following morning when visibility had
increased to about 10 feet. It had been 60 feet or better when we
started our dive.
During the four hours of decompression that followed, I was gradually
filled in on the situation by our support crew. Without their efforts, I
think I would have gone mad wondering what had happened. For a
long time I did not know if the entire entrance to the cave had collapsed
or if anyone else was missing. I also had no idea what kind of
decompression to follow. Though I fully expected to suffer
decompression sickness, I emerged from the water with no physical
damage. Apparently the fact that we had been shallower than expected
during our deep exploration saved me from that malady.
Sheck Exley
Under
Pressure
Scuba
had finally come full circle: from the first explorers who strapped on archaic
tanks back in the 1950s to technical divers who now strapped on underwater
computers and dive to depths so great the pressure could crush a car faster than
a five-car pileup.
By
Jerry Shine
In
an underwater cave somewhere beneath Mexico, two divers, Sheck Exley and Jim
Bowden, are squeezing through a narrow crevice toward a light ahead. The light
comes from an opening, an entrance into a second cave known as Zacatón, whose
abyssal depths almost defy description.
Exley
and Bowden pass through the opening, then rise to the water’s surface 25 feet
above, emerging into a circular pool surrounded on all sides by rocky walls that
reach up through the water 70 feet into the air. The stark beauty of Zacatón’s
cliffs, sun-baked and baron, is breathtaking but the divers’ true interest lies
at its bottom, 1,080 feet down.
Bowden,
a 54-year-old Texan whose hair and beard have long since turned an ivory white,
has devoted much of his life to exploring underwater caves such as this
throughout Central America and Mexico. In this part of the world, if it’s
underground and underwater, he’s probably been there. Caves are his love and his
life, and just about every penny he earns is poured into them. Anything left
over at the end of the month he uses to take care of the more mundane things,
like his electric bill.
Bowden’s
partner, Exley, is universally regarded as the Michael Jordan of cave diving. An
exceedingly open man to those he knows, intensely private to those he doesn’t,
Exley is an enigma in the diving world: he holds virtually every cave-diving
record (in terms of depth and penetration), yet he wants no publicity for those
records. His average build belies the tough martial arts workouts he puts
himself through daily to prepare for the rigors of his obsession. Rigors he
knows well. At 45, he’s spent more time in underwater caves than most fish. His
passion for these caves is legendary, but beyond that he has a supreme, natural
ability to operate within their confines. Most divers, even highly trained ones,
lose a certain percentage of their land skills once they dip beneath the water’s
surface. Not Exley. His transition from one medium to the next is as effortless
as it is complete – over the course of some 3,000 dives, he’s worked his way out
of enough life-threatening situations to give Jacques Cousteau an inferiority
complex.
Exley
is also something of a reluctant standard-bearer for the new sport of technical
diving: a subculture of mission-oriented divers who use technology to plunge to
ungodly depths. Unlike the typical recreational diver who spends his free time
dreaming of vacations in the Caribbean, technical divers are more likely to be
found searching the Internet for information on diving computers, heads-up
displays, rebreathers, and portable recompression chambers. They use complex
software to plan their descents, carry US$10,000 to $15,000 worth of equipment
with them into the water, and place themselves in situations well beyond the
capabilities of the average recreational diver.
At
first glance, they may seem possessed of potentially fatal amounts of
testosterone. But, in the last few years, their ranks have mapped out some of
the world’s deepest underwater caves and descended on such previously undiveable
wrecks as the Monitor and the Lusitania.
No
technical diver, however, not even Exley, has reached the depths of Zacatón,
where hydrostatic pressure hits 487 pounds per square inch (compared with 14.7
pounds per square inch at sea level). Pressure this great can implode even the
best diving equipment as easily as you could crush a styrofoam cup.
Its
effects on the body can be just as dramatic, making the range of physiological
barriers read like an inventory of hyperbaric nightmares: decompression illness
(a k a the bends), oxygen toxicity, high-pressure nervous syndrome, deep-water
blackout, and nitrogen narcosis. Any of these can result from breathing air or
other gases under extreme pressure. To combat these dangers, Exley and Bowden
have spent the last year going over every detail of the dive, attempting to make
it, if not safe, at least survivable.
It’s
April 1994. Their dive plan is fairly straightforward: each diver will drop down
into the near-vertical cave under the weight of 200 pounds of gear, maintaining
visual contact with the weighted line anchored to the bottom.
At
these depths, the inert gases in their breathing mixtures will be rapidly
absorbed into their bloodstreams. Water pressure will keep those gases
compressed in the form of small, harmless bubbles – that is, until the divers
return to the surface.
If
they ascend too quickly, the decreasing water pressure will cause the gases to
bubble up out of the solution like a can of soda shaken before being opened.
The
result is the bends: an excruciatingly painful, often fatal, condition.
To
avoid this, Exley and Bowden, after touching the bottom, will rise to the
surface slowly, making “decompression stops” at predetermined depths for
specific periods of time; this will allow the gases to come out of the solution
gradually. The entire process will keep them underwater for more than 10 hours.
The
key is a speedy descent. The faster they reach the bottom and then start back up
again, the less gas is absorbed. To that end, they’ll drop at a rate of 100 feet
per minute. Put into perspective, a commercial diver descending to 1,000-plus
feet would breathe through a surface-supplied hose and take upward of 24 hours
to reach his destination. Exley and Bowden will be there in 12 minutes.
Another
problem is air supply. Because divers can’t carry 10 hours’ worth of gas on
their backs, dozens of extra tanks – each holding a different mixture designed
to speed decompression – are tied into the two descent lines at the various
decompression stops. Even with these extra tanks, however, if either diver takes
more than six breaths per minute at any point during the descent, he’ll run out
of gas long before making it back to the surface.
The
late morning sun is cresting over the ridge surrounding Zacatón as Exley and
Bowden complete their equipment check. They’re ready. One last nod to each other
and under they go, heading down, down, and down some more through mineralized
sulfur clouds held in suspension, through warm water growing ever darker. At 230
feet, they maneuver around a ledge and all light fades to black. Flashlights now
cut through the darkness. Minutes pass. Hurtling downward silently, Bowden
checks his pressure gauge at 850 feet and suddenly realizes he’s used up his
breathing mix much faster than expected. There’s no time to figure out why. He
may have enough to reach the bottom, but not enough to make it back up. To
continue on would be suicide. It may already be too late.
He
begins inflating his buoyancy compensator – the “BC” is a collapsible vest used
to control buoyancy – but momentum and the 200 pounds of equipment he’s wearing
carry him deeper. He sails past the 900-foot mark. To kick or swim would be
fatal at this depth; the carbon dioxide generated by the exertion would cause an
almost instant blackout. He can do nothing but hit his BC – and hard. Finally,
he reaches out to grab the line; as the 925-foot mark slips through his fingers,
he comes to a stop. Little by little, the inflator begins lifting him back up
through the darkness and eventually into water broken by sunlight. He sees
Exley’s descent line 25 feet away. He also sees Exley’s staged decompression
tanks tied into it, waiting for him. But he doesn’t see Exley.
The
men and women who pioneered the sport of scuba diving in the 1950s were hard-ass
explorers in every sense of the word. The technology was new. Its limitations,
and those of the human body while using it, were largely unknown. Early divers
pushed these limitations as far as they could, and then some. Within 30 years,
they could be pushed no more: scuba experts were reaching depths in excess of
300 feet.
It
was physiologically impossible to go much deeper breathing air. At such depths,
nitrogen – otherwise harmless – transforms into a mind-numbing narcotic. Oxygen,
too, becomes toxic, poisoning the central nervous system and sending the body
into convulsions. The only way to go deeper is to add varying amounts of other
inert gases – helium, hydrogen, or neon – into the mix.
The
stumbling block was decompression. Since these other inert gases are absorbed
into the body at rates different from nitrogen, the standard sport-diving
decompression tables – schedules of decompression stops which allow safe
absorption of the different gases to avoid the bends – didn’t apply. And there
were no alternative mixed-gas tables. That left divers with two choices: stick
with air and dive no deeper than current limits, or take a chance using mixed
gas and a homemade decompression schedule.
The
chance was not a small one. It is critical that divers use the right mix of
gases, in sufficient quantity, at the correct time and depth. Even minor
decompression mistakes can be deadly, and using mixed gas was akin to a game of
Russian roulette.
In
the spring of 1988, six years before the Zacatón dive, Sheck Exley entered
Nacimiento del Rio Mante, an underwater cave in Mexico, with four huge tanks
containing a mixture of helium, nitrogen, and oxygen strapped to his back and
sides.
(He
would use 21 tanks and 11 different gases in all.) Exley had already made
several mixed-gas dives over the last year, but this was the first one he would
make with a decompression schedule developed specifically for him.
“We
were so far off the charts (in terms of depth and duration) that we were going
on gut feeling,” remembers Bill Hamilton, editor of Pressure, the Undersea and
Hyperbaric Medical Society newsletter, who developed the dive plan for Exley.
“The computer would spit out numbers but we couldn’t take them at face value –
they weren’t based on actual exposures,” he recalls. “So we manipulated them,
worked around them, interpolated between them – you know, all the things you’re
not supposed to do – and, eventually, we got a dive plan out of them.”
From
previous, shallower dives, Exley already knew the hazards of Mante. Silt, which
if disturbed could obliterate visibility for hours, lined the cave floor, while
the jagged edges of the cave wall jutted out from each side. Strong, upward
currents slowed his descent to 30 feet per minute.
As
he went down, the cave’s shape began to hourglass – growing wider then narrower
then wider again – while maintaining its near-vertical drop. His goal was to
dive beyond 700 feet, deeper than any scuba diver had been before.
Twenty
minutes later, Exley passed below the 700-foot mark, even as the narcotic
effects of the nitrogen crowded his senses. Suddenly, an explosion behind his
head knocked him almost unconscious. He steadied himself against the wall of the
cave and tried, without luck, to locate the problem.
He
checked his depth gauge. He was now at 780 feet. Whatever the explosion was, it
was time to head back. He rose quickly into shallow water (shallow being a
relative term) and began his decompression, breathing from tanks he had staged
along the way, each of which contained the precise gas mixture registered on
Hamilton’s decompression schedule.
Timing
was essential. To linger too long, or not long enough, at any one stop would be
an open invitation to the bends, so he kept a close eye on all three of his
watches. Wearing three watches was a habit he’d picked up the year before when
he lost his only watch mid-dive; this forced him to count off each decompression
stop in his head. One-one-thousand, two-one-thousand, three-one-thousand….
Luckily, he had to do it for only a couple of hours.
And
the explosion? A Plexiglass case housing the motorcycle battery that powered his
flashlight had imploded. It just couldn’t take the pressure.
Would
you venture out into the unknown out of greed? Greed works only in the world of
ordinary affairs. To venture into the terrible loneliness, one must have
something greater than greed. Love. One needs love for life, for intrigue, for
mystery. One needs unquenching curiosity and guts galore.
With
that somewhat purple prose from Carlos Castenada’s The Fire from Within, Michael
Menduno, a former marketing executive going through a mid-life crisis, launched
aquaCorps, a dive magazine with an attitude, in 1990.
Until
that moment, in the 40-plus years since Jacques Cousteau had introduced the
world to the scuba tank and underwater adventure, diving had steadily evolved
from the province of exploration to that of a tame, organized activity,
generating millions of dollars on the sale of equipment and travel vacations.
New diving rules, established by training agencies and bolstered by dive
magazines (the sport’s new power structure), were set in stone in the 1960s:
never dive deeper than 130 feet, never dive alone, never get into decompression
situations.
The
sport of rugged individualism, of Lloyd Bridges on the old TV show Sea Hunt,
soon had an accident rate lower than that of bowling. All vestiges of the bad
old days, of explorers diving by the seat of their wet-suit pants, were stricken
from the record; people entering the sport had no idea that things were ever
done any other way.
Michael
Menduno’s aquaCorps took a different approach. Its standard fare included mixed
gases, improved decompression methods, treatment strategies for the bends, and
fatality reporting – topics that no other magazine had touched in decades. In
one fell swoop, all those divers your mother warned you about now had a pulpit
from which to preach.
“People
who were already into deep diving and mixed gases grabbed it up,” says Menduno.
“But the powers that be, well, they were a little cautious.”
A
little apoplectic would be a better description. Angry, almost hysterical,
editorials filled the pages of other dive magazines. Manufacturers of some types
of mixed-gas equipment were banned from the industry’s annual trade conference,
to be reinstated later only under the threat of legal action.
By
the time the second issue of aquaCorps hit the stands, Menduno had christened
the unnamed sport “technical diving.” Even as he did, it became clear that it
was far less forgiving than its gentler predecessor. In the summer of 1992,
eight divers in the US died during deep or mixed-gas dives. There were other
deaths in Europe.
Nevertheless,
the tide had turned. The allure of exploring virgin and near-virgin caves,
wrecks, and reefs, all the while pushing personal limits to the edge, testing
them, extending them, was too powerful to ignore. Training agencies for
technical diving were being established. aquaCorps launched tek, an annual
conference that began drawing divers from around the world. Even the more
mainstream dive magazines were touching on previously taboo technical-diving
topics. And as more deep, mixed-gas dives were conducted, data on their limits
were accumulated and disseminated, eliminating some of the old dangers as newer
ones beckoned.
By
1993, the growth of technical diving vaulted Sheck Exley to legendary status.
“He was walking on the dark side of the moon compared with everyone else,” says
Bret Gilliam, a longtime friend of Exley and CEO of Technical Diving
International. “When he made his original Mante dive, not only did he go deeper
than anyone had gone before, but his first decompression stop was deeper than
anyone had ever been.” Among technical divers, it was becoming clear that Sheck
Exley was The Man.
In
the summer of ’93, he used a decompression schedule developed with his own
software to dive a South African water-filled sinkhole called Bushmansgat.
Squeezing through a 3-foot crack to enter it, he picked up speed and descended
200 feet into the world’s largest underwater cavern. Even to Exley, its size was
overwhelming.
He
continued down, at a rate faster than ever before. At 700 feet, however, Exley’s
body lodged a severe protest. Hundreds of small concentric circles, each with a
sparkling dot at its center, filled his vision. His body began itching and
stinging. It was high-pressure nervous syndrome, a little-understood phenomenon
brought on by severe, rapid compression. The extreme pressure inhibits the
function of the brain, causing neural circuits to run wild. Exley had never
experienced it before.
He
hovered at 750 feet, to consider his options: abort or continue down. Decision
made. He started down again, more slowly this time, though there was little
physical change. By the time the cave bottomed out at 863 feet, Exley’s entire
body had begun shaking uncontrollably.
Exley
ignored it. His flashlight cut through the darkness. Even without full vision,
he could make out what appeared to be a lunar landscape: a uniformly flat
bottom, sloping away from him, covered with small rocks, and buried in nearly a
foot of black sediment. No one before him had ever stood where he was standing.
He
couldn’t stay long, since every minute of extra time he spent at that depth
would eventually have to be paid for with extra hours of decompression. After a
good look around, he inflated his BC and began to rise. He was more than halfway
to the surface before the syndrome subsided.
At
Zacatón, 100 feet beneath the water’s surface, Jim Bowden hovers at his
decompression stop. Above him, the sun has set below the ridge surrounding the
cave.
A
support diver moves in close and begins gesturing to him. As she does, the
silent motions of her fingers weave a message that he already knows in his heart
but has tried not to believe. Sheck Exley, the man who read paperback novels
underwater to pass the time during long decompression stops, the man who
celebrated New Year’s Eve for the last 25 years in dozens of underwater caves
throughout Florida and who rescued countless other divers from near-fatal
situations, has not come up. Sheck Exley is dead.
Bowden
continues to hover. He can’t head back down for Exley; he doesn’t have the gas
supply. He can’t surface; to do so without finishing his decompression would be
certain death. He can only wait, locked into the silence of a diver underwater,
suspended in decompression, mourning his friend.
“That
was a horrible moment,” remembers Bowden. “We knew the risks we were taking, but
still, it was hard to imagine Sheck not surviving the dive – not surviving any
dive.”
Within
hours, reports of Exley’s death go out over the news wires. aquaCorps’s office
is swamped with e-mail. The rec.scuba site on the Net fills up fast, as do all
the scuba bulletin boards. The thought of Exley not returning from a cave dive
(even one to 1,080 feet) is as incomprehensible as the idea of a young Muhammad
Ali dying in the ring from a punch. “To find out that he was mortal came as
quite a shock to a lot of people,” says Gilliam.
No
one expected Exley’s body to be recovered from the depths of Zacatón – who could
go down to retrieve it? – but several days later, his descent line, heavy with
unused decompression tanks, is winched up, and his body, wrapped into it, is
recovered. An autopsy is inconclusive; with no witnesses, it’s impossible to
know what happened during the dive.
The
most likely scenario is that, like Bowden and for unknown reasons, he used up
his gas much faster than expected. Unlike Bowden, however, he mustn’t have
realized this until too late. At that point, without enough gas to inflate his
BC and rise, he wrapped himself into the line to stop his descent and to give
himself time to think.
He
was most likely experiencing flashes of narcosis as well as another episode of
high-pressure nervous syndrome. When he ran out of gas mixed for that depth, he
switched to another that could be breathed safely only much closer to the
surface. At that point, he must have suffered an oxygen convulsion, lost
consciousness, and died.
At
the ’95 tek conference in San Francisco, Exley’s ex-wife and longtime dive
partner accepts a posthumous award in his honor. Other than that, there’s little
mention of his death. Maybe the topic has been talked out. Maybe it’s time
refusing to stand still.
Dr. R.W. Bill Hamilton
The Prince of Gases
Articles | 2011/10/31 by Editor at Diver Magazine | 1 CommentRecently the diving industry lost Dr. R.W. ‘Bill’ Hamilton (1930-2011), whose intellect, compassion and love of life, will not soon be forgotten.
Text by Joel SilversteinRarely in life do we encounter someone who was as impressive yet unassuming, humble, and gracious as R.W. ‘Bill’ Hamilton, Ph.D. On September 16, 2011, Bill died surrounded by his family and close friends. Within hours, e-mails and telephone calls reached thousands of people and the news of his passing went viral. Nearly four hundred scurried to make plans to attend his memorial service. So what made this particular man so special?
Born in Midland, Texas, Bill would always explore things on the edge of the envelope. He first expanded his youthful mind with liberal arts at the University of Texas, then went on to earn a master’s degree in animal breeding at Texas A&M. He finished up his formal education by earning his doctorate degree in physiology and biophysics at the University of Minnesota. Along the way Dr. Bill joined the U.S. Air Force, earning the rank of Major and serving as a jet fighter pilot during the Korean War and again in Vietnam, where he earned the Distinguished Flying Cross, Air Medal, and other decorations.
As a Life Support Officer he helped solve equipment problems on unsuccessful bailouts, which earned him a National Academy of Sciences recommendation to NASA as a Scientist Astronaut. Eventually, Bill left the Air Force with his wife and four children and headed to Buffalo, New York, in 1964, where he met Heinz Schreiner and began his work in the undersea world.
Ocean Systems
The 1960s was a decade of change and exploration – some with art, music, politics and war protests – but for Dr. Bill, it was working as a scientist and director of a leading environmental physiology and diving research lab called Ocean Systems (a division of Union Carbide) based in Tarrytown, NY. Dr. Hamilton and his staff conducted extensive research on the effects of gases both under increased pressure and in hypobaric environments. This work led to the development of decompression modeling tools and operational procedures for divers, astronauts, hyperbaric chambers, and tunnel and caisson workers. One of the early projects, in which Dr. Bill was both the physiologist and test subject, led in 1965 to the first manned laboratory saturation ‘dive’ to the continental shelf pressure of 656 feet, 12 atmospheres (200m) of sea water. All of this was just the beginning.During his time at Ocean Systems, and after the death of his first wife Beverly in 1970, Dr. Bill met Kathryn Faulkner (aka ‘Ruby Lips’) on an Eastern Airlines Shuttle. That chance meeting turned into a 40-year marriage that has created an international family of friends and colleagues. Ruby played a pivotal role in Dr. Bill’s life, becoming a mother to his children and then grandmother to their children. Not satisfied to simply play a side role, however, Ruby also managed the business aspects of Hamilton Research, including finance, contracts, calendar, travel, and social events, and served as Bill’s sounding board for difficult decisions. It was rare Dr. Bill would be at an event without her close by.
Hamilton Research Ltd.
By 1976, Dr. Hamilton took one of the biggest risks an academic could ever take: he set out to create his own physiology consulting firm – Hamilton Research, Ltd. Tucked away in a room in his house overlooking the Hudson River, Hamilton Research became the premier organization for decompression and hyperbaric research. Dr. Bill was often sought for consultation and collaboration. He worked extensively with oil companies, the military, and others in developing procedures and techniques to mitigate the effects of High Pressure Neurological Syndrome (HPNS) while compressing to depths of 984 to 1,969 feet (300-600m).The big project from Hamilton Research that has had an inestimable impact on decompression research was the development of the Diving Computational Analysis Program (DCAP). DCAP was co-developed with David J. Kenyon, and is a comprehensive computer program that could analyze and develop decompression procedures and schedules for a wide variety of exposures to pressure, including submarine escape, space travel, deep commercial diving, caisson and tunnel work, and free-swimming technical diving. The program did nothing short of revolutionize decompression analysis. Hamilton Research, armed with DCAP, began working with British, Swedish, Japanese, Finnish, Israeli, Italian and U.S. navies; Canadian and German research centers; the Norwegian Underwater Institute, and countless other organizations around the world.
In addition to DCAP, Dr. Bill also was the principal investigator and scientist in the creation of the NOAA Repex Oxygen Exposure tables – the basis for most every oxygen exposure calculation method used today for saturation and repetitive exposures to oxygen in breathing mixtures. His work continued to evolve and was consulted by attorneys and diving equipment companies on topics including dive computers, rebreathers, and expert witness testimony. He was even consulted by food companies on packaging foods in pressurized environments. His reach was endless.
Recreational Focus
In the late 1980s, his love for the edge of the envelope was directed toward extreme recreational divers. For decades, only commercial and military divers had access to mixed gases for diving operations. But now cave divers and wreck divers wanted to go deeper and farther than air would allow them to go safely. In an unprecedented move, Dr. Bill stepped out of his traditional role with commercial and military clients and stepped into the world of sport divers. He created a custom set of decompression tables for extreme cave dives into Florida’s Wakulla system. These were dives to 328 feet (100m) on open circuit SCUBA with managed oxygen exposures and minimal nitrogen narcosis. The project was a success and now the ‘underground’ was abuzz. While some of his colleagues criticized him for these efforts, Dr. Bill believed that if he did not help these divers they would do the dives anyway and possibly get hurt. His humanity was exemplified in his desire to help them and, as such, he opened up a whole new world of underwater exploration by the free-swimming untethered diver. This was the birth of ‘technical diving.’ News of Dr. Hamilton’s tables got out and practicing deep divers from all over the world began contacting him for help.Along came Captain Billy Deans from Key West, who had been doing deep dives for years but wanted a better and safer way to do it. He and Dr. Bill became fast friends and Dr. Bill helped Billy to create the first training program for open-ocean trimix diving. The friendship played a role in the creation of the Key West Consortium—a group of divers who hired Hamilton Research, Ltd., to create a universal set of trimix decompression tables for use during open-ocean dives ranging between 180 and 250 fsw (55-76m). This opened up access to deeper wrecks the world over. The success of these tables after thousands and thousands of dives, led Dr. Hamilton to create trimix tables for NOAA for use on the USS Monitor research projects. He was also a key contributor and advisor to aquaCORPS Journal, beginning with his seminal article, Call It High-Tech Diving, in the first issue in January, 1990, which sought to explain the technological changes taking place in sport diving. This second part of an already accomplished career was shining bright.
Dr. Bill was on everyone’s invite list for conferences and workshops around the globe. He was a principal contributor to the 1992 aquaCORPS Nitrox Workshop in Houston that helped make nitrox diving mainstream in the recreational diving world. Dr. Bill then went on to write nitrox training manuals and programs for many of the certification agencies and was a major contributor to the original NOAA Diving Manual for air, nitrox, and mixed gasses. He worked with many manufacturers on their dive computers and algorithms and was a regular consultant to the U.S. Navy on matters of decompression and decompression illness treatment.
Dr. Bill was generous with his time and advice, and he served by volunteering wherever he could. Often times, this meant repairing anything, from lights in his church, to sitting on boards for the Divers Alert Network (DAN), the Undersea and Hyperbaric Medical Society (UHMS), the National Oceanic and Atmospheric Administration (NOAA), and the National Fire Protection Association (NFPA). Dr. Bill volunteered to lead conferences as a keynote speaker, and to serve in the Air National Guard. He was never more than a phone call or e-mail away to help those in need. That was his nature.
Forward Thinking
Over the years Dr. Bill was recipient of more than a hundred honors and awards from most every diving and science organization. From keynote speaker to Diver of the Year someplace in the world, he and Ruby Lips would often be featured at the party. And then, Dr. Bill would slip off for a little nap, then find a laptop or cocktail napkin, and have serious discussions with serious people about things that mattered, like life support.Dr. Hamilton’s accomplishments in life go deeper than the bottom of the sea and higher than Mount Everest. They delve into the hearts and minds of friends, family, and colleagues. He instilled the desire in each of us who knew him to be better at what we do. His contributions to the world of diving are unmatched, and his forward thinking of how divers would survive underwater is arguably the basis for all extreme exposure diving today.
His modus operandi was to get the job done right and then have a good time with the people around him. Everybody he met, if only for a moment, was a better person for it. Dr. Bill’s ability to examine and explore ways to make something or someone better was his way. A little nap here and there and he was recharged and ready to take on the next task.
Dr. Bill Hamilton was predeceased by his wife, Beverly; son, Beto; and daughter, Kitty. He is survived by his wife of nearly 40 years, Kathryn ‘Ruby Lips’, daughters Lucy and Sally, sisters Emily and Ann, grandsons, Felix, Bobby, Zach, Tyler, and Truman, and an untold number of adoring and loving fans. He is already missed.
Dr. Hamilton’s resume and many papers can be found at http://rubicon-foundation.org/hamilton
Joel Silverstein was co-author with Dr. Hamilton on a number of books, programs, chapters, and other projects, and was proud to call him a dear friend. Contact: joel@joelsilverstein.com
Remembering Bill
It’s 1966 in Buffalo, New York, and I’m inside a steel-walled chamber at the Ocean Systems research facility—decompressing from a dive to 650 feet (200m). I have a fierce pain in both knees and it’s growing into a fire that makes me dizzy. Something’s gone terribly wrong with our experimental decompression schedule and tiny oxy-helium bubbles are turning sharp knives inside my body.I notice a handsome, reassuring face in the viewport talking to me on the intercom: “Don’t worry Doc, we’ll recompress you to a depth that will compress the bubbles. Then we’ll reconfigure the decompression schedule to bring you up safely.” It Is my brother-in-science Bill Hamilton—jet fighter pilot and diving physiologist, a man as comfortable flying at the speed of sound as he Is measuring the respiration of divers breathing helium deep beneath the ocean.
Bill was blessed with high bandwidth intelligence and emotional empathy—a man who listened closely to what you said, waited until you finished and never dropped eye contact. He had equal measures of cool competence, physical robustness and mental resilience. As a senior member of our research team he was occasionally blunt; when he felt the need he would attack a comment or a question with a surgeon’s precision. But if there was a problem, he was the first one to step up and say, “We can solve this.”
Bill was one of those daring men who explored the physiological limits of the human body. He had a unique way of choreographing scientific data and the facts within the data and the relevance of the facts—weaving everything together into an observation or report that enhanced the health and safety of working divers at extreme depths.
Bill, his partners, and a room-sized IBM 360 computer quickly came up with a recompression-decompression profile that allowed me to stumble out of the chamber 10 hours later with knees bruised but intact. That night we took the team to a five-star restaurant in Niagara Falls and went mano-a-mano with three bottles of rum. Honest, humorous and courageous, Bill Hamilton was someone you could count on when water was pouring into the ship.
Dr. Joe MacInnis
Contributions ‘Immeasurable’
Bill did not just mentor me, he forever changed my future – and in many ways saved my life by pushing me to be exceptional by his example. He saved me from accepting my present, and dreaming my future into reality. We enjoyed 40 years of doing the impossible together, all with lots of love and good laughs.Glenn Butler, CEO
Life Support Technologies
Dr. Hamilton’s contributions to the world of diving were immeasurable. We are eternally grateful that he devoted his life to keeping others alive while they were visiting alien environments. His generosity of spirit is unmatched in our fields.
Capt. Kathy A. Weydig, Co-Founder
Women Divers Hall of Fame
When I asked him which approach to decompression is the best idea or theory his response represents his sense of humor in the best of ways. His response, “It is better to do something, than not.”
Grant W. Graves
U.S. Apnea Association
Bill contributed so much to the world of diving: his proprietary DCAP decompression tables, the concept of Oxygen Tolerance Units, research and insights into various aspects of hypobaric and hyperbaric physiology… to name a few. He was a humble guy who always enjoyed sharing his love of, and curiosity about, life, including his cooking, his gardening, his favorite mixed drink recipes, and various insights into the world.
Bernie Chowdhury, Author
Dr. Hamilton was a major motivator in my career as well as one of the earliest supporters of Rubicon. He was always checking in to see what else he could help me find or to make sure I knew who to talk to about permission for rare documents.
Gene Hobbs, Founder
Rubicon Foundation
Though most sport divers today have probably never heard of him, Dr. Bill Hamilton‚s involvement was critical to the development of tech diving, and the adoption of mix technology by the sport diving community. His contribution was much more than just providing decompression tables. Rather, Dr. Bill provided the knowledge, needed experience and judgement that helped nourish and guide the emerging tech community.
Michael Menduno, Founder and Editor
aquaCORPS Journal
26 Mart 2012 Pazartesi
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