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The following is a personal report on Talks, Workshops and Trade Exhibitions
seen at the IANTD UK Conference this weekend. I will try & present a synopsis
of what I heard & saw. If you disagree with any of the content or views
presented then by all means post your alternative views but please don't flame
me. I am simply recording what was seen & said and make no comment here on any
statements made by others.
I have taken a number of photographs from the conference of items such as the
AP
Valves Inspiration & Cis-Lunar Mk.5 rebreathers. I can scan these pictures in
to my computer but as yet I haven't gotten around to making up a web page for
myself. If anyone is willing to put a few of these pictures up on their own
web
page so that anyone can view them then please let me know.
SUNDAY APRIL 27TH
********************************************************************************
BILL STONE CIS-LUNAR MK.5
For his 2nd formal presentation Bill Stone began by announcing WAKULLA 2 -
Oct.
1 1997 to Jan 30 1998. The U S Deep Cave Team (USDCT) is looking for divers to
assist with this expedition with a range of skill levels, including rebreather
diver, support diver, programmers and chamber operators.
An overview was first given of the Wakulla Springs cave and the 1987 WAKULLA 1
expedition. The development of a decompression habitat was reviewed which
would
enable up to 6 divers to decompress for 10 to 15 hours in warm dry conditions
from depths between 70' and the surface. Some of the early sport dives in the
USA using mixed gases were shown where divers wore 4 or 5 tanks on their body
and had a further 4 to 5 tanks strapped to their scooters. A short 3 minute
video clip was shown of Rob Parker, Wes Skyles and Brad Solomon penetrating
Wakulla against a 1+1/2 knot current & returning to the habitat.
Bill then spent some time reviewing the theory of failure analysis and
reliability as applied to existing closed circuit systems (USN Mk15 & Mk16),
independent quad tanks, manifolded twin tanks and redundant closed circuit
systems (the Cis-Lunar Mk.1 to Mk.5).
An overview of the principal features of the Mk.5 was then given (for those who
missed the workshop). Additional features which were covered were :
Head up display
Deco LED - has 3 states.Green = no problem,
Flashing green = deco stop reached,
Red = too shallow
Oxygen LED - has 5 states Green = OK
Yellow = too high ppO2
Flashing yellow = too low ppO2
Red = above 1.6 ppO2
Flashing red = hypoxic within 5 mins
System LED has 2 states Green = OK
Red = Check primary display to
identify
system problem
The Mk.5 is said to have a 6 hour capability at any depth for a typical diver
swimming at 20m/min. At rest a duration of 10 hours would be expected. It has
a weight of 55 lb. and a volume less than twin 80s. It can be fully integrated
with a Morgan full face mask incorporating comms. The gas efficiency against
an
open circuit set is typically 56:1. On board cylinders were 400 cu.ft
(oxygen)and 240 cu.ft.(diluent) in size. The total number of hours spent of
Cis-Lunar rebreathers is in excess of 2500 hours.
Bill discussed the original plans to include a CO2 sensor & alarm feature &
concluded that with existing technology it was not possible to include an
effective CO2 detection capability into the Mk.5 and that this feature had
therefore been dropped. The Mk.5 does however not only record the total time
spent using the scrubber since it was last refreshed, it calculates the CO2
that
should have been produced from the O2 consumption (assuming no gas loss through
leakage, mask clearing etc.) and incorporates a warning if the scrubber is
reaching the limit of its expected duration.
The final part of the talk focused on the plans for 'Wakulla 2', Bill Stone's
next planned expedition into Wakulla Springs cave system some 10 years after
the
original 'Wakulla 1' expedition.
No mention was made of the on-going Woodville Karst Plains Project (WKPP)
explorations over the past 10 years, headed by George Irvine and his team of
lead divers & support crew. WKPP are presently exploring Wakulla Springs using
radically different techniques, philosophy and rebreather to that proposed by
Bill Stone.
The Wakulla 2 expedition is expected to cost around 1.3 million $US with the
funding all coming from private sponsors. The stated objectives are :
To explore up to 6 km from the entrance,
To produce a 3D map of the cave system, integrated to surface features
with an accuracy of 5cm
To leave no impact on the park at the end of the expedition
The expedition has developed DPVs (scooters) with a 15 km range which are about
2 x the size of an Aquazepp. The DPVs use NiMH batteries and the diver will
effectively be diving with 3 Mk.5 rebreathers (one on their back and 2 attached
to the DPV), giving a possible 18 hour capability. No staging of open circuit
tanks is planned. One type of DPV incorporates a backup DPV with a 6 km range.
Another model incorporates an automated digital wall mapper in the DPV nose.
The mapping system works by using some 64 sonar sensors arrayed in a helical
pattern around the nose linked to a 3D inertial guidance system which
automatically gives the x,y,z position co-ordinates of the DPV together with
the
pitch, roll and yaw aspects. Scanning position data at a rate of 50 times a
second, the entire tunnel cross-section will be automatically mapped to a 5 cm
accuracy. As a backup to correct some known drift problems associated with
inertial guidance systems (at worst a drift of 1m in 200m-300m might occur), a
sequence of 'drop pods' with flashing LED's will be positioned at regular
intervals along the tunnel system. The light from the LED's will automatically
be detected by the DPV system & any inertial drift corrected. Up to 8 Gb of
data
can be stored by each DPV.
The expedition divers are not planning to carry out their dives as in previous
'bounce dives' excursions from the surface with in-water or habitat
decompression at the end of each dive. Instead it is planned that lead divers
4
of 2x2 man teams will remain in saturation in a surface hyperbaric habitat
maintained at a pressure of 55m-65m. The habitat weighs some 100,000 lb. and
will be transported into the entrance region in sections. The habitat will be
located on a floating barge and divers will be transferred to a depth of 55m in
a transfer bell.
One of the principal planned objectives of the expedition is to produce a
virtual environment theatre so that the public can experience what it is like
to
explore Wakulla Springs. Visitors will wear 'crystal eyes' LCD shutter glasses
and will be able to experience a full 3D virtual reality show. In addition the
3D map will be available for scientific aquifer studies to enable tracking of
pollutants through the cave system to be modelled. In fact Bill stated that
although he hoped that the known limits of the Wakulla Springs system would be
significantly extended, even if no new cave were actually reached but the 3D
mapping system worked as planned on the existing known cave then the whole
expedition would be considered a 100% success.
The talk concluded with a short computer animation showing a visualisation of
the cave system explored in the original 1987 Wakulla 1 expedition. A 3D model
was shown which could be rotated, panned and zoomed to display features of the
cave system. The Wakulla 2 expedition was expected to involve between 75-100
people for periods of 2 weeks or more and an invitation was extended for those
interested to contact the project.
********************************************************************************
WORKSHOP SESSIONS
CUSTOM DIVERS - NEW PRODUCTS
ORCA DIVE COMPUTERS
REBREATHER POOL SESSIONS
The next session comprised 3 parallel sessions as listed above. I attended the
pool session and was fortunate to be able to try both the AP Valves Inspiration
and the Cis-Lunar Mk.5 rebreathers, one immediately after the other. Both
units
felt very compact and comfortable underwater but a direct comparison would be
unfair on both units, which are each aimed at entirely different diver markets.
The following comments represent my personal opinions from these practical
'hands-on' sessions.
The Mk.5 is a very complex unit and during such a short tryout session there
was
a lot to take in and appreciate. The automatic injection of both diluent and
oxygen led to effortless operation. Each time I tried to upset the Mk.5 by
manually adding an excess of diluent or oxygen to make the ppO2 deviate from
the
setpoint then the unit smoothly came into action and corrected the ppO2 back to
the required level. The flashing red LED in the head up display certainly got
my attention when I forced the ppO2 to deviate from the 0.7 setpoint down to
0.21 by flushing the counterlung with diluent (air). The primary display
certainly contained a lot of information in the 'small font' display mode, but
the most important information (ppO2 & deco details) was quite large & clear.
The cylinder pressures of both oxygen and diluent was displayed quite cleverly
in both digital and analogue mode. From a first look the display appeared
quite
complex, with a lot of information to take in. However I'm sure that with
training and experience a quick glance would be all that is needed to assess
the
rebreather & dive parameters. The reverse side of the display unit showed the
secondary ppO2 sensor display. This comprised three columns of LED's going
from
0.2 to 2.0 (I think). The ppO2 of each sensor was lit up by the appropriate
LED
and was extremely clear to read.
The split counterlung of the Mk.5 gave a very easy breathing resistance which
did not vary as I rolled onto my side or back or went inverted. The combined
open/closed circuit mouthpiece was very light and comfortable and represented a
significant improvement from the Mk.4 that I had tried out a couple of years
ago. A switch from closed to open circuit proved to be quite a simple
operation.
One feature that I personally didn't like very much was the armoured impact
guards that protected the breathing hoses and water traps from accidental
damage. Although these guards looked very solid & strong, the attachment
brackets appeared very flimsy and looked like they might bend or break with
very
little effort. However, for such an impressive unit this is a very small
criticism to make.
For such a complex unit I would also be somewhat concerned about what I would
be
able to do to fix it if anything went wrong and what sort of speedy support I
could expect in England to remedy any problems that might arise. When
Cis-Lunar
develop a sales, training and support facility on this side of the Atlantic
then
the Mk.5 might then become a much more attractive proposition for those divers
who can afford the $15,000 price tag and have the operational needs to justify
this expense.
The Inspiration on the other hand had much less to look at and distract me. To
be fair to the Mk.5, I had already been on a 4-day training course for the
Inspiration earlier this year and so all the controls and displays were
familiar
to me. The unit has the same split counterlung configuration as the Mk.5 and
proved to have an equally low breathing resistance. It may have been my
imagination, but I think that the Inspiration may have been marginally easier
to
breath from...but both units were excellent and a comparison is probably just
'nit-picking'. The diluent on the unit has to be manually added when the
counterlung volume becomes too small but this is easy to do and soon becomes as
automatic as feeding air into the buoyancy compensator when necessary.
I think that Cis-Lunar has a USA patent on the concept of a split counterlung
positioned over the shoulders & if so it is unlikely that the Inspiration will
ever be sold by AP Valves in the USA. The Biomarine CCR500 rebreather would
appear to be the closest unit to the Inspiration available in the USA.
The production version of the Inspiration has several changes new to me. The
unit now has two independent computer control/display units. Whichever one is
turned on first becomes the 'master' unit & drives the rebreather. The other
unit is a 'slave' unit & simply provides a passive display of the ppO2 sensors,
scrubber lifetime etc. However, if the master unit is then turned off then the
slave unit takes control and transforms itself into the master unit..
The Inspiration now has an audible alarm warning if the ppO2 deviates too much
from the set point. This wasn't as loud as I would have liked, but I didn't
have the opportunity to hear it underwater I so I cannot say if it really would
grab my attention as it should. It is also now possible to alter the two
surface and bottom setpoints to any chosen value (the prototypes I had seen
earlier simply used 0.75 and 1.4 ). The display unit now also displays the
total time used on the CO2 scrubber.
A small modification that I immediately noticed is that the top of the
Inspiration cover plate is chamfered at 45 degrees over 1.2 of its depth. This
provides a significant streamlining effect which I noticed when I swam hard for
2 lengths of the pool (it was a small pool ..!!)
With a price tag of 2000 UK pounds ($3000), the Inspiration is aimed at the
more
normal technical diver with a firm grip on the financial realities of life
********************************************************************************
TEKKING IN THE PHILIPPINES ALEX SANTOS
Following the practical sessions, a 1 hour presentation was given by Alex
Santos
on the diving opportunities available to technical divers wishing to visit the
Philippine Islands. With typical water temperatures of 26 to 30 degrees
Celsius
at depths of 60m to 100m, hypothermia is not going to be the normal problem
that
many technical divers are used to...! Three sorts of dives were presented by
Alex, i.e. deep sea diving, wreck diving and cave diving (both inland limestone
solution caves and larva tube sea caves).
The wrecks that are discovered include galleon sites from the 16th century,
many
with cargoes of Chinese silks, porcelain and gold (!), and WW2 war wrecks. Two
of the galleons described were the 'San Diego' located in 55m off Fortune
Island
and the 'Panadanan wreck', an unknown Chinese junk with a cargo of porcelain.
Both wrecks have been well salvaged by a team of French divers and the
artefacts
are now in a museum in Paris. However there are many more suspected galleon
wrecks that would have made for the Port of Galera in a storm, but would have
not made the safe haven in time. Of the WW2 wrecks, over 100 lie in Lingayen
Gulf which at 200m to 1200m is beyond the reach of today's technical divers.
However there are 12 Japanese WW2 wrecks, of which 8 have been found, in Caron
Bay. These lie at depths between 10 and 42 metres and are all pretty much
intact. Artefacts recently discovered on these wrecks include a complete 30's
car with white walled tyres.
Diving in the Philippines can be done all year round but the typhoon season
(July-October) holds the greatest risk of being weathered out. Technical dive
gear is available for rent together with both Nitrox & Trimix. 4 recompression
chambers are located on the Philippines, but in-water recompression is normally
used as a first resort if decompression problems occur.
In addition to the sea diving, Alex reviewed some of the cave diving potential
in the Philippines. There are presently just 4 active cave divers on the
islands willing to assist with expeditions.
Cave sites include :
Palavan Caves /Barracuda Lake Cave - an inland
limestone cave that has been explored to 30-40m depth. this cave must connect
through to the sea, due to the existence of marine sea life found in the cave.
Batangas Caves / Mapating Cave - a larva tube cave with the
entrance in the open sea. This cave has been partially explored in the 45 to
60
m depth and contains coral growth, luminous Flashlight Fish and giant stingrays
with wingspans of up to 6 feet.
Cagayan Caves / Jun's Promise - a well decorated
limestone cave in the northern jungle region, accessed using '4 x 4' transport.
In this part of the world 4 x 4 refers to oxen & sled transport...!
Contact Alex Santos by email at philtech@tr*.co*.ph* for more information.
********************************************************************************
FRENCH CAVE / TECHNICAL DIVING JEAN-PIERRE IMBERT
This talk focused on technical diving from a French perspective. A review of
some developments in French cave diving was given and some excellent shots of
prehistoric art in caves near Marseilles found by Frech cave dives included a
picture of a penguin that must once have lived nearby (?)
Some of the skills of professional diving with Comex were applied to caves
calles 'Les Etapes'. One diver went down to a depth of 100m on an umbilical
line and then switched to open circuit to push to 120m. However the experience
was not reported to be a pleasant one. The following push was done entirely on
an umbilical line with surface supplied gas and a depth of 155m was reached.
However the support team & resources for this style of diving was tremendous &
was shown the way shortly afterwards when a German cave diver (Hasenmayer ?)
supported only by his wife went to 220m using just open circuit equipment.
Thje talk then focused on the 'Port Miou' cave pushed in 1993. Mining
equipment
was used to drill a vertical shaft some 30m to ease access problems to the main
cave system. A horizontal dive at a depth of 35m for a length of 1.5 km was
followed by a vertical shaft that was dived to a depth of 147m. Extensive use
of Aquazepps were used for this expedition.
A third cave saga was recounted at the 'Fontainne Vacluse' site. This diving
again made high use of the existing technology, including the availability of a
1-man decompression chamber to be used as a 'hyperbaric stretcher' if required,
and a decompression habitat that could be moved between 12m and 6m. Use was
also made of a tethered remotely operated vehicle (ROV) for exploration.
Unfortunately the 1st ROV became entangled in existing line & became stuck. A
2nd ROV with a cutting disk at the nose was sent in to rescue the 1st ROV.
This
also became entangled & stuck...! Two divers were then sent in to a depth of
165m & managed to rescue one of the ROVs. This ROVwas then sent back in to
recover the 1st ROV but it got stuck again !! Eventually both ROVs were
recovered & a lesson was learned......
Jean-Pierre then reported on a new spirit emerging in the French cave diving
scene of cooperation with cave divers working together with less secrecy and
greater efficiency. Some recent developments included :
- Development of P-valves to replace the use of diapers on long cold
decompressions
- Use of Argon to improve thermal efficiency of drysuits
- Development of electrically heated suits. These had many problems
with connection & cable failures but was eventually solved by using 12V
electric
blankets used to keep car engines warm overnight in winter.
- Use of drinks and food in the water during decompression.
- Development of a new regulator, the Connex 'Tekstar'. This is rated
to 360m and is replacing the Posiedon as the technical diver's choice.
Finally, Jean-Pierre reviewed decompression theory & stated that the
traditional
'Compartment Tissue Theory' seems to break down for dives in excess of 120m.
Few tables are reliable at depths below this and many bends within existing
tables are being experienced. Some dives are being conducted by the French
Navy
in the 160m - 170m range. The problem seems to be 'vestibular hits' caused by
microbubbles & resulting in nausea & vertigo during the ascent period. The
solution is to slow down the deep ascent part of the dive and to include a
mid-depth deep stop of 5-10mins. This is in agreement with the personal
findings of Rich Pyle in Hawaii, who recommends a deep stop of a few minutes,
even where the conventional tables do not indicate that this is necessary.
Jean-Pierre then outlined a new method of tracking dive profiles by plotting
the
logarithm of the stop times against depth to produce a smooth curve, that
resulted in slower ascents during the deeper part of the ascent and deep stops.
Ther are currently 4 French working below 150m and the details of their
respective current projects was reviewed. Olivier Isler had planned a dive to
165m some 2 weeks ago using two semi-closed rebreathers but was stopped by
technical problems on the surface. Another push is planned in 2 weeks time &
he
may eventually exceed the 200m limit.
********************************************************************************
WORKSHOP SESSIONS
AP VALVES / BUDDY 'INSPIRATION'
SCOOTERS
Two parallel workshop sessions were held & I attended the one on Scooters held
by Dave Wilkins and Alan Wright. Two scooters were available for inspection,
i.e. an Aquazepp LS1224 and an AUL Predator 2000.
The 1st point made by Dave was that the talks were centred on wreck diving from
hardboats in the UK in rough seas, conditions very different from the warm
clear
waters of Florida caves. Hence equipment weighing over 100 lbs that might be
suitable in some sites in the USA would be entirely unsuitable for the sort of
diving & conditions over here. Getting the sccoter in & out of the water was
the principal problem. You have to be able to carry the scooter as well as
quad
steel cylinders to the edge of the boat & jump unaided into the sea. A 50 lb
scooter was the maximum practical weight.
BENEFITS
Speed - Approx 5 times as fast as finning with quad cylinders. The
sccoter is used principally to gain access to the dive site. For a typical 20
min bottom time, 2 mins may typically used to get to & from the shotline to the
required site. The scooter is then not used again until the return 2 mins.
However the same dive done with finning would spend 10 mins getting to the site
& then spend 10 mins getting back again. Hence total time spent on the site =
16 mins (scooter) vs 0 mins (finning). A more efficient use of bottom time.
Range - For undived sites a quick overview can be made by scootering
over the entire wreck. Excursions off the wreck site for artifacts can be
made.
More effective searches can be made.
Towing - Moving the hardboat grapnel to the wreck (if missed) or to a
better part of the wreck is possible
Gas consumption - This is reduced to around 50% of the gas used by
finning.
DRAWBACKS
Getting lost
Task loading
Solo diving
Stranding - from scooter failure or getting lost. The diver must be
prepared to ascend off the shotline. Staging of cylinder is not possible. The
dive boat must not be anchored.
Bad vis / Rough weather - 5m vis is a minimum. Rough seas make entry &
recovery difficult
High cost
RIGGING + MODS
Ropes - Holding : A thick rope is needed on the boat to
recover the scooter (a 2 man operation).
A secure, foolproof clip is needed.
Tethering : A rope is needed to hang the scooter from
the shoulder D-ring to allow entry into
the water
Towing : A short rope to clip to the wings scooter
ring is needed
Trimming - Rubber inner tube is needed to prevent excessive
scuffing of the scooter body
Reinforcement - The Predator 2000 has a weak fibreglass tail
around the prop. This must be reinforced with a brass
or aluminium tail ring to allow the scooter to be stored
upright without eventual damage
REVIEW OF SCOOTER MODELS
American Underwater Lighting : Predator 2000. AUL are a small USA
firm who reportedly show a pretty 'laid-back' approach to sales outside the
USA.
The 2000 range scooters have two 12V lead-acid batteries with approx 1 hour
duration. All the fitting holes go right through the scooter body, with
associated potential leakage problems (invest in lots of bath sealant was the
recommendation given ! ). The quoted depth rating is 1000 feet. The 3000
range has 3 12V batteries. The 4000 range has 4 12V batteries but both units
are said to be too bulky & heavy for wreck diving in the UK. Each additional
battery unit costs $500, is 10" long and weighs about 25 lb. Cost of the 2000
=
approx $2500. This works out at about 2800 UK pounds with shipping & taxes
included. The Predator 2000 has speed cotrolled by a variable rheostat but has
no 'dead man's handle'. Some problems with leakage down the propshaft gland
reported. The main bearing had to be replaced but this could not be done by
the
owner. Cost of shipping back to USA for repair = 300 - 400 UK pounds
Farallon : Made & sold a lot of scooters but then went bust, leaving
its customers without support.
Apollo : A small plastic scooter, but looks well engineered. Cost
between 700 - 1300 UK pounds. Ocean Leasure are importers to the UK. Max
depth
rating is 50m. One unit was taken to 70m & came back OK. Another looked very
stressed at 75m but survived the experience (!). Not a very powerful scooter &
does not work well with quad cylinders. The prop wash comes out adjacent to
the
sidemounted cylinders, severely limiting the power.
Mako : Similar to Apollo. Imported by Oceanic (?). Cost 1000 UK
pounds (?)
Torpedo : Small, delicate, fibreglass.
Aquazepp : Costs 1700 UK pounds. Switchable from 12V to 24V. 2
speeds for each voltage gives 4 speeds in total. The model seen had lead-acid
batteries. NiCd and NiMH batteries now available. The duration of the model
seen was 4+1/2 hours on speed #1, 3 +1/2 hours on #2, 100 mins on #3, 45
mins
on #4. The nose light was 250 watts at 24V but would reduce the duration by
about 10%. The Aquazepp is depth rated to 95m, but can be upgraded to 200m.
This scooter looked more rubust than the Predator. The propguard was sturdy &
all holes drilled into the scooter body were 'blind' holes & hence couldn't
cause leakage problems.
(Neither of the speakers seemed to know anything about the first class scooters
made & sold by WKPP in Florida. A pity ! One member of the audience suggestd
that a price of around $3500 would be about right but that availability &
delivery times could be a problem)
********************************************************************************
TECHNICAL EXPEDITIONS BERNIE CHOWDHURY
The final talk of the conference was given by Bernie Chowdhury, editor of
Immersed magazine. The talk concentrated on the planning stages needed to
organize two expeditions : the 1991 Andria Doria Expedition and a more recent
Icelandic Cave Dive Expedition.
For both expeditions bernie emphasized the importance of the expedition leader
to go himself and carry out a reconaissance of the dive site before planning an
expedition involving others.
A reconnaisance of the Andria Doria was carried out by Bernie in 1990 and was
novel in bringing traditional cave diving techniques to a wreck diving
environment. The Andria Doria expedition in 1991 was the first trip to the
Andrea Doria where the use of mixed gas was included in the planning. Some
divers, such as Billy Deans, brought their own mixed gases. Others such as
Bernie himself chose to dive on air.
A reconnaisance to Iceland was carried out to assess the potential of two caves
formed by tektonic plate movement. Typical water temperatures were 3 degrees
Celsius and hypothermia was a real problem impossible to avoid.
The 'Karlaga is locatated in Thingvellir National Park and is subject to
constant geological activity within the timespan of a few years rather than
1000s of years. A solo dive was conducted to see if an expedition would be
worth organising. The dive pushed forward the 'end of the line' by 50m and
managed to recover an exploration reel left my the previous team there.
In the Silfur Hellir Rift a cave was explored to a depth of 59m using air. 3
restrictions were passed but problems of both cold and narcosis were
experienced. The final restriction at 59m proved to be too tight for a diver
wearing back mounted cylinder. In the next expedition side mount or 'no
mount'
cylinders would be preferable.
In Iceland one can now buy Nitrox, Trimix and Argon over the counter. For the
next expedition, use will be made of the skills of one German team member. He
has already designed & built a portable 2-man decompression habitat and has
also
designed & built his own scooter and his own semi-closed rebreather.
Bernie concluded his talk by discussing sponsorship and the use of a
professionally produced press kit to attract potential sponsors. This should
contain details of the planned expedition, contact business cards, expedition
stationary,, a list of sponsor benefits, a project overview, expedition
objectives and a build up of the team and their biographies.
A new book 'Into the field : Strategies for funding exploration' was introduced
and discusses many lessons learned on how to raise support for diving
expeditions. The book costs $50.
********************************************************************************
TRADE EXHIBITION
In between talks, workshops and pool sessions delegates found time to wander
around the trade exhibition. Some notable new items that I saw were :
A new reel designed by Kevin Gurr/Custom Divers. This was small &
compact but held 100m of line. The reel is almost impossible to get jammed &
can run free or on a ratchet for rewinding. A velcro strap handle looked very
comfortable and allowed the hand to be freed for other actions without letting
go of the reel. Cost = 130 UK pounds
A new double set of wings, again designed by Kevin Gurr and Custom
Divers. These wings looked very well thought out & very rugged. I didn't ask
the target price.
Stuart Clough's UT4000 closed circuit rebreather. No information of
this unit was given, but this was thge 1st time I had seen 'it in the flesh'.
A 'De-Nitrogenated Air' unit. This allows air from an ordinary
compressor (not oil free) to be pumped through a special membrane filtering
system and the nitrogen differentially separated off. Up to 40% Nitrox can be
obtained in this way without the need for oxygen decanting, with all the
attendant costs and risks that this entails.
********************************************************************************
CONFERENCE CLOSURE KEVIN GURR
Kevin then formally wound up the conference & wished all delegate divers a good
& safe years diving.
********************************************************************************
Regards, Steve M.
**************************************************************************
* * *
* Dr. S. G. Millard, * E-Mail : ec96@li*.ac*.uk* *
* Senior Lecturer, * *
* Department of Civil Engineering * Tel : 0151 794 5224 (UK) *
* University of Liverpool, * 44 151 794 5224 *
* PO Box 147, * (International) *
* Liverpool L69 3BX, * *
* UK. * Fax : 0151 794 5218 (UK) *
* * 44 151 794 5218 *
* * (International) *
* * *
**************************************************************************
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