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Steve
I have one comming to evaluate here in the USA. I think if you convert the
dollars/pounds it is a little over 3,000.00 but still less than 4 and I was
really impressed with the unit. It is the most simle design with good backup
that I have seen in a unit that is not a 15k plus dollar figure.
I think with these units(phoneix {UK one referenced}, prism, and Biomarine
ccr500) and the soon to be released semi closed passive system by
brownies(odessey) that these particular units will control the market.
Tom
At 12:19 PM 6/26/96 +0000, you wrote:
>Well I've now got the OK to put this posting up onto techdiver. Seems like
with
>the Biomarine $5k unit, this one for $3k and the Cochran/Prism unit for
$5k, the
>affordable closed circuit rebreather market is finally becoming a reality.
>
>I've got some pictures of the 'Inspiration' rebreather, taken at the UK IANTD
>weekend. I'll scan them in over the next 2 days & send them to Eric Lundquist
><ericl@oc*.wa*.ed*> to put up onto his web page
>(http://diver.ocean.washington.edu/rebreather.html)
>
>Hassle Eric, not me, if you don't get to see them next week or so (sorry
>Eric..!)
>
>
>*****************************************************************************
>Launch of A.P.Valves "Inspiration" Closed Circuit Rebreather
>
>The IANTD annual conference in Swindon, UK saw the launch of a new closed
>circuit mixed gas rebreather that is expected to retail for two thousand
pounds
>(ie approx $3000).
>
>
> The rebreather has been developed by Dave Thompson, Pheonix Diving Ltd in
>conjunction with A.P.Valves over the past 3 years and is planned to be
available
>to suitably trained divers by November 1996. A.P.Valves are the British
>company well known for their manufacture of the "Buddy" range of buoyancy
>compensators.
>
>All training will only be conducted under IANTD guidelines. A sequence of 3
>courses, totalling around 10-12 days in total are needed before the unit
can be
>used for mixed gas decompression diving. The courses are :
>
>IANTD Rebreather Module I - No stop Nitrox rebreather diving
>Prerequisite = IANTD Advanced Nitrox Diver.
>Course = 3 to 4 days
>
>IANTD Rebreather Module II - Decompression Nitrox rebreather diving
>Prerequisite = IANTD Technical Nitrox Diver.
>Course = 3 days
>
>IANTD Rebreather Module III - Decompression Trimix rebreather diving
>Prerequisite = IANTD Trimix Diver
>Course = 4 to 5 days
>
>I would expect that the total cost of all 3 courses would amount to just under
>1000 pounds ($1500).
>
>The unit itself comprises a harness and back plate + cover, housing two 3
litre
>cylinders and a cylindrical scrubber unit. Wrapping over the shoulders and
>extending around the front is a split inhalation/exhalation counterlung. The
>rebreather as seen at Swindon had an integrated A.P.Valves 'wings' buoyancy
>compensator that I understand is not to be included in the price of the
system.
> However, any Dive-Rite or OMS wings already owned by the prospective
purchaser
>will bolt directly onto the rebreather.
>
>The rebreather is a fully closed unit capable of being used with Nitrox or
>Trimix as a diluent and has a maximum expected operating depth of around 100
>metres. I guess the max depth limit will depend upon things like warmth,
>open circuit bailout, acceptable deco time & so on, rather than any
function of
>the operation of the rebreather itself.
>
>Although the rebreather contains electronics and processing capability
>to control the partial pressure of the breathing mix, there is at present no
>decompression capability. All decompression must be worked out in advance and
>tabulated using the "Proplanner" decompression software or any other software
>capable of handing constant ppO2.
>
>Alternatively, for nitrox use a standard constant FO2 nitrox computer can be
>used. This is done by setting the nitrox mix on the computer for a ppO2 of
1.3
>for the maximum intended depth. At any shallower depth the actual mix in the
>counterlung will be more oxygen-rich than the dive computer thinks it is,
giving
>an additional factor of safety. The deco using a dive computer in this way
may
>end up being either longer or shorter than using square profile tables, but it
>does give a greater underwater flexibility. Clearly, this option is not
>presently available for trimix...no one yet sells a trimix open cicuit dive
>computer.
>
>The unit displayed and demonstrated at Swindon held two gas cylinders - one
for
>oxygen and one for the diluent, either air or Trimix. If advantage is to be
>taken of the counter-diffusion benefits of using Nitrox for decompression
>following a Trimix dive then it would be a relatively simple matter to
manifold
>an addition diluent cylinder to enable this gas switch. This facility wasn't
>actually on the unit I saw at Swindon, so I'm limiting my description to
what I
>actually saw rather than what might be done on some future unit.
>
>At present the "Inspiration" rebreather has an automatic injection of oxygen,
>controlled by 3 oxygen sensors and a 'voting logic' system. Diluent is
manually
>injected by the diver as the counterlung collapses with increasing depth. The
>oxygen partial pressure set-point is selected by the diver at either 0.75 or
>1.3. It is intended that a set point of 0.75 would be used at the start of
the
>dive until the diver has reached the bottom. The set-point would then be
>switched to 1.3 for the remainder of the dive, until the diver came back up
to 3
>metres, when it would be switched back to 0.75 to prevent unnecessary
injection
>& waste of oxygen. A 1 hour dive typically used about 20 bar of both
oxygen and
>diluent. Both cylinders can be filled to 232 bar.
>
>Both the inhalation and exhalation hoses pass over the shoulders to the
>mouthpiece via water traps that will discharge any water accidentally entering
>the hoses into the counterlungs, where it can be vented back out of the
system.
> The mouthpiece has a simple open-close facility by rotating the body of the
>mouthpiece against the gumshield.
>
>The carbon dioxide scrubber stack is mounted between the two cylinders and
holds
>sufficient sodium hydroxide ("Sofnolime") for 6 hours of diving. The
>accumulated diving hours between scrubber renewal is logged automatically
by the
>control unit and a warning is given when the scrubber needs renewing. A
>hydrophobic membrane is used to repel any water that manages to get past the
>water traps and enters the scrubber unit.
>
>I had a brief opportunity to try the "Inspiration" rebreather in the hotel
pool
>at the Swindon weekend. My initial impressions were very favourable. The
unit
>is very comfortable to wear and fits on with conventional adjustable shoulder
>straps, a cummerbund waist strap and a chest cross strap Mechanical contents
>pressure gauges for both cylinders were located comfortably around the waist
>region , alongside the primary partial pressure display unit. The entire
>rebreather weighed less than my lightweight steel twin 12 litre cylinders.
The
>mouthpiece feels less cumbersome than it looks and the buoyancy of the
inlet and
>exhaust hoses is counterbalanced by two brass rings. Breathing underwater is
>predictably easy, but unlike some other rebreathers I have tried, the
breathing
>resistance does not vary with diver orientation. I tried lying on my back,
>standing inverted and swimming on both sides. The light breathing resistance
>remained constant.
>
>Initially, I was too buoyant. Exhaling through my nose to dump some gas
>resulted in my having insufficient gas in the counterlung to breath
comfortably.
> The addition of two leadshot weightbags to special compartments built into
the
>unit solved this problem and the rest of the trial experience was a pleasure.
>
>
>So...when can we all buy one ?? Well the last hurdle to be overcome is
to get
>EEC certification for life support systems, which involves assessment by an
>independent authority. This is not expected to be a real hurdle. The unit
has
>to conform in breathing resistance at the intended depth and also has to
exceed
>certain scrubber breakthrough criterea. On both counts the unit exceeds the
>performance of the Drager Atlantis rebreather, which passed both tests
easily.
>Assuming all goes well then an initial batch of 50 units are to be
manufactured
>and are expected to be available by November 1996.
>
>At present A.P.Valves are NOT interested in taking deposits or names and
>addresses until they have a rebreather to sell. Please don't waste your time
>and theirs by hassling them and pleading that you are a special case !! Wait
>until November 1996 and THEN contact them and get your name & deposit down.
We
>all know the bad press that companies like Biomarine & Cis-Lunar are
getting for
>not answering mail from prospective or actual customers. I wouldn't like the
>same word to be spread around from a responsible UK company like
A.P.Valves. So
>don't, I repeat *DON'T* hassle them until November. After all the time we
have
>been waiting for a sensible and affordable rebreather to come...November isn't
>so long to wait, is it ?
>
>
> 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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