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Tech Computers

The Scuba Doctor has a great range of quality dive computer solutions for technical and rebreather divers.

Decompression Algorithms: ZHL-16C, VPM-B, DCAP, DCIEM, VVAL-18M... Does It Really Matter?

At the risk of annoying those who do have a preference for a specific decompression algorithm, the simple answer for most divers is NO the algorithm is not critical. There is no expert consensus that any one of the current crop of decompression algorithms is better than another. All of these algorithms used in dive computers and desktop table generation software, when set to their default conservancy values, will get you out of the water with an acceptable margin of safety. What we can say for sure is they are all imperfect representations of actual decompression in humans.

Numerous variants of ZHL-16C are very widely implemented in both sport and technical dive computers. For technical diving, versions of ZHL-16C that include user configurable Gradient Factor modifications are very popular because the GF values can be 'tuned' to provide different types of profiles for specific types of diving. VPM-B dive profiles typically have deeper initial stops, along with reduced time at shallow depths resulting in a 'smoother' profile although recent research calls into question the benefits of 'deep stops' especially for lengthy VPM-B profiles. DCAP was developed for use by early extended range divers (today we call them 'technical divers'.) VVAL-18M is the basis for the modern US Navy Tables. DCIEM has been extensively tested by the Canadian military to ensure its applicability to cold water working divers. RGBM (basis for NAUI tables with its roots in VPM) and DSAT (basis for PADI tables) are most often seen in no stop required sport diving applications. Recently, the RGBM model has been called in to question by a legal action, but it's not clear if the issue is with the algorithm itself or a specific dive computers' implementation, as most experts consider the RGBM model to be very conservative especially on repetitive dives.

The practices of decompression are not exact, in many ways as much about skill as science. Much of what we do in decompression diving is based on empirical observation and experience, rather than having a basis in theoretical science. Dr. R W (Bill) Hamilton, the late co-developer of DCAP and whose research in decompression is widely acknowledged as having a key role in opening up recreational extreme exposure diving in the early 90s, was fond of the saying 'what works, works'. The most important safety factor is not the decompression algorithm you select, rather your skill as a diver and that you closely follow the recommendations of that algorithm and safe diving practices in general. Also, best practice when diving as a team is that all divers should use the same algorithm in order to remain together as a team during ascent phase of the dive plan.



Product Image Item Name- Price
Suunto EON Steel Wrist Dive Computer

Suunto EON Steel Wrist Dive Computer

The Suunto Eon Steel Wrist Dive Computer is a strongly built, wrist mounted, full colour screen personal dive computer that is suitable for all...
$1,500.00  $1,349.00
Save: $151.00 (10%)


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Suunto EON Steel Wrist Dive Computer with Tank POD

Suunto EON Steel Wrist Dive Computer with Tank POD

The Suunto EON Steel Wrist Dive Computer with USB Cable and Tank POD Multi Transmitter is the new standard for advanced/technical diving with its...
$1,750.00  $1,575.00
Save: $175.00 (10%)


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Suunto EON Core Wrist Dive Computer

Suunto EON Core Wrist Dive Computer

The Suunto EON Core Dive Computer is a compact and lightweight wrist computer with a large, bright, intuitive colour screen and mobile connectivity....
$999.00  $899.00
Save: $100.00 (10%)


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Suunto EON Core Wrist Dive Computer with Tank POD

Suunto EON Core Wrist Dive Computer with Tank POD

The Suunto EON Core Dive Computer with USB Cable and Tank POD Multi Transmitter is a compact and lightweight wrist computer with a large, bright,...
$1,249.00  $1,099.00
Save: $150.00 (12%)


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Suunto D5 Watch Dive Computer

Suunto D5 Watch Dive Computer

The new Suunto D5 Dive Computer is a watch style, colour screen, dive computer made for the active and travelling diver. The colourful screen makes...
$949.00  $899.00
Save: $50.00 (5%)


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Suunto D5 Watch Dive Computer with Tank POD

Suunto D5 Watch Dive Computer with Tank POD

The new Suunto D5 Dive Computer with Tank POD Multi Transmitter is a watch style, colour screen, dive computer made for the active and travelling...
$1,199.00  $1,139.00
Save: $60.00 (5%)


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Suunto DX Watch Dive Computer - Black Titanium Strap

Suunto DX Watch Dive Computer - Black Titanium Strap

The Suunto DX watch sized dive computer with Black Titanium Strap and USB Cable, built on the award-winning Suunto D9tx platform, is the ultimate...
$1,800.00  $1,619.00
Save: $181.00 (10%)


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Suunto DX Watch Dive Computer - Black Titanium with Transmitter

Suunto DX Watch Dive Computer - Black Titanium with Transmitter

The Suunto DX watch sized dive computer with Black Titanium Strap, USB Cable and Wireless Tank Transmitter is the ultimate tool for open circuit and...
$2,000.00  $1,799.00
Save: $201.00 (10%)


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Suunto DX Watch Dive Computer - Black Elastomer Strap

Suunto DX Watch Dive Computer - Black Elastomer Strap

The Suunto DX watch sized dive computer with Black Elastomer strap and USB cable, built on the award-winning Suunto D9tx platform, is the ultimate...
$1,500.00  $1,349.00
Save: $151.00 (10%)


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Suunto DX Watch Dive Computer - Black Elastomer with Transmitter

Suunto DX Watch Dive Computer - Black Elastomer with Transmitter

The Suunto DX watch sized dive computer with Black Elastomer strap, USB cable, and Wireless Tank Transmitter, built on the award-winning Suunto D9tx...
$1,700.00  $1,529.00
Save: $171.00 (10%)


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Featured Products - Tech Diving

Shearwater Research NERD 2 Dive Computer - DiveCAN

Shearwater Research NERD 2 Dive Computer - DiveCAN
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Shearwater Research Teric Watch Dive Computer

Shearwater Research Teric Watch Dive Computer
$1,675.00  $1,559.00
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Mares Genius Dive Computer

Mares Genius Dive Computer
$1,549.00  $1,469.00
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Garmin Descent Mk1 Watch Dive Computer

Garmin Descent Mk1 Watch Dive Computer
$1,399.00  $1,199.00
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Suunto D5 Watch Dive Computer

Suunto D5 Watch Dive Computer
$949.00  $899.00
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Garmin Descent Mk1 Titanium Watch Dive Computer

Garmin Descent Mk1 Titanium Watch Dive Computer
$2,199.00  $2,039.00
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Shearwater Research Petrel 2 OC/CC SA Trimix Dive Computer

Shearwater Research Petrel 2 OC/CC SA Trimix Dive Computer
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Shearwater Research Petrel 2 Fischer OC/CC EXT Dive Computer

Shearwater Research Petrel 2 Fischer OC/CC EXT Dive Computer
$1,840.00  $1,699.00
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Suunto EON Core Wrist Dive Computer with Tank POD

Suunto EON Core Wrist Dive Computer with Tank POD
$1,249.00  $1,099.00
Save: $150.00 (12%)

Shearwater Research Perdix AI Dive Computer

Shearwater Research Perdix AI Dive Computer
$1,440.00  $1,339.00
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Shearwater Research NERD 2 Dive Computer - Stand Alone

Shearwater Research NERD 2 Dive Computer - Stand Alone
$2,425.00  $2,255.00
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Shearwater Research Perdix Dive Computer

Shearwater Research Perdix Dive Computer
$1,299.00  $1,199.00
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