4.10. Decompression algorithm
Suunto's decompression model development originates from the 1980s when Suunto
implemented Bühlmann's model based on M-values in Suunto SME. Since then research and
development has been ongoing with the help of both external and internal experts.
In the late 1990s, Suunto implemented Dr. Bruce Wienke's RGBM (Reduced Gradient Bubble
Model) to work with the earlier M-value based model. The first commercial products with the
feature were the iconic Suunto Vyper and Suunto Stinger. With these products the
improvement of diver safety was significant as they addressed a number of diving
circumstances outside the range of dissolved-gas-only models by:
•
Monitoring continuous multiday diving
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Computing closely spaced repetitive diving
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Reacting to a dive deeper than the previous dive
•
Adapting to rapid ascents which produce high microbubble (silent-bubble) build-up
•
Incorporating consistency with real physical laws for gas kinetics
The Suunto Fused™ RGBM 2 combines and improves widely respected Suunto RGBM and
Suunto Fused™ RGBM decompression models developed by Suunto together with Dr. Bruce
Wienke. (Suunto dive algorithms are a culmination of expertise and knowledge accumulated
over decades of development, testing and thousands upon thousands of dives.)
In Suunto Fused™ RGBM 2 the tissue half-times are derived from Wienke’s FullRGBM where
human body is modeled by fifteen different tissue groups. FullRGBM can utilize these
additional tissues and model the on-gassing and off-gassing more accurately. The amounts of
nitrogen and helium on-gassing and off-gassing in the tissues are calculated independently
from each other.
The Fused™ RGBM 2 supports open-circuit and closed-circuit diving up to a depth of 150
meters. Compared to previous algorithms, Fused™ RGBM 2 is less conservative on deep air
dives, allowing shorter ascent times. In addition, the algorithm no longer requires tissues to
be completely free of residual gases when calculating no-fly times, thereby reducing the
required time between your last dive and flying.
The advantage of Suunto Fused™ RGBM 2 is additional safety through its ability to adapt to a
wide variety of situations. For recreational divers it may offer slightly longer no- deco times,
depending on the chosen personal setting. For open-circuit technical divers it allows use of
gas mixes with helium - on deeper and longer dives helium based gas mixes provide shorter
ascent times. And finally, for rebreather divers the Suunto Fused™ RGBM 2 algorithm gives the
perfect tool to be used as a non-monitoring, set point dive computer.
NOTE: Suunto EON Steel software version earlier than 2.0 has Suunto Fused RGBM
algorithm. When you update the device, software will update the dive algorithm to latest
version.
NOTE: Make sure your Suunto dive computer always has the latest software with
updates and improvements. Check before every dive trip from www.suunto.com/support, if
Suunto has released a new software update to your device. When it is available, you must
install it before diving. Updates are made available to improve your user experience and are
part of Suunto´s philosophy of continuous product development and improvement.
Suunto EON Steel
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