AquaExplorer
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This is apparently a selection in the certain Suunto dive computers, such as the Vyper 2.
Here is what it says:
"allows experienced divers who are willing to accept a greater level of risk to adjust the RGBM model. The default setting is 100% which gives full RGBM effect. Suunto strongly advises to use full RGBM effect. Statistically very experienced divers have less incidents with DCI. The reason for this is unknown, but it is possible that some level of physiological and or psychological accommodation can take place when you are very experienced as a diver. Thus for certain divers and diving conditions you may want to set attenuated (50%) RGBM mode."
I did some searching and found this (which is located here)
"The new generation of Suunto Diving computers, like the Vytec and the D-series wristtop computers, all employ a Suunto version of the RGBM (Reduced Gradient Bubble Model) for calculating bottom times, surface intervals, etc.
In the manual, it is possible to set the computer to what is referred to as "Attenuated (50%) RGBM". The manual does not explain what this encompasses, however, just that you get "50% of the effects of the RGBM"
Not knowing how the RGBM works, since it's a pretty complicated piece of work, and not readily available in the public domain, it's very hard to guess what they mean by that.
After writing back and forth with Suunto Helpdesk, I received this answer:
As you know Suunto computers track a number of factors in addition to how long you are underwater. When you exit the water you will notice the diver alert symbol, an exclamation point (!) inside a triangle. This means that the computer strongly recommends that you extend your surface interval until the symbol disappears. In most cases the recommended surface interval is around 45 to 75 minutes, depending on depth and time. Should you do anything "naughty" during your dive the recommended surface interval gets longer.
Naughty includes: going faster than 10m/min (getting a SLOW warning and a mandatory safety stop), reverse profile (current dive deeper than the last), decompression dives, insufficient surface interval, etc. All of these things will cause the diver alert symbol to stay on longer.
If you re-enter the water while the diver alert symbol is active the computer will penalise you and reduce your no decompression times. This is why many people think suunto computers are very conservative. The reason is that the computer thinks micro-bubbles may still be present and extra caution should be taken.
Choosing the 50% RGMB model means that the computer only applies HALF of the penalty to subsequent dives, giving you slightly longer bottom times, should happen to do something naughty (see above). Please note that in 50% RGMB mode the diver alert symbol stays on all the time as it is considered less conservative.
So there. Using the Attenuated RGBM gives you shorter surface intervals and longer bottom times on repeated dives. Why they don't put this in the manual, I don't know, but here it is. "
SO...has anyone actually dove with this RGMB model? I am curious as to how it affected the dive calculations.
Here is what it says:
"allows experienced divers who are willing to accept a greater level of risk to adjust the RGBM model. The default setting is 100% which gives full RGBM effect. Suunto strongly advises to use full RGBM effect. Statistically very experienced divers have less incidents with DCI. The reason for this is unknown, but it is possible that some level of physiological and or psychological accommodation can take place when you are very experienced as a diver. Thus for certain divers and diving conditions you may want to set attenuated (50%) RGBM mode."
I did some searching and found this (which is located here)
"The new generation of Suunto Diving computers, like the Vytec and the D-series wristtop computers, all employ a Suunto version of the RGBM (Reduced Gradient Bubble Model) for calculating bottom times, surface intervals, etc.
In the manual, it is possible to set the computer to what is referred to as "Attenuated (50%) RGBM". The manual does not explain what this encompasses, however, just that you get "50% of the effects of the RGBM"
Not knowing how the RGBM works, since it's a pretty complicated piece of work, and not readily available in the public domain, it's very hard to guess what they mean by that.
After writing back and forth with Suunto Helpdesk, I received this answer:
As you know Suunto computers track a number of factors in addition to how long you are underwater. When you exit the water you will notice the diver alert symbol, an exclamation point (!) inside a triangle. This means that the computer strongly recommends that you extend your surface interval until the symbol disappears. In most cases the recommended surface interval is around 45 to 75 minutes, depending on depth and time. Should you do anything "naughty" during your dive the recommended surface interval gets longer.
Naughty includes: going faster than 10m/min (getting a SLOW warning and a mandatory safety stop), reverse profile (current dive deeper than the last), decompression dives, insufficient surface interval, etc. All of these things will cause the diver alert symbol to stay on longer.
If you re-enter the water while the diver alert symbol is active the computer will penalise you and reduce your no decompression times. This is why many people think suunto computers are very conservative. The reason is that the computer thinks micro-bubbles may still be present and extra caution should be taken.
Choosing the 50% RGMB model means that the computer only applies HALF of the penalty to subsequent dives, giving you slightly longer bottom times, should happen to do something naughty (see above). Please note that in 50% RGMB mode the diver alert symbol stays on all the time as it is considered less conservative.
So there. Using the Attenuated RGBM gives you shorter surface intervals and longer bottom times on repeated dives. Why they don't put this in the manual, I don't know, but here it is. "
SO...has anyone actually dove with this RGMB model? I am curious as to how it affected the dive calculations.
