Does anyone who understands the Suunto algorithm know if this is a valid statement?

[lamont]

As have I but...

Bingo! That was my point.

Regardless, I'm not making bulhmann calculations on the fly on a dive.

Suunto RGBM isn't real RGBM though, its still ZHL-16b with some fudge factors derived to match the output of RGBM. I believe those are known. The full RGBM algorithm, though, is not published.

---------- Post Merged at 05:21 PM ---------- Previous Post was at 05:07 PM ----------

I get the feeling you think we're piling on you, and we aren't. I know at least Lamont and I do technical dives. I'm not allergic to deco. But I also know how to do the gas planning for it, and I also know how much risk I'm willing to take while diving a completely non-redundant equipment setup. When I think I'd like to incur some deco, I stack the odds that I'll be able to complete it safely by establishing some personal redundancy, and by diving with buddies who gas plan and also have redundancy. That way, the dives are smooth and easy and stress-free.

And there was a time when I was diving aggressively to and slightly over the NDLs, before I was deco certified, but in that case I was well down the path of training and was diving redundantly had done many dozens of s-drills, had decent enough buddy skills, etc.

If I would have had 5 minutes of mandatory BG deco and incurred 5 minutes more then I would have been able to execute that well enough.

But the general OW recreational diver doesn't have the skillset to do that.

And weither or not its a good idea without an actual deco cert is like debating driving 8 mph over the speed limit, which is illegal, even if you often don't get a ticket, and adds more kinetic energy to any crash and reduces your response times. The difference in my certification agency, at the time, between the lowest levels of certification and the first tech level was zero minutes of deco vs. 30 minutes of mandatory accelerated deco (== 60 minutes of mandatory BG deco). That step function in the certs doesn't really match the continuous variation in skill and risk involved in learning and doing the dives... So...

But if we're talking an "Advanced" OW single tank diver with their Deep/Rescue and Master diver certs... Stay out of deco, ascend when you hit it.

 

[gasgirl]

But if we're talking an "Advanced" OW single tank diver with their Deep/Rescue and Master diver certs... Stay out of deco, ascend when you hit it.

Cool. I got the message loud and clear. Thanks, lamont.

If I may be so bold, I would like to ask another opinion from you and the SB community.

BIG DISCLAIMER: I have been reading and trying to assimilate new data on decompression theory without any actual real deco training so please go easy on me if I have not correctly understood how this newfound information applies to my recreational diving practice.

An article titled "Ascending From a Dive" by Brian Morris posted on diverssupport.com makes the following suggestions:

- limit ascent rates to 30 ft/min deeper than 60 ft and 20 ft/min when less than 60 ft
- do the first deep safety stop at 1/2 MOD for 2 min
- ascend and do mini-stops of 1 min every 10 ft until 20 ft
- do a 2 min stop at 20 ft
- do a 3 min stop at 15 ft

This would suggest to me that I should change my current diving ascent rate of 30 ft/min and doing a 3 min stop at 15 ft only.

Can any of the technical divers who actually do have deco training have a look at this article and verify that this information is up to date and accurate?

Here is the link to the article: http://www.diverssupport.com/ascending.htm

Thanks again!

 

[JeffW]

Not the question you asked, but something you might want to know. I've owned a Cobra for 10 years and 300 dives and I don't believe that the issue I'm going to describe has ever affected me.

Based on information in a scubaboard post entitled "Suunto Vyper **BUG** in CNS O2 computation". I wrote this summary of the issue for myself to keep with my Suunto Cobra manual (the description I wrote refers to the cobra interfaces)...

Suunto will penalize you for exceeding the MOD very severely. For example, set the computer to 32% O2 and the PO2 warning to 1.4. Then do a SIMDIVE simulation going to 107 ft (the MOD at 1.4 po2). You will notice that the OLF bar graph on the left is rising fast to the yellow level by 15 minutes into the dive. This is the case even when the DSAT tables show you have a maximum of 150 minutes at this depth. The computer accumulates OLF time at 10 times the table rate. If you do the SIMDIVE at 105 ft it doesn't apply this extreme penalty. This can cause the computer to lock you out if you use up all your 24 hour oxygen exposure (aka CNS clock or aka OLF on the suunto). The bottom line... stay above the 1.4 MOD depth by a couple of feet. Setting the PO2 warning to a higher value like 1.5 or 1.6 will have no affect on this behavior.