Difference between MB levels and Gradient Factors

[tursiops]

In post #125, you quote me asking you for research: "Could you post the studies that show this is beneficial? I have done a lot of research on this topic, and I seem to have missed" Your response does not cite any of those studies. You ignore the question you quoted.

Then you challenged me to cite research, and I did that in the post above this. So here is the question again: "Could you post the studies that show this is beneficial? I have done a lot of research on this topic, and I seem to have missed it."

Why are we letting this guy troll us?

 

[scubadada]

Hi @ChrisDee

You are a fan of the G2, Scubapro is migrating away from Buhlmann ZH-L8 or 16 ADT MB to Buhlmann ZH-L16 with GF.

Many computers enter into violation gauge mode when you violate a deco stop

SurfGF is easy, the GF with immediate surfacing. It will always be less after a normal ascent rate.

Nearly every computer has a variable ascent rate.

A shorter time at depth and a longer ascent, especially shallow, should be safer, less exposure. Of course, all commercially available decompression algorithms are "safe"

What are the specific reasons that the G2 is superior to all other dive computers?

 

[boulderjohn]

ig issue is with GF and Sur GF is yo have to do mental gymnastics to understand what computer is trying to tell you. With G2 yo set it, you set it according to your plan. It does what a computer is supposed to do, rather than trying to figure things out real time. BTW, many users of SurGF and GF style have reported that they find spend most time staring at coputer tyring to figure it out. This is not a positive.

Also others set GF high / low, but this isn't what shows up on screen and you people continue to promote this confusion as a positve? Seems all you want to do is bash something you know nothing about.

Here is a link to Hal Watts' Gradient Factors for Dummies. It might help, but for NDL diving, it is more than you need.

For NDL diving, you don't need to know any of that. All you need to care about is the second gradient factor, and here is all you need to know for that.

Think of the GF high as telling you how close you want to come to 100% of the normal Buhlmann limits for surfacing. A GF high of 90 would be considered aggressive, and a GF high of 70 would be considered conservative. The lower you make that setting, the shorter your no decompression limits. The SurfGf tells you how close you would be to the surfacing limits if at that time you could go to the surface instantly.​

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Evidently that requires too much mental gymnastics for you and the people with whom you dive. In that case, you definitely don't want that kind of information screwing with your mind and confusing you when you dive, and you absolutely should not be making any decisions on your own.

 

[scubadada]

On your G2 you must set you MB level, respiratory rate sensitivity, heart rate response, body temperature response. Do any of these variables have publicly available data to support the settings?

 

[tursiops]

On your G2 you must set you MB level, respiratory rate sensitivity, heart rate response, body temperature response. Do any of these variables have publicly available data to support the settings?

LOL. Rhetorical question? Be interesting to see his response.

 

[dmaziuk]

In all fairness, does anybody have any data to support the assumption that GF70 is "safer" than GF95 and by how much?

The common sense says it should be. The same source says faster heart rate should lead to faster gas exchange. Potayto, potahto.

 

[scubadada]

You can plug in your time and depth for air or 32% into the SAUL recreational dive planner and calculate your risk of DCS.

SAUL Recreational Dive Planner | Modern Decompression

Increased exposure is increased risk, as you would assume.

So, a GF high of 70 is "safer" than a GF high of 95, duh!

 

[dmaziuk]

Yes, and how many goats did he explode while verifying his algorithm?

 

[scubadada]

Yes, and how many goats did he explode while verifying his algorithm?

Read the background. This is a probabilistic algorithm based on extensive available databases.

 

[dmaziuk]

Read the background. This is a probabilistic algorithm based on extensive available databases.

I have, that's how I know the abstract of "the most relevant to SAUL" article ends with "If empirically verified, this may have important implications for diving practice". AFAICT his work is twice-removed from the primary data -- not that it makes it any less good, but it does provide some perspective on its practical applicability.

(And I'm yet to read DOI:10.1152/jappl.1984.57.3.815 and see if that explains what "probabilistic" actually means in this particular context.)