Where Is Your GF?

[Michael Guerrero]

In all the discussion, let's not forget that the 100/100 profile did not produce a DCS probability of 100%. It was something low, like below 5%, and I want to say around 2-ish, in fit U.S. Navy divers, the more susceptible of whom had likely already self-eliminated. It is therefore reasonable that you could dive 100/100 dives and never get DCS. The evaluation of the NEDU study showed not only uncharacteristic ascent profiles, but also highly provocative conditions, and still the DCS incidence was in low ranges.

We are a long way from identifying optimal, but well within the safe envelope for most diving.

 

[scubadada]

Interesting that this thread has more than 4600 views, 91 posts, and only 85 votes in the poll, perhaps because the choices were not very good

 

[PfcAJ]

Interesting that this thread has more than 4600 views, 91 posts, and only 85 votes in the poll, perhaps because the choices were not very good

Also perhaps that many divers don’t have a clue as to what their GFs are.

 

[Joneill]

Also perhaps that many divers don’t have a clue as to what their GFs are.

None of the standard Shearwater presets for Low, Medium or High being choices is a reason for a number of us too, I suspect!

 

[KenGordon]

Also perhaps that many divers don’t have a clue as to what their GFs are up to.

Fixed that for you. Mine’s not there. But I agree, mostly people don’t use GF and plenty who do will be on the default. And of those that do know the number how many understand what it means. And of those, how man6 have a reasonable reason for choosing the numbers they chose?

 

[Remy B.]

Interesting that this thread has more than 4600 views, 91 posts, and only 85 votes in the poll, perhaps because the choices were not very good

Perhaps is because not al GF factors are posted, world forum = a lot of GF preferences

If you had put 45/75 then that will be my vote

 

[Jay]

Interesting that this thread has more than 4600 views, 91 posts, and only 85 votes in the poll, perhaps because the choices were not very good

Perhaps because there’s too many variables in a diver’s decision matrix:
Rec divers diving Rec
Tech divers diving Tec and/or Rec
Multi day multi dives LOB type
Warm water
Easy dive
Etc

My diving is all tropical/warm water Rec, typically non strenuous. I’m happy at/between DSAT and PZ+ on 1-2 dives/day and 2+ or multi day’s of diving respectively.

To the best of the info out there this translates to GFs of xx/90-95. (GF lo isn’t taken into consideration on my Teric)

I typically don’t run either lower than 5mins and prefer 5 min SS with super slow ascents*

*Having conservatism built in outside GFs is just the way I like to do it in Rec and works nicely when DM asks to ‘let me know when you’re down to Xmin NDL’. I’m guesstimating this would effectively mean a GF hi of the above range less 5.

I think, for Rec, a interesting question would be is what’s your typical surfacing GF. (I’m assuming for Tec, given it’s the target) it is ?always? GF hi.

 

[stuartv]

For Tech, it's NORMALLY GF Hi OR LESS.

 

[Trace Malinowski]

Ratio deco, 20/85, or VPM+2. What can I say? I'm a Cancer. We hate change.

 

[Michael Guerrero]

I chose the numbers, and put "approximate" in the initial post, purposefully. For folks who don't want to play because it's not their exact number, or because they bounce around...well, I can't make them. But there are reasonable answers (e.g., most comfortable, most common, etc.) that would give an indication of where people value their deco time in their ascent profile (i.e., deep, shallow, both).

Interestingly (to me anyway), more than 50% of folks are diving a GF lo of approximately 50 or higher. I suspect that would be a different story even 5 years ago.