Your Gradient Factors?

[PfcAJ]

Take one of my typical no-stop dives: 25 min @25m, 25 min @15m. According to every table, I'd be way into deco. According to multilevel planning or any deco software, I'd be no-stop. My average depth is 20m, my bottom time is 50 min. By average depth and tables, I'd be in deco. But I'm not, neither by deco software nor by reality.

seems kosher according to my NAUI air table that I have sittin here.

60ft for 55mins is their limit.

 

[tursiops]

I just ran your example in iDeco with Bühlmann.

still a no-deco dive.

And do you get 15 minutes difference in the dive time?

 

[CAPTAIN SINBAD]

Daym. Do you DIR guys ever enjoy a dive for its own and stop to smell the flowers, or do you exclusively focus on the technicalities? Me, there's no way I'd enjoy the dive and stop to smell the flowers if I were to follow that prescription. My entire mental bandwidth would've been occupied. Particularly at 30+m.

Well you will just wear an electronic bottom timer that shows you average depth. You will know your bottom time by memory in relation to that average depth that the bottom timer is showing. It is actually simpler than a computer. You save 15 seconds of switching it from AIR to NITROX mode Big deal right?

 

[Storker]

seems kosher according to my NAUI air table that I have sittin here.

My PADI RDP says that max no-stop time at 20m is 45 min.
As does the Norwegian National Table (NDBT). 50 min @ 20m requires 5 min deco @3m.

So 50 min @20m no-stop is 1:2 halal:haram by available data ATM

 

[Storker]

60ft for 55mins is their limit.

60' is ~18m. For 20m, you have to use 70'

 

[tursiops]

60' is ~18m. For 20m, you have to use 70'

Hey, if you are averaging in your head and using variable definitions anyway, what difference does 2m make?

 

[PfcAJ]

Hey, if you are averaging in your head and using variable definitions anyway, what difference does 2m make?

It doesn’t

 

[tursiops]

@Storker I think the point is, once you've decided to discard the tables or use them incorrectly, then guesses and speculation and assertions and kool-aid and hope are plenty good enough. No thanks.

 

[Storker]

what difference does 2m make?

11 min no-stop time according to the metric PADI RDL. Or 19 if you exceed the 20m limit ever so slightly.
15 min no-stop time according to our national table (it doesn't have times for 20m, only for 21m).

For a max no-stop bottom time of 56-60 min at the lower depth (18m), depending on which table you choose to follow. In my world, 11/56 or 15/60 is not insignificant.

 

[tursiops]

It doesn’t

11 min no-stop time according to the metric PADI RDL. Or 19 if you exceed the 20m limit ever so slightly.
15 min no-stop time according to our national table (it doesn't have times for 20m, only for 21m).

For a max no-stop bottom time of 56-60 min at the lower depth (18m), depending on which table you choose to follow. In my world, 11/56 or 15/60 is not insignificant.

So the "average answer" is presumably half-way between zero difference and 15 minutes, so 7.5 minutes, exactly. Jeez.