Tables question (PADI tables) could apply to all i guess

[GDI]

What DAN article/study are you referencing? I'd like to read it and can't find it anywhere on the DAN site.

Thanks,

Jackie

It is from a few years ago and was related to their study with divers using computers and the like. I have a book buried around here somewhere I'll see if I can find it. I also have a video that mentions some of this information that was made for Duke University and of course had some advertisement for DAN in it. The Video is called Return to the Sea or something like that

 

[Hoyden]

It is from a few years ago and was related to their study with divers using computers and the like. I have a book buried around here somewhere I'll see if I can find it. I also have a video that mentions some of this information that was made for Duke University and of course had some advertisement for DAN in it. The Video is called Return to the Sea or something like that

Thanks - that gives me a better start to my search.

Jackie

 

[caseybird]

This is where computers confuse the issue, it's nice to plan the dive and enter it into the conputer. Then you can follow the profile you set by the tables.

Do any computers work this way? Where you enter a plan, and the computer guides your dive. This would be a sort of electronic slate. How would it handles departures from the plan?
Interesting device.

 

[Marek K]

But back to N@rco$i$'s (oh, that looks weird) original question...

I think the reason that the (PADI and SSI, anyway) procedures are that "bottom time" starts when your descent starts, and ends when your direct ascent starts, is that it doesn't require beginning students to have to calculate ascent rates in order to figure out when they have to start their ascents.

Otherwise, it would be like the silly guidance to "be back on the boat with 500 psi."

--Marek

 

[Rick Murchison]

Uncle Pug posted the old 120 rule awhile back,

If you want to ue such a rule, the truncated "Doppler Limits" table makes it a 110 rule.
Rick

 

[Ber Rabbit]

NAUI says it's from your descent until your head breaks the surface, the safety stop does not have to be included in the NDL time though.

From the OW book: "Actual Dive Time (ADT). This is the elapsed time from the moment you begin your descent from the surface until the time you return to the surface."

A friend and I were comparing SSI and NAUI tables and found the only difference was one stopped time at the safety stop and the other stopped time at the surface.
Ber :lilbunny:

 

[mhl354]

Diving with a good ,dependable computer and/or two will take the guess work out of the equation for you

 

[Marek K]

A friend and I were comparing SSI and NAUI tables and found the only difference was one stopped time at the safety stop and the other stopped time at the surface.
Ber :lilbunny:

Hey, I'm not sure that's correct. The PADI and SSI wording is something like, bottom time ends with the start of a diver's direct ascent to the surface. Which always meant (to me, anyway) that the safety stop wasn't factored in at all. In other words, assuming a square profile, it's when you leave the bottom to ascend.

The word "direct" means that you're not doing in effect a multi-level dive.

That was definitely the case when I was first PADI-certified in 1985; no such thing as safety stops then.

Otherwise, it would be like (from what you're saying) the NAUI way... you'd have to calculate ascent time in advance, either to your safety stop or to the surface. Not a bad idea, but I don't think that's what PADI and SSI had in mind for beginner divers.

--Marek

 

[Ber Rabbit]

I'm doing it from memory but I do remember discussing the point that there was only a 3 minute difference in the SSI and NAUI tables. I've got a heck of a head cold and cannot think clearly at the moment but I believe NAUI had 3 minutes more NDL time than SSI because NAUJI was assuming you would count the safety stop in your actual dive time and SSI wasn't. If you take the wording of both agencies and compare the tables with that in mind the two are the same, take a look at both tables and you can see for yourself. I've never worked with PADI tables.
Ber :lilbunny:

 

[Ber Rabbit]

I found an SSI table.
Depth NAUI NDL SSI NDL
40 130 130
50 80 70
60 55 50
70 45 40
80 35 30
90 25 25
100 22 20
110 15 15
120 12 10
130 8 5

OK, not exactly 3 minutes (can't think when I'm sick) but NAUI isn't giving you more dive time than SSI, they just expect you to stop your clock in a different place. I need to be in bed
Ber :lilbunny: