Dive Table Question

[cranstonjdc]

I am a padi certified diver reviewing how to read my tables. I stumbled upon a NAUI table that seemed easier to read so I looked at that along with my padi table. When I did a sample problem I got a different answers on each table.

Sample Dive:

1st dive: 60 Ft for 35 Min.
1/2 Hr surface interval.
2nd dive:50ft ? Min.

For the NAUI table I got 24min.
For the PADI I got 49.

As you can see this a big difference and these are the numbers the tutorial gives not just numbers I came up with myself. I am not sure if I am doing something wrong or if it is a mistake on the website tutorial I am using. The website is: Scuba Diver Info - Dive Tables Explained

Thanks For Any Help,
Jon C

 

[Thalassamania]

They are two different tables, based on two different models. The NAUI table is a more conservative version of the U.S. Navy table, the PADI is a less conservative model that was developed by DSAT. They will not yield the same answers.

 

[Mr Carcharodon]

Here's what I get:

NAUI (1990): 24
Buhlmann: 34
Huggins: 35
DCEIM (1983): 38
US Navy (1984): 44
PADI/DSAT: 49
NOAA: 53

BSAC (1988): ???
NAUI (2001): ???

It’s not like it is an exact science. Part of what is going on in tables is you get round off errors due to the way the groups are binned. That can be a pretty dramatic effect for shallow dives.

It does rather beg the question for those who always want to dive the most conservative plan why the reckless fools who are diving NOAA or DSAT tables and blowing off 30 minutes of deco are not getting bent all the time.

 

[NC Wreck Diver]

I know that the NAUI table is more conservative. I was trained NAUI a long time ago, and they really tightened up the models.

I dive with a PADI shop now, and I watch them teach students the tables. The thing I can't understand is that you need to flip the PADI table for repetitive calculations, where the NAUI table is all on one side. I like the single side better, so mistakes are less likely. Even my NAUI EAN32 & EAN36 Nitrox tables are single sided.

Computers...........what a joy! I still carry my Nitrox tables on a dive in case the computers fail.

Safe diving to you.

 

[ronbeau]

I know that the NAUI table is more conservative. I was trained NAUI a long time ago, and they really tightened up the models.

I dive with a PADI shop now, and I watch them teach students the tables. The thing I can't understand is that you need to flip the PADI table for repetitive calculations, where the NAUI table is all on one side. I like the single side better, so mistakes are less likely. Even my NAUI EAN32 & EAN36 Nitrox tables are single sided.

Computers...........what a joy! I still carry my Nitrox tables on a dive in case the computers fail.

Safe diving to you.

NAUI has now switched to using the RGBM table which are even simpler than the previous NAUI tables that were used when I got certified in 2004.

 

[Thalassamania]

I know that the NAUI table is more conservative. I was trained NAUI a long time ago, and they really tightened up the models.

I dive with a PADI shop now, and I watch them teach students the tables. The thing I can't understand is that you need to flip the PADI table for repetitive calculations, where the NAUI table is all on one side. I like the single side better, so mistakes are less likely. Even my NAUI EAN32 & EAN36 Nitrox tables are single sided.

Computers...........what a joy! I still carry my Nitrox tables on a dive in case the computers fail.

Safe diving to you.

NAUI did not "really tightened up the models," first they just stepped back one notch on the standard U.S. Navy Tables, then they moved to a RGBM algorithm.

Here's what I get:

NAUI (1990): 24
Buhlmann: 34
Huggins: 35
DCEIM (1983): 38
US Navy (1984): 44
PADI/DSAT: 49
NOAA: 53

BSAC (1988): ???
NAUI (2001): ???

It’s not like it is an exact science. Part of what is going on in tables is you get round off errors due to the way the groups are binned. That can be a pretty dramatic effect for shallow dives.

It does rather beg the question for those who always want to dive the most conservative plan why the reckless fools who are diving NOAA or DSAT tables and blowing off 30 minutes of deco are not getting bent all the time.

NOAA is U.S. Navy, so I suggest that it is less a matter of being reckless than the others being bizarrely and needlessly conservative. As to the DSAT model, that falls back on a 6 hr. maximum half time and is supposed to better model what most recreational divers do. It has a rather good record, so once again I suggest that it is less a matter of being reckless than the others being bizarrely and needlessly conservative.

 

[Garrobo]

Get a computer.

 

[cloudflint]

Ya want bizarrely and needlessly conservative? I get 11 minutes for the second dive on the RNPL tables Its interesting comparing lots of tables and seeing the results, ive found that there are some profiles which I can do on the RNPL tables that go right off the end of the buhlman tables but at the same time some profiles i can do on the buhlmann tables that go right off the end of the RNPL tables.

 

[Straegen]

I do like the NAUI format much better than PADI as well. I rely on the computer to do the math in my underwater relationship. I carry two just in case my primary computer friend is having a bad day.

 

[DiveNav]

.....Computers...........what a joy! ......

I agree