Deep Stops Recreational Divers

[markmud]

None. Recreational diving is "no stop diving".

Hi Cuzz,

I agree on both counts.

During OW a fellow student and I grilled the instructor. He claimed (along with PADI) that we were learning "No Decompression Limit" diving. The book and the instructor taught us that we could not ascend faster than 30 fpm from 60 fsw because of off-gassing issues. My fellow student and I suffered a BS meter two-block anomaly.

After we were minted OW certified, the instructor pulled both of us aside and explained the politics/marketing for "NDL" curriculum. We then, simultaneously, finished his statement by blurting out: And you have to teach the curriculum or you lose indemnification and agency protections. He smiled.

All scuba dives are decompression dives.

"No stop" is a much better term than NDL, IMHO.

No deep stops for me. Just a cautiously slow ascent; especially in the last 30 feet.

dive on,
m

 

[Eric Sedletzky]

Hi Cuzz,

I agree on both counts.

During OW a fellow student and I grilled the instructor. He claimed (along with PADI) that we were learning "No Decompression Limit" diving. The book and the instructor taught us that we could not ascend faster than 30 fpm from 60 fsw because of off-gassing issues. My fellow student and I suffered a BS meter two-block anomaly.

After we were minted OW certified, the instructor pulled both of us aside and explained the politics/marketing for "NDL" curriculum. We then, simultaneously, finished his statement by blurting out: And you have to teach the curriculum or you lose indemnification and agency protections. He smiled.

All scuba dives are decompression dives.

"No stop" is a much better term than NDL, IMHO.

No deep stops for me. Just a cautiously slow ascent; especially in the last 30 feet.

dive on,
m

Let’s not get too caught up in literal terminology like “all dives are decompression dives”. Yes true...theoretically, but the ongassing is below the level of requiring deliberate decompression stops. If I overstay the time and end up in deco then theoretically/technically it is no longer considered a recreational dive.
This whole thread is kind of an oxymoron because there aren’t any decompression stops or mandatory stops, deep or otherwise in recreational diving, there is only a suggested stop at 15’, and that’s not deep.

 

[boulderjohn]

Deep stops never were part of any training that I’m aware of in standard recreational NDL diving.

NAUI has recommended deep stops for about a decade now. Both GUE in UTD are essentially employing deep stops through their Min Deco system.

 

[Eric Sedletzky]

NAUI has recommended deep stops for about a decade now. Both GUE in UTD are essentially employing deep stops through their Min Deco system.

How deep is deep according to NAUI? How are they implementing that on recreational profiles? Depths/times? please.
I don’t know any shops teaching NAUI so I have no idea about that, It has become fringe, at least in my area.
I was unaware that GUE and UTD were teaching ground level basic OW training. Again, very fringe.
You mentioned “mini deco”, are they teaching this in their basic OW classes?

 

[markmud]

Yes true...theoretically

Hi Eric,

...theoretically..? No, I believe it is a theorem. We know that under increased pressure we on-gas and during ascent we off-gas because we are, actually, decompressing. Whether tech diving or within recreational limits.

The only arguments we do have on this theorem are about the rates of on-gassing and off-gassing in the various tissues and the huge number of variables that affect both.

We may be decompressing at a rate with small gradients that doesn't cause chronic bubble formation during so-called NDL dives; however, we are, in fact, decompressing.

Theoretically, tech diving does not require decompression stops. Control your ascent rate to the point that the gradients are manageable and you shouldn't get bent.

Difficult to do, I am told, but completely within theory.

I agree with this term: No Staged Decompression Limits (NSDL).

And yes, I have been accused of being too literal before. Words mean things.

To iterate: Why do a deep stop for NSDL diving when one can ascend slowly instead!

cheers,
markm

 

[scubadada]

Some of my computers like to add an option stop of a minute or two at depth. Maybe you should add “following my computer” as an option.

That can be turned off, correct?

 

[happy-diver]

if only to correctly define the terminology

the five Waypoints and Simple Ascent Behavior

and how to completely understand tech in two pages

 

[barth]

NAUI has recommended deep stops for about a decade now. Both GUE in UTD are essentially employing deep stops through their Min Deco system.

I did fundamentals in 2008. I didn’t learn minimum deco. I was told to use my dive computer or padi table to do my diveplanning. (Actually I should use the same method for planning as before my fundamentals, I didn’t learn a new method for planning.)

Stops were starting at half of my depth. For a 100 feet / 30 meter dive the first stop would be at 50 feet / 30 meter. There is 30 seconds for the stop and 30 seconds to go to the next stop.(50,40,30,20,10 feet / 15,11,9,6,3 meter)

I don’t like the 15 meter stop and for a simple rec dive I would also like to skip the 12 meter stop. But most of the gue buddy’s still want to do the 15 and 12 meter stop. At 15 meter with ean32 it doesn’t matter even if we I do a 5 minutes stop there is no effect for my ndl. But for me it also doesn’t make sense and it do have impact for my minimum gas.

Minimum deco I did learn from gue buddy’s before I did fundamentals. When we did a 50 minutes dive at 25 meter avg depth, max depth 30 meter. They did even stops at 21,18,15,12,9,6 and 3 meter. I don’t think they still do the 21 and 18 meter stops. I don’t know why they want to do the 21 and 18 meter stop. I think because they learnt 3/4 of the max depth for the first stop for a tech dive. But tech has been changed. I did my tech 1 in 2016 and in 2018 things were different. I’m sure they have also changed things for tech between 2008 and 2016.

 

[MargaritaMike]

Rec diving means no planned stops. So, if you blow your no deco stop plan, you start your ascent slowly and will probably clear your deco requirement on the way up. If you are really stooopid and have more deco than you can clear by slow ascent, I hope you've got enough gas to do what your computer tells you.
In any case, I think you need to get higher sooner (but not too fast), so no deep stops.
Just my $.02
Cheers -

 

[KenGordon]

That can be turned off, correct?

No, but it can be ignored.